Journal of Arthroplasty

Journal of Arthroplasty

Letter to the Editor on “Advanced Age Is Not a Barrier to Total Knee Arthroplasty: A Detailed Analysis of Outcomes and Complications in an Elderly Cohort Compared With Average Age Total Knee Arthroplasty Patients”

01-10-2019 – Raju Vaishya, Abhishek Vaish

Letter

Response to Letter to the Editor on “Reliability and Validity of the Vancouver Classification in Periprosthetic Fractures Around Cementless Femoral Stems”

22-09-2019 – Shanjean Lee, Ryland Kagan, Yee-Cheen Doung, Lian Wang

Letter

Letter to the Editor on “Reliability and Validity of the Vancouver Classification in Periprosthetic Fractures Around Cementless Femoral Stems”

14-09-2019 – Siamak Sabour

Letter

Patellar Resurfacing in Primary Total Knee Arthroplasty: Axa0Meta-Analysis of Randomized Controlled Trials

21-08-2019 – Aaron J. Teel, John G. Esposito, Brent A. Lanting, James L. Howard, Emil H. Schemitsch

Journal Article

Background

The management of the patella during total knee arthroplasty (TKA) remains controversial. The aim of this study is to evaluate the evidence regarding the use of patellar resurfacing in TKA.

Methods

A meta-analysis of randomized controlled trials (RCTs) was performed to compare outcomes between knees receiving patellar resurfacing vs those not receiving resurfacing during primary TKA. Outcomes of interest were the Knee Society Scores, reoperation rates, anterior knee pain, patient satisfaction, Oxford Knee Score, Knee Injury and Osteoarthritis Outcome Score subscores, and range of motion.

Results

Twenty RCTs met all eligibility criteria and were included in the analysis. There were statistically significant differences favoring the resurfaced group in the knee component and functional component of Knee Society Scores that were not clinically significant. There was an increased risk of reoperation among knees that did not receive resurfacing with number needed to treat to prevent one case of reoperation of 25 knees (for reoperation for any reason) and 33 knees (for reoperation for anterior knee pain). There were no statistically significant differences in any other outcomes.

Conclusion

The only clear relationship is that knees that do not receive patellar resurfacing are more likely to receive reoperation, most often for secondary resurfacing. However, the disease burden of differing complication profiles associated with resurfacing and nonresurfacing groups remains unclear. Continuing to collect data from large, well-designed RCTs would be beneficial in guiding management of the patella during TKA.

Comparison of Fixed-Bearing and Mobile-Bearing Unicompartmental Knee Arthroplasty: A Systematic Review and Meta-Analysis

03-09-2019 – ZhenWu Cao, CaiLi Niu, ChunZhu Gong, Yong Sun, JunHui Xie, YueLi Song

Journal Article, Review

Background

Prior studies have compared fixed-bearing unicompartmental knee arthroplasty (FB-UKA) with mobile-bearing UKA (MB-UKA), suggesting that both procedures have good clinical outcomes. However, which treatment is more beneficial for patients is controversial. The purpose of our study is to evaluate the postoperative outcomes, including the revision rate, complications, functional results, range of motion, and femoral-tibial angle, between the 2 procedures.

Methods

We searched the MEDLINE, EMBASE, Cochrane Library, and Web of Science databases starting from August 2017 to May 2018. The publication date of articles was not restricted. Before we submit our contribution, we have re-searched it again. Articles that directly compared the postoperative outcomes of the 2 prosthesis type were included.

Results

A total of 15 comparative studies were included in our meta-analysis. The pooled data indicated no differences between the 2 operation modes in terms of revision rates, complications, and knee function, but earlier failure occurred more frequently with the MB design.

Conclusion

Both the arthroplasty types provided satisfactory clinical results for patients with classic indications. However, MB-UKA tended to fail in early postoperative years whereas fixed-bearing UKA in later postoperative years. Therefore treatment options should be carefully considered for each patient, and surgeons should still use their personal experience when deciding between these options.

Influence of Hip Geometry Reconstruction on Frontal Plane Hip and Knee Joint Moments During Walking Following Primary Total Hip Replacement

21-08-2019 – Felix Stief, Stefan van Drongelen, Marco Brenneis, Timur Tarhan, Benjamin Fey, Andrea Meurer

Journal Article

Background

Following total hip replacement (THR), hip geometry reconstruction parameters such as the femoral offset (FO) correlate with hip stability and wear. The purpose of this study is to determine the relationship between hip geometry parameters and knee and hip joint loading during walking.

Methods

Forty-one patients were examined before and a minimum of 1 year after primary THR. Pearson correlation coefficient (r) was performed to identify relationships between radiographic parameters and gait data. In addition, we divided patients into 2 groups according to the restoration of the FO (within ±5 mm vs more than 5 mm increment).

Results

The FO and global offset (GO) showed a positive correlation with the first (r = 0.469, P = .002; r = 0.542, P < .001) and second (r = 0.365, P = .019; r = 0.484, P = .001) knee adduction moment (KAM). The neck-shaft angle revealed a negative correlation with the first hip adduction moment (r = −0.375, P = .047). The reconstruction of FO with an increment of more than 5 mm was associated with a significant higher first KAM (+16%, P = .045) compared to the restored group.

Conclusion

Our findings suggest that abnormal hip and knee joint loading during walking after THR have a biomechanical background originating from hip geometry reconstruction. Patients with a high FO/GO were more likely to have an increased KAM during walking or vice versa. Surgeons need to be aware that an accurate control of FO, GO, and neck-shaft angle restoration in THR has an impact on hip and knee joint loading that may influence degenerative changes of the knee and higher wear of the artificial hip joint, respectively.

Bilateral High Hip Center Provides Gait Parameters Similar to Anatomical Reconstruction: A Gait Analysis Study in Hip Replacement Patients With Bilateral Developmental Dysplasia

30-07-2019 – Bedri Karaismailoglu, Gokhan Kaynak, Ata Can, Mahmut Kursat Ozsahin, Fahri Erdogan

Journal Article

Background

Total hip arthroplasty in severe dysplasia is challenging due to diminished periacetabular bone stock and the highly placed femoral head. Although anatomical reconstruction of the hip, with required interventions such as subtrochanteric osteotomy and graft usage, is the main aim of the procedure, good long-term clinical outcomes of the high hip center technique have also been reported. Information regarding the effect of hip center placement on gait characteristics is limited; therefore, the aim of this study is to analyze the differences in gait parameters between the high hip center technique and anatomical reconstruction of the hip.

Methods

Twenty patients (40 hips) with bilateral Crowe type III-IV developmental dysplasia of the hip who underwent bilateral total hip arthroplasty and completed at least 2 years of follow-up were included. Group 1 comprised 10 patients (20 hips) who underwent anatomical hip center reconstruction, while group 2 comprised 10 patients (20 hips) who underwent high hip center reconstruction. The gait characteristics of patients were examined through markers placed in certain anatomical regions, the cameras placed around, and the force plates embedded in the walking platform.

Results

There was no significant difference in the gait characteristics according to the location of the hip rotation center. The mean temporospatial, kinematic, and kinetic values were similar between the groups. The most prominent difference was in the peak dynamic hip extension, which was lower in group 2 (−9.71° ± 7.46°) compared to group 1 (−6.80° ± 11.44°), although it was not statistically significant (P = .09).

Conclusion

The bilateral high hip center technique can provide similar gait characteristics as anatomical reconstruction and may be preferred in particularly difficult cases based on the surgeon’s decision.

Zirconia Phase Transformation in Zirconia-Toughened Alumina Ceramic Femoral Heads: An Implant Retrieval Analysis

14-08-2019 – Thu M. Nguyen, Lydia Weitzler, Christina I. Esposito, Alessandro A. Porporati, Douglas E. Padgett, Timothy M. Wright

Journal Article

Background

Zirconia-toughened alumina ceramic was introduced as a femoral head material for total hip arthroplasty. The material combines the stability of alumina with the toughness of zirconia. Despite inherent benefits for bearing surfaces, concern exists in the medical field that phase transformation of the zirconia grains could worsen wear resistance and lower the strength of the head. We examined these concerns in retrieved and artificially aged ceramic heads.

Methods

Twenty-eight ceramic composite heads retrieved at revision surgery were combined with 5 pristine heads (as negative controls for phase transformation) and 5 artificially aged pristine heads (as positive controls). The extent of zirconia phase transformation at the bearing surfaces was examined through confocal Raman spectroscopy and X-ray diffraction. Burst testing was conducted on all pristine and aged heads and the 4 retrieved implants with the longest lengths of implantation.

Results

Retrieved heads had higher maximum average volume fractions of the monoclinic phase compared to pristine or aged heads. Length of implantation was not correlated to the volume fraction of the monoclinic phase. All the heads achieved a burst load far above the 46 k
N Food and Drug Administration acceptance criterion; 3 of the 4 retrieved heads had burst strengths exceeding 100k
N.

Conclusion

Our results showed that phase transformation occurs in vivo in ceramic composite femoral heads, but the amount transformed did not increase with the length of time the head had been implanted. The negligible effect upon burst strength of the retrieved and artificially aged heads is reassuring. These results support continued clinical use of this alumina-zirconia composite material as a head material.

Reasons for Revision, Oxidation, and Damage Mechanisms of Retrieved Vitamin E-Stabilized Highly Crosslinked Polyethylene in Total Knee Arthroplasty

17-08-2019 – Hannah Spece, Jaclyn T. Schachtner, Daniel W. MacDonald, Gregg R. Klein, Michael A. Mont, Gwo-Chin Lee, Steven M. Kurtz

Journal Article

Background

In order to improve oxidation resistance, antioxidants such as vitamin-E are added to polyethylene used in the bearing surfaces of orthopedic components. Currently, little is known about the efficacy of this treatment in vivo. This study therefore reports on the reasons for revision, surface damage mechanisms, and oxidation of retrieved vitamin E-stabilized highly crosslinked polyethylene (HXLPE) for total knee arthroplasty.

Methods

We examined 103 retrieved knee inserts fabricated from vitamin E (VE)-stabilized HXLPE and 67 fabricated from remelted HXLPE as a control. The implantation times were 1.2 ± 1.3 and 1.5 ± 1.3 years for the VE and control cohorts, respectively. The inserts were evaluated for 7 surface damage mechanisms using a semiquantitative scoring method and analyzed for oxidation using Fourier-transform infrared spectroscopy. Reasons for revision were also assessed using operative notes created at time of retrieval.

Results

Both groups were revised primarily for instability, infection, and loosening. Burnishing, pitting, and scratching were the most common damage mechanisms observed, with the VE cohort demonstrating less surface damage than the control. Measured oxidation for the cohort was low, with a median oxidation index of 0.09 ± .05 for the articulating surface, 0.05 ± 0.06 for the backside, 0.08 ± 0.06 for the anterior/posterior surfaces, and 0.08 ± 0.05 for the stabilizing post. As compared to the control cohort, oxidation tended to be less for the VE group at the articulating (P < .001) and backside (P = .003) surfaces, although the median differences were minimal and may not be clinically significant.

Conclusion

The results indicate positive fatigue damage resistance and oxidation resistance for the retrieved VE-stabilized total knee arthroplasty inserts.

Tibial Tubercle-Trochlear Groove Distance Influences Patellar Tilt After Total Knee Arthroplasty

28-08-2019 – Shinichiro Nakamura, Koichiro Shima, Shinichi Kuriyama, Kohei Nishitani, Hiromu Ito, Shuichi Matsuda

Journal Article

Background

Tibial tubercle-trochlear groove (TT-TG) distance is associated with a greater risk of recurrent patellar dislocation in young, active patients. However, the effect of TT-TG distance after total knee arthroplasty (TKA) has not been investigated. The purpose is to analyze the effect of TT-TG distance and component rotation on patellar tilt and patellar shift after TKA.

Methods

After TKA, axial computed tomography scans and axial radiograph were taken in 115 consecutive knees. TT-TG distance was measured between the most anterior point of the tibial tuberosity and the deepest point of the femoral component relative to a line connecting the anterior condyles. Femoral and tibial component rotation was measured relative to the femoral and tibial rotational axis, respectively. Pearson correlation coefficients were calculated.

Results

TT-TG distance had a significant correlation with patellar tilt in extension (R = 0.220, P = .018), patellar tilt in flexion (R = 0.438, P < .001), and patellar shift (R = 0.330, P < .001). Tibial component rotation had a significant correlation with patellar tilt in flexion (R = −0.251, P = .007) and patellar shift (R = −0.360, P < .001). Femoral component rotation had no significant correlations. Tibial component rotation had a significant correlation with TT-TG distance (R = −0.573, P < .001), whereas femoral component rotation had no correlation (P = .192).

Conclusion

TT-TG distance had a significant correlation with patellar tilt and patellar shift. Surgeons need to understand the factors affecting TT-TG distance and to pay attention to avoiding excessive TT-TG distance after TKA.

Prevalence of Postoperative Periprosthetic Femur Fractures Between Two Different Femoral Component Designs Used in Direct Anterior Total Hip Arthroplasty

07-08-2019 – Katherine S. Christensen, Daniel I. Wicker, Christian M. Wight, Christian P. Christensen

Journal Article

Background

Periprosthetic femur fractures are a well-documented complication following direct anterior uncemented total hip arthroplasty. The purpose of this study is to compare the prevalence of postoperative periprosthetic femur fractures between 2 different femoral component designs used in direct anterior total hip arthroplasty.

Methods

Beginning in February 2015, a single fellowship-trained adult reconstruction surgeon performed 361 consecutive direct anterior total hip replacements using a flat, single-taper, wedged femoral implant. In June 2016, that same surgeon, using the exact same surgical technique and postoperative weight-bearing protocol, began using a dual-taper, hydroxyapatite-coated implant for 789 consecutive hips. The patients were carefully monitored for 3 months after surgery to identify the frequency of periprosthetic femur fractures. A Fisher’s exact test was used to determine if the prevalence of periprosthetic femur fractures differed between the 2 implant designs.

Results

Five of 361 (1.4%) patients sustained proximal femur fractures at an average of 19.6 days postoperatively in the first group, all demonstrating a Vancouver type B2 periprosthetic fracture and requiring femoral revision. No patients (0/789, 0%) in the second cohort sustained a postoperative, periprosthetic fracture (P = .006).

Conclusion

In this comparison of 2 consecutive cohorts, the dual-taper, hydroxyapatite-coated implant had a statistically significant lower postoperative periprosthetic fracture rate than a flat, single-taper, wedged design.

Risk Factors for Intraoperative Periprosthetic Femoral Fractures During Primary Total Hip Arthroplasty. An Analysis From the National Joint Registry for England and Wales and the Isle of Man

30-07-2019 – Jonathan N. Lamb, Gulraj S. Matharu, Anthony Redmond, Andrew Judge, Robert M. West, Hemant G. Pandit

Journal Article

Background

The aim of this study is to estimate risk factors for intraoperative periprosthetic femoral fractures (IOPFF) and each anatomic subtype (calcar crack, trochanteric fracture, femoral shaft fracture) during primary total hip arthroplasty.

Methods

This retrospective cohort study included 793,823 primary total hip arthroplasties between 2004 and 2016. Multivariable regression modeling was used to estimate relative risk of patient, surgical, and implant factors for any IOPFF and for all anatomic subtypes of IOPFF. Clinically important interactions were assessed using multivariable regression.

Results

Patient factors significantly increasing the risk of fracture were female gender, American Society of Anesthesiologists grade 3 to 5, and preoperative diagnosis including avascular necrosis of the hip, previous trauma, inflammatory disease, pediatric disease, and previous infection. Overall risk of IOPFF associated with age was greatest in patients below 50 years and above 80 years. Risk of any fracture reduced with computer-guided surgery and in non–National Health Service hospitals. Nonposterior approaches increased the risk of shaft and trochanteric fracture only. Cementless implants significantly increased the risk of only calcar cracks and shaft fractures and not trochanteric fractures.

Conclusion

Fracture risk increases in patients younger than 50 and older than 80 years, females, American Society of Anesthesiologists grade 3 to 5, and indications other than primary osteoarthritis. Large cumulative reduction in IOPFF risk may occur with use of cemented implants, posterior approach, and computer-guided surgery.

Level of Evidence

Level 3b (cohort study).

Undersedation During Total Hip Arthroplasty Reduction Results in Worse Patient Outcomes

15-08-2019 – Sean P. Ryan, Thomas J. Hopkins, Samuel S. Wellman, William A. Jiranek, Michael P. Bolognesi, Thorsten M. Seyler

Journal Article

Background

Total hip arthroplasty (THA) dislocation is a common reason for presentation to the emergency department (ED) postoperatively. Prior literature has shown that propofol conscious sedation provides the fewest complications and the shortest time to reduction. However, we are aware of no prior reports exploring sedative dosing regimens. We hypothesized that “undersedated” patients would have worse outcomes compared to appropriately sedated patients based on dose.

Methods

This is a retrospective review of isolated propofol conscious sedation performed in the ED for closed reduction of THA dislocations from 2013 to 2019. Prior authors have used at least 0.5 mg/kg/dose for sedation with propofol. Therefore, to allow a 10% rounding error, a dose of less than 0.45 mg/kg/dose was considered undersedated. Demographic information was collected and outcomes including sedation time, number of doses, complications, and successful reductions were analyzed in univariable and multivariable analyses.

Results

A total of 79 THAs were included for analysis with mean age 65.5 (16.2) years and weight 84.1 (21.3) kg. Thirty-seven (46.8%) patients had undergone revision surgery and 44 (55.7%) previously had a dislocation. A total of 39 patients were undersedated. There was no significant difference in demographics or arthroplasty-specific variables between undersedated and “protocol” sedation patients. In multivariable analysis, undersedated patients had significantly longer sedation time (P = .020), more re-doses (by mean 3 doses; P < .001), and greater total dose (P = .002). These patients were also more likely to have failed ED closed reduction (10.3% vs 0.0%; P = .038). One complication of a skin tear from countertraction was observed in an undersedated patient.

Conclusion

Historically, conscious sedation for THA dislocations has been the responsibility of the emergency room clinician. In consideration of our outcomes, we advocate for a multidisciplinary team to create a sedation protocol, emphasizing the need to maintain a dosing regimen of 0.5 mg/kg/dose to improve the care of THA patients.

Valgus Subsidence of the Tibial Component Caused by Tibial Component Malpositioning in Cementless Oxford Mobile-Bearing Unicompartmental Knee Arthroplasty

06-08-2019 – Tomoyuki Kamenaga, Takafumi Hiranaka, Yuta Nakanishi, Koji Takayama, Ryosuke Kuroda, Tomoyuki Matsumoto

Journal Article

Background

Valgus subsidence (VS) of the tibial component is a rare complication of unicompartmental knee arthroplasty (UKA), and surgeons might consider revision surgery. The present study aimed to identify the factors related to VS of the tibial component after cementless Oxford mobile-bearing UKA.

Methods

The study included 120 patients who underwent Oxford mobile-bearing UKA using a cementless tibial component in our center between September 2015 and September 2016. Six showed VS of >2° after surgery. Patients were stratified into 2 groups according to the occurrence of VS of the tibial component (VS group, n = 6; no-subsidence group, n = 114). Postoperative radiographic evaluations were conducted to assess the varus/valgus alignment, rotation, and mediolateral position of the tibial and femoral components. The Oxford Knee Score (OKS) was assessed at 3, 6, and 12 months postoperatively. Positional parameters and sequential change in OKS were compared between the two groups using unpaired t-test (P < .05, statistically significant).

Results

At 3 months postoperatively, an average VS of 3.4° in the VS group was observed, with a significant decrease in OKS. VS was associated with a significantly more medial position and external rotation of the tibial component. After 3 months, VS stopped, and the OKS gradually improved without revision surgery.

Conclusions

VS might be caused by the malpositioning of the tibial component. VS of the tibial component after UKA appears to stop, with simultaneous pain relief, even without revision after 3 months postoperatively.

Partial 2-Stage Exchange for Infected Total Hip Arthroplasty: An Updated Report

30-07-2019 – David A. Crawford, Joanne B. Adams, Michael J. Morris, Keith R. Berend, Adolph V. Lombardi

Journal Article

Background

Management of an infected total hip arthroplasty (THA) is challenging. The eradication of infection as well as complications of component removal must all be considered. This study is an update on previous reports of treating periprosthetic infection of the hip with a partial 2-stage exchange with retention of the femoral component.

Methods

A retrospective review of our practice’s arthroplasty registry from 2000 to 2018 revealed 41 hips with 2-year minimum follow-up that were treated with a 2-stage partial exchange for an infected THA. All first-stage procedures allowed an articulating construct with 1 of 3 variations: cemented constrained liner (13 hips), Stage
One Hip Cement Spacer Mold (14 hips), or an antibiotic polymethylmethacrylate head molded from a bulb syringe (14 hips). Of 41 cases, 34 were culture positive, with 3 cases having methicillin-resistant Staphylococcus.

Results

Mean follow-up was 5.5 years (range, 1.5-18.5 years). The second-stage reimplantation was accomplished in 39 of the 41 hips (95%) at a mean interval of 9.2 weeks (range, 5-9 weeks). Two patients underwent repeat radical debridement with removal of all components before reimplantation for persistent clinical evidence of infection. Thirty-three of the 41 hips (81%) were infection free at most recent follow-up. The mean postoperative Harris hip score at most recent evaluation was 63.6 (range, 24-100).

Conclusion

Eradication of periprosthetic joint infections, while minimizing patient morbidity, continues to be a challenge. Partial 2-stage exchange may be considered in cases where removal of a well-fixed femoral component may result in significant bony destruction.

Primary Total Knee Arthroplasty Implants as Functional Prosthetic Spacers for Definitive Management of Periprosthetic Joint Infection: A Multicenter Study

06-08-2019 – Ahmed Siddiqi, James Nace, Nicole E. George, Eric J. Buxbaum, Alvin C. Ong, Fabio R. Orozco, Danielle Y. Ponzio, Zachary D. Post

Journal Article

Background

There are limited data on the utility of a standard primary total knee arthroplasty (TKA) femoral component with an all polyethylene tibia as a functional prosthetic spacer in place of a conventional all cement spacer for the management of periprosthetic joint infection (PJI). The aim of this multicenter study was to retrospectively review (1) ultimate treatment success; (2) reimplantation rates; (3) reoperation rates; and (4) change in knee range of motion in patients managed with functional prosthetic spacers following TKA PJI.

Methods

A retrospective review was performed for patients at 2 tertiary care centers who underwent a functional prosthetic spacer implantation as part of a functional single-stage (n = 57) or all cement spacer conventional two-stage (n = 137) revision arthroplasty protocol over a 5-year period. Outcomes including reinfection, reimplantation, and reoperation rates, success rate as defined by the Delphi criteria, and final range of motion were compared between the 2 cohorts at a minimum of 2-year follow-up.

Results

There was no significant difference in reinfection (14.0 vs 24.1%), reoperation (19.3 vs 27.7%), or success rates (78.9 vs 70.8%; P > .05 for all) between the one-stage and two-stage revision TKA cohorts. Mean final total arc of motion was also similar between the 2 groups (105.8 vs 101.8 degrees, respectively).

Conclusion

Functional prosthetic spacers offer the advantage of a single procedure with decreased overall hospitalization and improved cost-effectiveness with analogous success rates (78.9%) compared with two-stage exchange (70.8%) at mid-term follow-up. Although long-term data are required to determine its longevity and efficacy, the outcomes in this study are encouraging.

Level of Evidence

3.

Plasma Viscosity Has a Role in the Diagnosis of Prosthetic Joint Infection After Total Knee Arthroplasty

27-08-2019 – Stefan Bajada, Andrel W.H. Yoong, Patrick Hourigan, Petra C. Koopmans, Jonathan R.A. Phillips, Andrew D. Toms

Journal Article

Background

The diagnosis of prosthetic joint infection (PJI) is challenging because no single test has consistently demonstrated an adequate discriminative potential. The combination of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) with adequate thresholds is well established. This study sought to investigate the role of plasma viscosity (PV) in the diagnosis of PJI following painful total knee arthroplasty.

Methods

The medical notes, and hematological and microbiology results of 310 patients who underwent revision for a painful total knee arthroplasty were evaluated. Infection was confirmed using Musculoskeletal Infection Society criteria in 102 patients (32.9%), whereas 208 patients (67.1%) were classified as noninfected. Serum investigations including ESR, CRP, and PV were analyzed using receiver observer curves and optimal cutoff points identified.

Results

There was a strong correlation between PV and both ESR and CRP. The area under curve was 0.814 for PV and 0.812 for ESR. Statistical analysis showed noninferiority of PV as compared to ESR in diagnosing PJI. A PV value of ≥ 1.81 m
Pa.s. had the best efficiency of 82.1%. Combining a CRP ≥ 13.5 mg/L with a PV ≥ 1.81 m
Pa.s. in a serial test approach yielded the highest specificity of 97.9% and positive likelihood ratio of 22.8. Sensitivity was 47.9% and a negative likelihood ratio of 0.53.

Conclusion

PV is noninferior to ESR in diagnosing PJI. Its use is justified in clinical practice. It is cheaper, quicker, more efficient, and not influenced by hematocrit levels or medication. In this cohort, a PV value ≥ 1.81 m
Pa.s. would be an adequate cutoff to diagnose PJI in combination with CRP ≥ 13.5 mg/L.

Positive Blood Cultures Decrease the Treatment Success in Acute Hematogenous Periprosthetic Joint Infection Treated With Debridement, Antibiotics, and Implant Retention

05-08-2019 – Feng-Chih Kuo, Karan Goswami, Mitchell R. Klement, Noam Shohat, Javad Parvizi

Journal Article

Background

The influence of positive blood cultures on surgical outcome of acute hematogenous periprosthetic joint infection (PJI) treated by debridement, antibiotics, and implant retention (DAIR) remains unknown. This study evaluated the influence of positive blood cultures on the treatment success of DAIR in patients with acute hematogenous PJI.

Methods

A retrospective chart review on 49 patients with blood culture data for acute hematogenous PJI was performed from 2005 to 2016 at a single institution. All patients were treated by DAIR and had a minimum follow-up of 1 year. Treatment success was defined by the Delphi criteria. Multivariate logistic regression analysis was performed to identify variables associated with positive blood culture and treatment success. Kaplan-Meier survivorship curves and log-rank tests were used for analysis.

Results

Overall, 44.9% (22/49) of blood cultures obtained yielded positive growth. Elevated Elixhauser comorbidity index was a significant risk factor associated with positive blood (adjusted odds ratio OR, 1.65; 95% confidence interval CI, 1.13-2.40; P = .049). A positive blood culture was the only significant factor predicting treatment failure in acute hematogenous PJI (OR, 3.94; 95% CI, 1.18-13.1; P = .026) after adjusting for confounding variables. Kaplan-Meier survivorship for infection-free implant survivorship was 53.1% (95% CI, 38.3%-65.8%) at 1 year for all patients, 66.7% (95% CI, 45.7%-81.1%) for patients with negative blood cultures, and 36.4% (95% CI, 17.2%-55.7%) for patients with positive blood cultures (P = .037).

Conclusion

The presence of positive blood cultures is associated with decreased treatment success of DAIR for acute hematogenous PJI. Patients with more comorbidities may need to be treated more aggressively for a favorable outcome.

Severe Obesity Increases Risk of Infection After Revision Total Hip Arthroplasty

27-08-2019 – Joris Bongers, Katrijn Smulders, Marc W. Nijhof

Journal Article

Background

The increasing prevalence of obesity has resulted in an increased number of revision total hip arthroplasties (r
THAs) performed in patients with a high body mass index (BMI). The aim of this study is to evaluate whether obesity negatively affects (1) complication rate, (2) reoperation and revision rate, and (3) patient-reported outcome in r
THA.

Methods

In this registry-based study, we prospectively followed 444 r
THAs (cup: n = 265, stem: n = 57, both: n = 122) performed in a specialized high-volume orthopedic center between 2013 and 2015. The number of complications, and reoperation and revision surgery was registered until 5 years postoperatively. Oxford Hip Score (OHS) was evaluated preoperatively, and at 1 and 2 years postoperatively. Patients were categorized based on BMI to nonobese (<30 kg/m2, n = 328), obese (30-35 kg/m2, n = 82), and severe obese (≥35 kg/m2, n = 34).

Results

Severe obese patients, but not obese patients, had higher risks of complications and re-revision than nonobese patients. In particular, the risk of infection following r
THA was higher in severe obese patients (24%) compared to nonobese patients (3%; relative risk, 7.7). Severe obese patients had overall poorer OHS than nonobese patients, but improvement in OHS did not differ between severe obese and nonobese patients. No differences between obese and nonobese groups on OHS were observed.

Conclusion

In our study, severe obesity was associated with an increased risk of infection following r
THA. Patients with high BMI should be counseled appropriately before surgery.

Clinical Survivorship of Aseptic Revision Total Knee Arthroplasty Using Hinged Knees and Tantalum Cones at Minimum 10-Year Follow-Up

29-07-2019 – Hussein Abdelaziz, Rodrigo Jaramillo, Thorsten Gehrke, Malte Ohlmeier, Mustafa Citak

Journal Article

Background

The reconstruction of severe bone loss utilizing porous tantalum cones in patients undergoing revision total knee arthroplasty (TKA) has been established in the last years. However, reports on a long-term follow-up to assess the durability of such implants when combined with hinged knee designs are lacking. The current study aimed to evaluate the results of a previous study cohort at a minimum follow-up of 10 years.

Methods

A retrospective review was performed. The initial study cohort comprised of 38 patients who underwent aseptic revision TKA between 2007 and 2009 at a single institution. After exclusion of the deceased patients and patients who were lost to follow-up, 25 patients with hinged knees and 32 cones implanted were included with a minimum follow-up of 10 years (mean = 126.5 months, range 120-142, standard deviation SD = 5.92). Survivorship was determined, and re-revisions were observed. Functional Knee Society Score was assessed.

Results

After a minimum of 10 years, 24 of 32 cones (75%) had survived without any exchange in 18 patients. Reasons for cone revision included aseptic loosening (5/32 cones; 15.6%) and periprosthetic joint infection (3/32 cones; 9.4%). In 4 of the five revisions due to aseptic loosening, pure hinged knees had been implanted. The mean functional Knee Society Score of the survivors was 69.6 points (range 10-100, SD = 30.85), and the average flexion ability of the knee was 92° (range 30°-120°, SD = 22.09).

Conclusion

Porous tantalum cones in revision TKA exhibited no favorable but reasonable long-term durability. Rotating-hinge designs should be used whenever possible to reduce the risk of aseptic loosening. Further comparative long-term analyses with other techniques or implants could inform us about the best treatment method.

Superior Survivorship for Posterior Stabilized Versus Constrained Condylar Articulations After Revision Total Knee Arthroplasty: A Retrospective, Comparative Analysis at Short-Term Follow-Up

06-08-2019 – Kyle N. Kunze, Faisal Akram, Brian C. Fuller, Justin Choi, Scott M. Sporer, Brett R. Levine

Journal Article

Background

The decision to use a posterior stabilized (PS) or constrained condylar knee (CCK) articulation in revision total knee arthroplasty (RTKA) has traditionally been based on surgeon preference and knee stability. The purpose of this study is to compare various outcomes and survivorship in RTKA with PS or CCK articulations.

Methods

A retrospective comparative study of RTKA with CCK or PS articulations (PS = 106/CCK = 147) was performed with minimum 2-year follow-up. Exclusion criteria were patients with rotating hinged implants or non-CCK/PS constructs. Multivariate logistic regression models were constructed to determine whether implant articulation influenced (1) complications, (2) aseptic loosening, and (3) re-revision. Kaplan-Meier estimates of cumulative implant survival were constructed with revision as the failure variable.

Results

PS articulation was an independent predictor of increased postoperative knee flexion (6.4°, P = .010) and the knee society functional score (10.0, P = .002). Survivorship was significantly reduced for CCK revision articulations when all-cause re-revision was the primary endpoint (P = .0003, log-rank test of equality). The primary reason for re-revision in the CCK cohort was a recurrent/persistent infection of the operative knee (N = 16, 37.2%), followed by aseptic loosening (N = 13, 30.2%). PS articulations conferred a lower likelihood of re-revision (odds ratio OR 0.3, P = .001), but articulation design was not associated with complications (OR 0.5, P = .123) or aseptic loosening (OR 2.6, P = .143).

Conclusion

The PS articulation when used for appropriate indication conferred superior survivorship for the primary endpoint of all-cause re-revision and overall knee function when compared to the CCK articulation after RTKA. Implant articulation was not a predictor of aseptic loosening or complications.

Quadriceps Snip in 321 Revision Total Knee Arthroplasties: A Safe Technique in a Matched Cohort Study

07-08-2019 – Matthew P. Abdel, Anthony Viste, Christopher G. Salib, Daniel J. Berry

Journal Article

Background

Quadriceps snips (QSs) are commonly used to gain enhanced exposure during revision total knee arthroplasties (TKAs). The goals of this study were to evaluate the longer-term clinical outcomes and complications in a contemporary cohort of patients treated with QS and to compare them to a matched cohort treated with standard exposure during revision TKAs.

Methods

We retrospectively identified 3107 revision TKAs performed at our institution between 2002 and 2012. QS was performed in 321 of these knees. Each QS revision TKA was 1:1 matched to a control (standard exposure) based on age, gender, body mass index, surgery date, and reason for revision. Clinical outcomes studied included Knee Society Score, range of motion, and extensor lag. Other outcomes assessed were complications (especially extensor mechanism disruption) and survivorship. Mean follow-up was 5 years.

Results

The mean Knee Society Score improvement was not significantly different between groups (P = .9). At latest follow-up, the mean range of motion was 93° in the QS group and was slightly higher at 100° in the control group (P = .002). Postoperative extensor lag of 10 degrees or more was present in 21 (6.7%) QS knees versus 19 (6.8%) control knees (P = .95). Complication rates were similar in both groups with extensor mechanism disruption occurring in 3 in the QS group (0.7% at 10 years) versus 4 in the control group (0.8% at 10 years; P = .91). Kaplan-Meier survivorships free of revision for aseptic loosening, free of any revision, and free of any reoperation were similar at 10 years (85%, 71%, and 61%, respectively, in the QS group vs 89%, 70% and 60%, respectively, in the control group).

Conclusion

This matched cohort study is the largest to report the results of QS and also the largest to report results compared with patients treated with standard exposure. Building on the results of smaller historical series, this study demonstrates QS was a facile technique in complex revision TKAs allowing for safe exposure with few complications.

Level of Evidence

III (case-control study).

Tibial Tubercle Osteotomy vs the Extensile Medial Parapatellar Approach in Revision Total Knee Arthroplasty: Is Tibial Tubercle Osteotomy a Harmful Approach?

12-08-2019 – Keun-Churl Chun, Seok-Hyun Kweon, Dae-Jin Nam, Hyun-Tak Kang, Churl-Hong Chun

Journal Article

Background

As the frequency of total knee arthroplasty (TKA) is increasing, long-term follow-up of patients has become essential, and the frequency of revision total knee arthroplasty (R-TKA) due to the occurrence of various complications has also increased. There is controversy regarding which approach has minimal complications and an adequate visual field in R-TKA. Therefore, we compared the clinical and radiological results between the extensile medial parapatellar (EMP) approach and tibial tubercle osteotomy (TTO) for R-TKA.

Methods

Between March 1, 2000, and December 31, 2015, we compared 35 patients who underwent the EMP approach and 31 who underwent the TTO approach for R-TKA. In this study, the preoperative range of motion (ROM) was an important criterion for the choice of approach in R-TKA. The EMP approach was applied to patients with a ROM above 60°. The TTO approach was applied to patients with knee flexion limited to 0°-30°. We clinically assessed knee ROM, Knee Society scores, and Hospital for Special Surgery scores at the time of the last follow-up. We radiographically measured femorotibial alignment and patellar height. We also examined the complication rates. The average length of the TTO was 1.0 × 2.5 cm × 10 cm. We used 3 or more 3.5-mm half-threaded screws.

Results

The mean postoperative ROM of the knee joint at the time of the last follow-up was 103° (flexion contracture 5° and further flexion 108°) in the group that underwent the EMP approach and 101° (flexion contracture 4° and further flexion 109°) in the group that underwent the TTO approach. The mean Knee Society scores were 86 (71-96) and 85 (72-94), and the mean Hospital for Special Surgery scores were 82 (70-93) and 83 (68-92) for the 2 groups, respectively, with no statistically significant difference. The mean femorotibial angles were 0.6° (±3.3°) and 0.1° (±2.9°), and the mean Insall-Salvati ratios were 1.0 (±0.34) and 0.8 (±0.14), respectively, with no statistically significant difference. The group that underwent TTO achieved bone union at an average of 11.8 weeks after surgery. In the group that underwent the EMP approach, 2 patients had extensor lag of more than 10°. In the group that underwent TTO, 2 subjects had skin necrosis at the operative site.

Conclusion

The clinical and radiological outcomes were similar in the 2 groups after R-TKA. To increase the ROM and obtain adequate exposure, TTO is also considered a useful surgical approach. However, complications related to TTO should be minimized.

Level of Evidence

Therapeutic level III, retrospective comparative study.

Minimum 15-Year Results of a Dual-Offset Uncemented Femoral Stem in Total Hip Arthroplasty

27-08-2019 – Phonthakorn Panichkul, Richard W. McCalden, Steven J. MacDonald, Lyndsay E. Somerville, Douglas N. Naudie

Journal Article

Background

The aim of the present study is to assess the long-term clinical and radiological outcomes of a proximal porous-coated, dual-offset, tapered titanium alloy uncemented stem at a minimum of 15 years of follow-up.

Methods

We reviewed 210 total hip arthroplasties (in 193 patients) performed between 1996 and 1999 and followed prospectively in our database who received the Synergy stem. We report a Kaplan-Meier survival analysis as well as the Harris Hip Score, the Western Ontario and Mc
Master University Arthritis Index, and the Short Form Health Survey-12 scores. Radiographs were evaluated for evidence of subsidence, osteolysis, osteointegration, or loosening.

Results

The average follow-up was 16 years (range, 15-17.7 years). Kaplan-Meier survival analysis with revision of stem for aseptic mechanical loosening (1 stem) as the end point revealed a cumulative survival rate of 99.5% at 16 years. The Harris Hip Score, the Western Ontario and Mc
Master University Arthritis Index, and the Short Form Health Survey-12 physical scores were all significantly improved (P < .001) from the preoperative period to latest follow-up. Minor osteolysis was observed proximally in 14 hips (6.6%) with no osteolysis distal to the porous coating.

Conclusion

To our knowledge, this study represents the largest series reporting the longest clinical follow-up of this third-generation, dual-offset, proximal ingrowth, tapered cementless stem. The Synergy stem design has achieved excellent clinical outcomes, predictable osteointegration, and outstanding survivorship of 99.5% at a minimum of 15 years follow-up, representing the standard for femoral stems at our institution.

Midterm Clinical and Radiographic Outcomes of a Contemporary Monoblock Dual-Mobility Cup in Uncemented Total Hip Arthroplasty

25-08-2019 – Michel-Henri Fessy, Laurent Jacquot, Jean-Charles Rollier, Julien Chouteau, Tarik Ait-Si-Selmi, Hugo Bothorel, Jean-Christophe Chatelet

Journal Article

Background

The efficacy of contemporary monoblock dual-mobility (DM) cups to prevent dislocations in total hip arthroplasty (THA) is well reported, but there is little published data on their mid- to long-term outcomes. The authors aimed at reporting the 10-year survival of a contemporary DM cup as well as its clinical and radiographic outcomes.

Methods

From a retrospective consecutive multicentric series of 516 patients (541 hips) that received uncemented THA between June 2007 and June 2010, 6 patients (6 hips) had cup and stem revisions, 5 patients (5 hips) had isolated stem revision, and 2 patients (2 hips) had isolated insert revision. A total of 103 patients (111 hips) died with their original implants, and 41 patients (42 hips) were lost to follow-up. This left 358 patients (375 hips) for clinical assessment at a median follow-up of 8.7 years (range, 6.8-10.5 years), including 279 patients (290 hips) with postoperative radiographs. Implant survival was calculated using the Kaplan-Meier method, and multivariable analyses were performed to determine whether clinical outcomes are associated with patient or surgical factors.

Results

The 10-year survival considering revision for aseptic loosening as end point was 100% for the cup and 99.2% for the stem. No dislocations were observed, and radiographic assessment revealed 1 acetabular granuloma (0.3%), but no radiolucencies nor fractures. The Harris hip score improved from 49.6 ± 15.5 to 85.2 ± 14.5, and the postoperative Oxford hip score was 19.2 ± 7.6. Multivariable analyses revealed that improvement in Harris hip score increased with cup diameter (beta, 1.28; P = .039).

Conclusion

Our data confirmed satisfactory midterm outcomes of uncemented THA using a contemporary DM cup, with no dislocations nor cup revisions due to aseptic loosening.

Level of Evidence

Level IV, retrospective cohort study.

Aspirin Thromboprophylaxis Confers No Increased Risk for Aseptic Loosening Following Cementless Primary Hip Arthroplasty

07-08-2019 – Karan Goswami, Timothy L. Tan, Alexander J. Rondon, Noam Shohat, Michael Yayac, Patrick K. Schlitt, P. Maxwell Courtney

Journal Article

Background

Aspirin has been shown to be a safe and cost-effective thromboprophylaxis agent with equivalent preventive efficacy to warfarin and fewer side-effects. However, animal studies have suggested delayed bone healing with aspirin and other inhibitors of prostaglandin synthesis. The impact of aspirin on aseptic loosening following cementless total hip arthroplasty (THA) has yet to be explored. Our aim was to determine if patients receiving aspirin for thromboprophylaxis had higher rates of aseptic loosening vs patients receiving warfarin after THA.

Methods

We identified 11,262 consecutive primary uncemented THA performed between 2006 and 2017. Postoperatively, either warfarin (target international normalized ratio 1.5-2.0) or aspirin chemoprophylaxis were prescribed for 4 weeks. We recorded demographics, length of stay, body mass index, preoperative nonsteroidal antiinflammatory drug use, and Elixhauser comorbidity index. All revisions because of aseptic loosening within 1 year of the index procedure were identified radiographically, confirmed intraoperatively, and did not fulfill Musculoskeletal Infection Society criteria for periprosthetic infection. Multivariate logistic regression analysis was performed.

Results

There was no difference (P = .14) in the rates of revision for aseptic loosening between patients in the aspirin cohort (14/4530; 0.31%; P = .14) and the warfarin cohort (36/6682; 0.54%). After accounting for confounding variables, no significant difference was noted in aseptic loosening rates between patients treated with aspirin vs those treated with warfarin (adjusted odds ratio 0.51; P = .11). Perioperative nonsteroidal antiinflammatory drug was not significantly associated with aseptic loosening (adjusted odds ratio 1.20; P = .67).

Conclusion

While multiple agents are available for venous thromboprophylaxis, there is increasing evidence in favor of the use of aspirin. This study allays the notion that aspirin increases the rates of aseptic loosening following uncemented hip arthroplasty.

Return to Sport After Bilateral Single Stage Total Hip Arthroplasty Using the Direct Anterior Approach: A Case Control Study

22-07-2019 – Cécile Batailler, Anouk Rozinthe, Marcelle Mercier, Christopher Bankhead, Romain Gaillard, Sébastien Lustig

Journal Article

Background

Total hip arthroplasty (THA) is currently performed on active patients with increasing functional demands. Single stage bilateral THA is indicated in younger patients in good general health. Our objective is to evaluate the return to sport (RTS) in patients who underwent bilateral single stage THA compared to unilateral THA.

Methods

This retrospective case control study was conducted between 2013 and 2017. All patients who underwent bilateral single stage THA were included. The control group had unilateral THA performed and was matched based on age, body mass index, gender, and surgery date (2 controls for each bilateral case). All surgeries were performed by a single senior surgeon using the direct anterior approach. The University of California Los Angeles activity score was collected at the last follow-up. A questionnaire regarding RTS, motivation, and satisfaction was assessed.

Results

Thirty-two patients were included in the study, of whom 21 were men. The average age was 60.7 ± 9.6 years, body mass index was 26 ± 4 kg/m2, and mean follow-up was 20.1 ± 11.6 months. Twenty-eight patients overall (87%) returned to sport after the procedure. Twenty-five of these (89%) returned to the same sport, and 17 (68%) participated at the same intensity. The average time to RTS was 4 ± 2.8 months. These results were at least as good as those after unilateral THA. The level of motivation of the patient was the only predictive factor for RTS (P < .001).

Conclusion

Bilateral single stage THA via a direct anterior approach allows for RTS and to a similar level in the majority of patients in whom this procedure is indicated.

Level of Evidence

Comparative retrospective study, Level III.

Complications and Costs Are Not Increased After Total Hip Arthroplasty in Patients With a History of Prostate Cancer

22-07-2019 – Samuel Rosas, Shane Tipton, T. David Luo, Johannes F. Plate, Jeffrey S. Willey, Cynthia L. Emory

Journal Article

Background

Prostate cancer (PCa) is a largely prevalent disease in the United States. Moreover, it is unclear whether the thromboembolic burden of disease remains present after the cancer has been treated and whether such state impacts the short-term outcomes of orthopedic procedures. Therefore, the purpose of this study is to assess 90-day postoperative complications and costs after total hip arthroplasty (THA) for osteoarthritis in patients with a history of PCa.

Methods

Two groups of patients who underwent THA for osteoarthritis in the Medicare Standard Analytical Files were identified through the Pearl
Diver server. Both groups were matched based on age, diabetes, smoking status, chronic kidney disease, alcohol abuse, chronic liver disease, and obesity in order to create a case-control study comparison. The 90-day complication rates after THA were compared using univariate regressions (odds ratio). We hypothesized that patients with a history of PCa would develop increased rates of thromboembolic complications based on a prolonged procoagulative state.

Results

After matching, each group was comprised of 62,571 patients. Our findings identified greater 90-day pneumonia rates for those without a history of PCa (3.26% vs 2.68%; odds ratio, 0.82). All other complications including thromboembolic diseases were clinically comparable in both groups during the 90-day postoperative period. The charges and reimbursements for the 90-day period were also comparable.

Conclusion

In our large case-control study of 125,142 patients, we found that patients with a history of PCa do not have increased risk of short-term complications after THA and that the mean 90-day reimbursements were similar for both groups at $14,153 for PCa patients and $14,033 for those without (P = .114).

Advantages of an Anterior-Based Muscle-Sparing Approach in Transitioning From a Posterior Approach for Total Hip Arthroplasty: Minimizing the Learning Curve

07-08-2019 – Ryland P. Kagan, Eric M. Greber, Stephen M. Richards, Jill A. Erickson, Mike B. Anderson, Christopher L. Peters

Journal Article

Background

Enthusiasm for anterior-based approaches for total hip arthroplasty (THA) continues to increase but there is concern for increased complications during the learning curve period associated. This study aimed to investigate if there was a difference in perioperative variables, intraoperative and immediate postoperative complications, or patient-reported outcomes when transitioning from a mini-posterior approach (m
PA) to an anterior-based muscle-sparing (ABMS) approach for THA.

Methods

Retrospective cohort study on the first 100 primary THA cases (n = 96 patients) of the senior author (August 2016 to August 2017) using the ABMS approach. These cases were compared to primary THA cases done the year prior (July 2015 to July 2016, n = 91 cases in 89 patients) using an m
PA. Data were extracted and analyzed via gamma regression with robust standard errors and using generalized estimating equation regression.

Results

We found no difference in the estimated blood loss (P = .452) and surgical time (P = .564) between the cohorts. The ABMS cases had a slightly shorter length of stay (P = .001) with an adjusted mean length of stay of 1.53 days (95% confidence interval 1.4-1.6) compared to 1.85 days (95% confidence interval 1.8-1.9) in the m
PA cases. There was no difference in the frequency of immediate postoperative complications (all, P > .05). There was no difference in the adjusted mean change in patient-reported outcomes (all P > .05). In the ABMS group, there was no difference in surgical time or physical function computerized adaptive test between the first 20 cases (reference) and each subsequent group of 20 cases (all P > .05).

Conclusion

This study demonstrates no associated learning curve for an experienced senior surgeon when switching routine THA approach from m
PA to ABMS. We advise careful interpretation of our results, as they may not apply to all surgeons and practices.

Level of Evidence

Level III Therapeutic Study: retrospective comparative study.

Opioid Disorders Are Associated With Thromboemboli Following Primary Total Knee Arthroplasty

28-08-2019 – Rushabh M. Vakharia, Karim G. Sabeh, Wayne B. Cohen-Levy, Nipun Sodhi, Michael A. Mont, Martin W. Roche

Journal Article

Background

Opioid use disorder (OUD) is defined as a problematic pattern of opioid abuse and dependency leading to problems or distress. The purpose of this study is to investigate whether OUD patients undergoing primary total knee arthroplasty (TKA) have higher rates of venous thromboembolisms (VTEs), readmissions, and costs of care.

Methods

Patients undergoing TKA with OUD were identified and matched to controls in a 1:4 ratio according to age, gender, comorbidity index, and comorbidities within the Medicare database. Ninety-day VTEs, 90-day readmissions, and costs of care were compared. A P-value less than .01 was considered statistically significant.

Results

The study yielded 54,480 patients with (n = 10,929) and without (n = 43,551) OUD undergoing primary TKA. Matching was successful as there were no significant differences in baseline characteristics. OUD patients were found to have greater odds of VTEs (odds ratio 2.27, P < .0001) 90 days following primary TKA. OUD patients were found to have greater odds of 90-day readmissions (odds ratio 1.39, P < .0001) in addition to incurring higher day of surgery ($13,360.73 vs $11,911.94, P < .0001) and 90-day costs ($18,380.89 vs $15,565.57, P < .0001) compared to controls.

Conclusion

After adjusting for confounders, this analysis of 54,480 patients identified that patients with OUD have higher rates of VTEs, readmissions, and costs following primary TKA. In addition to using these data to help educate and counsel patients, the study should be used to help further regulate and control opioid prescriptions written by healthcare professionals.

Asynchronous Bilateral Total Knee Arthroplasty: Predictors of the Functional Outcome and Patient Satisfaction for the Second Knee Replacement

25-07-2019 – Nicholas D. Clement, Katie L. Merrie, David J. Weir, James P. Holland, David J. Deehan

Journal Article

Background

The primary aim of this study is to identify independent preoperative predictors of outcome and patient satisfaction for the second total knee arthroplasty (TKA).

Methods

A retrospective cohort of 454 patients undergoing an asynchronous (6 weeks or more apart) bilateral primary TKA were identified from an arthroplasty database. Patient demographics, comorbidities, Western Ontario and Mc
Master Universities Osteoarthritis Index (WOMAC), and Short Form-12 scores were collected preoperatively and 1 year postoperatively. Overall patient satisfaction was assessed at 1 year.

Results

The 1 year WOMAC pain score (P = .01), and improvement in WOMAC pain (P < .001) and functional (P = .002) scores were significantly lower for the second TKA. Worse preoperative WOMAC pain, function, and stiffness scores were demonstrated to be independent predictors of improvement in the WOMAC pain, function, and stiffness scores, respectively, for both the first and second TKA. The overall rate of satisfaction with the first TKA was 94.0% and 94.7% for the second TKA (P = .67). The rate of satisfaction for the second TKA was 77.8% for patients that were dissatisfied with their first TKA, which was an independent predictor of dissatisfaction (P = .02).

Conclusion

Improvement in pain and function is less with the second TKA, but the satisfaction rate remains similar. There are common independent predictors for change in the WOMAC score for the first and second TKA; however, the predictors of satisfaction were different with no common factors. Patients that were dissatisfied with their first TKA were more likely to be dissatisfied with their second TKA.

Level of Evidence II

Prognostic retrospective cohort study.

Bilateral Simultaneous vs Staged Total Knee Arthroplasty: Minimal Difference in Perioperative Risks

29-07-2019 – Ellen L. Tsay, Trevor R. Grace, Thomas Vail, Derek Ward

Journal Article

Background

With the rising utilization of total joint arthroplasty, the role of simultaneous-bilateral surgery will have an expanding impact. The purpose of this study is to examine the risks of perioperative complications with this approach in total knee arthroplasty (TKA), to inform shared decision-making.

Methods

We reviewed national hospital discharge data from 2005 to 2014 to compare outcomes between simultaneous-bilateral TKAs (sim-BTKAs) and staged-bilateral TKAs (staged-BTKAs). Hierarchical logistic regression analyses were used to adjust for confounders. Outcomes analyzed included mortality, various medical complications, knee infection, and mechanical complications.

Results

This study analyzed 27,301 sim-BTKAs and 45,419 staged-BTKAs. Patients who underwent simultaneous surgery had a statistically significant higher adjusted odds of mortality, cardiac events, thromboembolic events, and complications involving the urinary and digestive systems, and a lower adjusted odds of deep knee infection and hematoma. Thirteen of the 14 complications had overall incidences less than 2% and 1 outcome had an incidence of 3%. The absolute between-group risk difference for any complication was 1% or less.

Conclusion

Sim-BTKAs have a statistically significant increased odds of multiple complications compared to staged-BTKAs. However, the absolute risk differences between these options are minimal and the occurrence of any complication is low.

Level of Evidence

Therapeutic Level III.

A One-Question Patient-Reported Outcome Measure Is Comparable to Multiple-Question Measures in Total Knee Arthroplasty Patients

24-08-2019 – Daniel C. Austin, Michael T. Torchia, Paul M. Werth, Adriana P. Lucas, Wayne E. Moschetti, David S. Jevsevar

Journal Article

Background

Patient-reported outcome measures (PROMs) are important for tracking outcomes following total knee arthroplasty (TKA) but can be limited by time constraints and patient compliance. We sought to evaluate the utility of the one-question, modified single assessment numerical evaluation (M-SANE) score in TKA patients compared to legacy PROMs.

Methods

Patients undergoing TKA completed the Patient-Reported Outcomes Measurement Information System-10 (PROMIS-10), the Knee Disability and Osteoarthritis Outcomes Score Junior (KOOS Jr), and M-SANE (modified-SANE) assessments both preoperatively and postoperatively. The M-SANE score asked patients to rate their native or prosthetic knee on a scale from 0 to 10, with 10 being the best function. M-SANE validity was determined by the Spearman’s correlation between the collected PROMs and the Bland-Altman plots. PROM responsiveness was assessed using the standardized response mean.

Results

In total, 217 patients completed PROMs preoperatively and at 1 year postoperatively. Floor and ceiling effects of the M-SANE were higher than other PROMs but still relatively low (4%-11%). There was a moderate to strong correlation at nearly all time points between the M-SANE and KOOS Jr (ρ = 0.44-0.78, P < .001). There was a weak correlation between the M-SANE and PROMIS physical component summary at the preoperative evaluation (ρ = 0.28) but a strong correlation at 1-year follow up (0.65, P < .001). The long-term responsiveness of the M-SANE to TKA (standardized response mean SRM = 0.98, 95% confidence interval CI 0.80-1.17) was comparable to both the KOOS Jr (SRM = 1.19, 95% CI 1.00-1.38) and PROMIS physical component summary (SRM = 0.82, 95% CI 0.74-0.91). Bland-Altman plots demonstrated that the M-SANE and KOOS Jr capture combined knee pain and functionality differently.

Conclusion

The M-SANE score was comparable to validated multiple-question PROMs in TKA patients. The demonstrated validity of the M-SANE, as well as its comparable responsiveness to more lengthy PROMs, highlights its use as a one-question PROM for assessment of patient undergoing TKA.

Same-Day Physical Therapy Following Total Knee Arthroplasty Leads to Improved Inpatient Physical Therapy Performance and Decreased Inpatient Opioid Consumption

21-08-2019 – Nana O. Sarpong, Akshay Lakra, Emma Jennings, H. John Cooper, Roshan P. Shah, Jeffrey A. Geller

Journal Article

Background

Early ambulation with physical therapy (PT) following total knee arthroplasty (TKA) has demonstrated benefits in the literature. However, the impact of early PT on rehabilitation performance and opioid consumption has not been elucidated. We evaluate the effect of same-day PT on inhospital functional outcomes and opioid consumption.

Methods

We retrospectively identified 2 cohorts of primary TKA patients from July 2016 to December 2017: PT0 (n = 295) received PT on the day of surgery, and PT1 (n = 392) received PT on postoperative day (POD) 1. Outcomes studied included number of feet walked on POD0-3, visual analog scale pain scores, morphine equivalents (ME) consumed, length of stay, and discharge disposition. Analysis was conducted using the Student t-test and Fisher exact test.

Results

In comparison to the PT1 group, the PT0 group walked significantly more steps on POD1 (347.6 vs 167.4 ft, P < .0001), POD2 (342.1 vs 203.5 ft, P < .0001), and POD3 (190.3 vs 128.9 ft, P = .00028). There was no difference between the 2 groups for visual analog scale. The PT0 group also consumed significantly fewer total ME when compared to the PT1 group (149.0 vs 200.3 mg, P = .0002). The PT0 group had a significantly shorter length of stay when compared to the PT1 group (2.7 vs 3.2 days, P = .00075). More patients were discharged home in the PT0 group (81.7% vs 54.8%, P < .0001).

Conclusion

We observed that initiation of PT on POD0 led to better PT performance, reduced ME during hospitalization, and more patients discharged home.

Level of Evidence

III, Retrospective cohort study.

Preoperative Radiological Parameters Predicting the Need for Lateral Retinacular Release in Total Knee Arthroplasty

26-08-2019 – Natesan Rajkumar, Dhanasekaran Soundarrajan, Palanisami Dhanasekararaja, Shanmuganathan Rajasekaran

Journal Article

Background

Proper patellar tracking is essential for well-functioning total knee arthroplasty (TKA). Besides implanting components in the correct position and rotation, balancing parapatellar soft tissues is also important in aiding normal patellar tracking. Patellar maltracking during TKA can be improved by lateral retinacular release (LRR).

Methods

We studied the incidence of LRR in consecutive primary TKA with nonresurfaced patella and posterior-stabilized implant design. We analyzed data from 250 consecutive primary TKAs (212 patients) from January 2016 to May 2016. We evaluated the preoperative radiological parameters like patellar tilt, patellar shift, patellar morphology, Insall-Salvati ratio, femoro-tibial angle, distal femoral valgus angle, and proximal tibia varus angle which predict the need for LRR during TKA. We used multivariate regression analysis to find the association of individual radiological parameters and the LRR.

Results

The need for LRR is significantly associated with preoperative radiological parameters like patellar shift and patellar tilt (P < .001). Compared to the nonreleased group, the adjusted odds of LRR were greater for morphological parameters like Wiberg type 3 patella (odds ratio OR 17.45, 95% confidence interval CI 7.21-42.20), lateral facet thinning (OR 4.38, 95% CI 2.37-8.07), lateral patellofemoral arthritis (OR 14.36, 95% CI 6.82-30.23), and coronal valgus deformity (OR 4.95, 95% CI 1.60-10.68).

Conclusion

Preoperative assessment of these radiological parameters in the axial view implies a high chance of tight lateral retinacular structures. This helps in identifying patients who have a higher likelihood for patellar maltracking during TKA. Appropriate LRR helps to provide better patellar tracking post TKA.

Higher Rate of Early Revision Following Primary Total Knee Arthroplasty in Patients Under Age 55: A Cautionary Tale

30-07-2019 – Ryan S. Charette, Matthew Sloan, Ryan D. DeAngelis, Gwo-Chin Lee

Journal Article

Background

There has been an increased number of total knee arthroplasties (TKAs) performed in young and active patients. Although improved materials have decreased the likelihood of early catastrophic wear, concerns remain with the performance and survivorship of TKA implants in this patient population. The purpose this study is to evaluate perioperative complications, patient-reported outcomes, and implant survivorship of TKAs performed in patients under age 55.

Methods

We retrospectively reviewed 4259 primary TKAs performed over a 4-year period. There were 741 TKAs in patients under age 55. The primary outcome of interest was rate of revision at 30 days, 1, 2, and 5-year time points. Secondary outcomes included postoperative transfusion rate, length of stay, rate of deep vein thrombosis/pulmonary embolism, need for manipulation under anesthesia, readmission and reoperation within 30 days, as well as patient-reported outcomes.

Results

There were 3518 patients over 55 years and 741 patients under 55 years. Overall, 175 patients required revision (4.1%). Patients under 55 years had significantly higher cumulative revision rate at 1 (3.4% vs 1.8%, P < .001), 2 (5.0% vs 2.4%, P < .001), and 5 years (7.3% vs 3.7%, P < .001). Patients under 55 years had a higher rate of early reoperation. Patients over 55 years required more transfusions and suffered a higher rate of early deep vein thrombosis. Patients over 55 years had significantly greater improvements in Patient Reported Outcome Measurement Information System Global 10 Physical scores at 6 months postoperatively compared to patients under 55 years.

Conclusions

Despite improvements in TKA implants, young and active patients remained at higher risk of early revision compared to older patients. The data should be used to counsel young prospective TKA patients about the early risk of reoperation and non–wear-related complications.

The Clinical Outcome of Patellofemoral Arthroplasty vs Total Knee Arthroplasty in Patients Younger Than 55 Years

11-09-2019 – Ivan Kamikovski, Johanna Dobransky, Geoffrey F. Dervin

Journal Article

Background

Patellofemoral osteoarthritis affects 10% of patients older than 40 years and is commonly treated by patellofemoral joint arthroplasty (PFA) or a total knee arthroplasty (TKA). PFA is a more conservative approach with documented faster recovery. No study to date has compared both approaches with respect to patient-reported outcome measures in patients younger than 60 years.

Methods

A retrospective case-matched cohort based on age, sex, body mass index, and side of 23 PFAs (in 19 patients) operated on by 2 surgeons and of 23 TKAs (23 patients) operated on by 6 surgeons was included in the study. All patients were younger than 55 years and operated on between March 2010 and September 2015. The Western Ontario and Mc
Master Osteoarthritic Index, Knee injury and Osteoarthritis Outcome scores, Tegner, and University of California, Los Angeles activity scores were compared between preoperative and minimum 2-year postoperative timepoints between groups.

Results

TKA and PFA were comparable on all patient-reported outcome measures at minimum 2-year follow-up; however, PFA patients exhibited statistically significantly larger improvement between 1 year postoperative and 2 years postoperative timepoints (P < .05). All patients improved between preoperative and postoperative timepoints (P < .05).

Conclusion

Although TKA performed better with respect to functional outcomes at the 1-year mark, at 2-year follow-up, PFA and TKA performed equally well. Our results allow us to conclude that in younger patients with isolated patellofemoral osteoarthritis who desire a more conservative, kinematic-preserving approach, PFA continues to be a practical treatment option yielding early outcomes that compare favorably with TKA.

The Effect of Posterior Tibial Slope on Joint Gap and Range of Knee Motion in Mobile-Bearing Unicompartmental Knee Arthroplasty

14-08-2019 – Takashi Suzuki, Keinosuke Ryu, Kei Kojima, Hisayuki Oikawa, Shu Saito, Masahiro Nagaoka

Journal Article

Background

It is widely known that the posterior tibial slope (PTS) has an influence on the clinical outcome of arthroplasty. However, the influence of PTS on unicompartmental knee arthroplasty (UKA) is still not fully clear. The objective of this study is to reveal the effect PTS has on knee flexion and extension joint gap and the postoperative range of motion in mobile-bearing UKA. Moreover, we investigated an adequate PTS angle in mobile-bearing UKA.

Methods

Oxford UKA was performed so that the flexion gap would be equal to the extension gap. Correlation between the gap value difference from 90° to 120° of the knee flexion and the PTS was evaluated. Correlation between postoperative range of motion and the PTS was also evaluated to find whether a small degree of PTS would cause knee flexion restriction.

Results

The PTS had a moderate positive correlation with the flexion gap difference. However, the PTS had no correlation with the knee flexion angle both postoperative and 1 year after surgery.

Conclusion

It was suggested that the degree of the PTS should not be so large to avoid joint looseness throughout every knee angle. Increasing the degree of the PTS had the potential to dislocate the bearing. Since a small degree of the PTS does not have an influence on the clinical outcome, surgeons should aim to cut the tibia with a posterior slope of less than 7°.

Better Implant Positioning and Clinical Outcomes With a Morphometric Unicompartmental Knee Arthroplasty. Results of a Retrospective, Matched-Controlled Study

28-08-2019 – Jean-Charles Escudier, Christophe Jacquet, Xavier Flecher, Sebastien Parratte, Matthieu Ollivier, Jean-Noel Argenson

Journal Article

Background

During medial unicompartmental knee arthroplasty (UKA), tibial tray implantation requires compromise between bone coverage and rotational position. It was hypothesized that morphometric tibial tray (MTT) would improve implant positioning and subsequently clinical outcomes as compared to symmetric tibial tray (STT).

Methods

A total of 106 patients who underwent medial UKA in our department between January 2017 and March 2018 were included matched on gender and age (53 in each group). Inclusion criteria were symptomatic medial femorotibial osteoarthritis, functional anterior cruciate ligament, primary arthritis, or osteonecrosis. Rotation of the tibial implant, tibial bone coverage, medial and posterior overhang were assessed with a postoperative computed tomography scan. The Knee Society Score (KSS), the Knee injury and Osteoarthritis Outcome Score Short Form (KOOS SF), and the quality of life score Euro
QoL 5-Dimensions 3-Levels (EQ5D3L) were assessed at a minimum of 1-year follow-up.

Results

Implants of the STT group exhibited more external rotation (6.3° ± 4.02° vs 4.6° ± 3.59°; P = .04), and medial and posterior overhang >3 mm (35% vs 0% and 22% vs 0%; P < .0001) but no difference for tibial bone coverage (97.3% ± 11.35% vs 94.7% ± 10.89%; P = .23). Global KSS (188.6 ± 6.6 vs 175.2 ± 31.7; P < .01), KOOS SF (16.9 ± 6.1 vs 22.5 ± 11.8; P < .003), and EQ5D3L (1 ± 0.1 vs 0.9 ± 0.2; P < .001) were higher in MTT group. According to the multivariate analysis, MTT had a positive independent effect on the KSS, KOOS SF, and EQ5D3L.

Conclusion

The use of an MTT in medial UKA allowed better implant positioning when decreasing the rate of overhang; superior short-term clinical outcomes were found as compared to STT.

Perioperative Selective Serotonin Reuptake Inhibitor Use Is Associated With an Increased Risk of Transfusion in Total Hip and Knee Arthroplasty

04-09-2019 – Elshaday S. Belay, Colin T. Penrose, Sean P. Ryan, Michael A. Bergen, Michael P. Bolognesi, Thorsten M. Seyler

Journal Article

Background

Selective serotonin reuptake inhibitors (SSRIs) have been shown in both orthopedic and general surgery literature to be associated with an increased risk of blood loss, and this is thought to occur via diminished platelet serotonin reuptake and subsequent decline in platelet aggregation potential. In this study, we aim at quantifying the effect of treatment with SSRIs on blood loss and transfusion rates following total hip (THA) or total knee arthroplasty (TKA).

Methods

THA (4485) and TKA (5584) cases from January 2013 to December 2017 at the investigating institution were queried and analyzed separately from an institutional database. Patients were stratified by utilization of an SSRI at the time of surgery. Patient demographics, baseline coagulopathy, preoperative and postoperative hemoglobin, transfusion, and length of stay were obtained to compare the 2 cohorts.

Results

The transfusion rate for SSRI users was 3.9% in the TKA group and 8.5% in the THA group. After controlling for age, gender, body mass index, presence of coagulopathy, procedure (THA vs TKA), and SSRI status, SSRI utilization was significantly associated with increased blood loss (P < .004), and logistic regression controlling for the same variables showed SSRI utilization to be predictive of transfusion (odds ratio, 1.476; P < .001).

Conclusion

SSRI utilization was associated with increased perioperative blood loss and predictive of transfusion risk, particularly with THA. This represents an important factor that may be modified in the setting of total joint arthroplasty but further work will be necessary to study potential alternative medications for depression in the perioperative phase.

Response to the Letter to the Editor on “Advanced Age Is Not a Barrier to Total Knee Arthroplasty: A Detailed Analysis of Outcomes and Complications in an Elderly Cohort Compared With Average Age Total Knee Arthroplasty Patients”

01-10-2019 – Antonio Klasan, Sven E. Putnis, Wai W. Yeo, Brett A. Fritsch, Myles R. Coolican, David A. Parker

Letter

Impact of Bariatric Surgery on Inpatient Complication, Cost, and Length of Stay Following Total Hip or Knee Arthroplasty

24-08-2019 – Yicun Wang, Zhantao Deng, Jia Meng, Qiying Dai, Tao Chen, Nirong Bao

Journal Article

Background

Morbid obesity is an important risk factor for arthroplasty and also closely associated with worse postoperative outcomes. Bariatric surgery is effective in losing weight and decreasing comorbidities associated with obesity. However, no study had demonstrated the influence of bariatric surgery on the outcome of arthroplasty in a large population.

Methods

We used 2006-2014 discharge records from the Nationwide Inpatient Sample, and identified study population and inpatient complications by International Classification of Diseases, 9th Revision, Clinical Modification diagnosis/procedure codes. Propensity score analysis was used to match total hip arthroplasty (THA) or total knee arthroplasty (TKA) patients with morbid obesity and THA or TKA patients with bariatric surgery.

Results

Proportion of morbid obesity in both TKA and THA patients demonstrated a rising trend, while proportion of bariatric surgery in morbidly obese TKA and THA patients remains steady after 2007. For THA patients, there was fewer pulmonary embolism, more blood transfusion and anemia, and shorter length of stay in bariatric surgery group. For TKA patients, bariatric surgery group had a lower risk of pulmonary embolism, respiratory complications, death, and shorter length of stay, but bariatric surgery group had a higher risk of blood transfusion and anemia.

Conclusion

There is evidence that bariatric surgery prior to arthroplasty, especially THA, appears to reduce rates of pulmonary complications and length of stay. But anemia and blood transfusion seem to be more common in patients with prior bariatric surgery.

Preemptive Analgesia With Oxycodone Is Associated With More Pain Following Total Joint Arthroplasty

14-08-2019 – H. John Cooper, Akshay Lakra, Robert B. Maniker, Thomas R. Hickernell, Roshan P. Shah, Jeffrey A. Geller

Journal Article

Background

Preemptive multimodal analgesia (PMA) is a commonly used technique to control pain following total joint arthroplasty. PMA protocols use multiple analgesics immediately preoperatively to prevent central sensitization and amplification of pain during surgery. While benefits of some individual components of a PMA protocol have been established, there are little data to support inclusion or exclusion of opioids in this context.

Methods

This is a retrospective cohort study of 550 patients undergoing elective, primary total joint arthroplasty at a single institution using a standardized preoperative perioperative protocol. Two hundred seventy-five patients received oxycodone in addition to a standard multimodal preoperative analgesia regimen just before surgery and were compared to a matched cohort of 275 patients who received the standard regimen alone. Outcome measures included inpatient visual analog scale pain scores, inpatient opioid consumption, length of stay, and ambulation distance with physical therapy.

Results

Patients who received opioids in preoperative holding reported significantly greater visual analog scale pain scores on postoperative day 1 (3.7 vs 3.1; P = .01), when compared to those who did not. These patients also walked shorter distances on postoperative day 0 (59.5’ vs 125.7’; P < .001) and consumed greater morphine equivalents per hospital day over the course of their hospital stay (52.2 vs 37.2 mg; P < .001). These differences remained significant when stratified by procedure, total knee arthroplasty or total hip arthroplasty. Differences in pain and function between groups were more pronounced in patients undergoing total hip arthroplasty than those undergoing total knee arthroplasty.

Conclusion

Total joint patients who were given preemptive opioids immediately before surgery experienced more pain, consumed more postoperative opioids, and exhibited impaired early function as compared to those who were not given preemptive opioids. Orthopedic surgeons should reconsider routine use of preemptive opioids in this context.

Anesthesia and Analgesia Practices in Total Joint Arthroplasty: Axa0Survey of the American Association of Hip and Knee Surgeons Membership

03-08-2019 – Charles P. Hannon, Timothy C. Keating, Jeffrey K. Lange, Benjamin F. Ricciardi, Bradford S. Waddell, Craig J. Della Valle

Journal Article

Background

The purpose of this study is to survey the current analgesia and anesthesia practices used by total joint arthroplasty surgeon members of the American Association of Hip and Knee Surgeons (AAHKS).

Methods

A survey of 28 questions was created and approved by the AAHKS Research Committee. The survey was distributed to all 2208 board-certified adult reconstruction surgeon members of AAHKS in November 2018.

Results

There were 622 responses (28.2%) to the survey. A majority of respondents (93.2%, n = 576) use preemptive analgesia prior to total joint arthroplasty. Most respondents use a spinal for total knee arthroplasty (TKA) (74.4%) and total hip arthroplasty (THA) (72.6%). A peripheral nerve block is routinely used by 68.7% of respondents in primary TKA. Periarticular injection or local infiltration anesthesia is routinely used by 80.3% of respondents for both TKA and THA patients. The average number of opioid pills prescribed postoperatively after TKA is 49 pills (range 0-200) and after THA is 44 pills (range 0-200). Most surgeons (58%) expect that this prescription should last for 2 weeks. A majority of respondents (74.0%) use multimodal analgesics in addition to opioids.

Conclusion

There is no consensus regarding the optimal multimodal anesthetic and analgesic regimen for total joint arthroplasty among surveyed board-certified arthroplasty surgeon members of AAHKS. Understanding current practice patterns in anesthesia, analgesia, and opioid prescribing may serve as a platform for future work aimed at establishing best clinical practices of maximizing effective postoperative pain control and minimizing the risks associated with prescribing opioids.

Do Geographic Region, Medicaid Status, and Academic Affiliation Affect Access to Care Among Medicaid and Privately Insured Total Hip Arthroplasty Patients?

26-09-2019 – Adam M. Almaguer, Alan R. Hsu, Jeffrey M. Pearson, Haley M. McKissack, James R. Jones, Sameer M. Naranje, Ashish B. Shah

Journal Article

Background

Medicaid provides health coverage to those beneath the federal poverty line. The literature shows that patients with Medicaid experience barriers to scheduling initial and follow-up visits, although this has not been studied in patients undergoing total hip arthroplasty (THA). The purpose of this study is to assess whether insurance type, geographic location, Medicaid expansion, or academic affiliation affect access to evaluation for THA.

Methods

The American Academy of Orthopedic Surgeons directory was used to call a total of 100 practices. Five random private and 5 random academic medical facilities were called from each of 5 Medicaid-expanded and 5 non-expanded states representing different US geographic regions. Calls were made by an investigator requesting the earliest available appointment for their fictitious parent to be evaluated for a THA. Half of the calls were made with the investigator reporting private insurance of Blue Cross Blue Shield (BCBS), and half reporting Medicaid. Appointment success rate and average time to appointment were compared. Further comparisons were drawn among Medicaid-expanded vs non-expanded states, geographic regions, and private vs academic affiliation.

Results

Appointments were successful for 99 of 100 (99%) calls made with BCBS, and 72 of 100 (72%) with Medicaid (P < .001). Success rates were significantly higher for BCBS, regardless of academic vs private affiliation. In all geographic regions, appointment success rate was significantly lower with Medicaid than with BCBS (P ≤ .01). Average time to appointment was also significantly longer for Medicaid (26 days) than private (13 days) insurance (P = .020). In the Medicaid group, appointment success rate was significantly greater for academically affiliated practices compared to private practices (84.0% vs 60.0%, respectively; P = .008).

Conclusion

Patients with Medicaid seeking consultation for THA experience limits in access to evaluation for THA when compared to patients with private insurance, regardless of geographic region or affiliation of the practice.

Outpatient Total Hip Arthroplasty Performed at an Ambulatory Surgery Center vs Hospital Outpatient Setting: Complications, Revisions, and Readmissions

26-08-2019 – Robert A. Sershon, James F. McDonald, Henry Ho, Nitin Goyal, William G. Hamilton

Journal Article

Background

Outpatient total hip arthroplasty (THA) utilization continues to grow. Literature suggests outpatient THA may result in low rates of complications and readmission. There are no studies comparing safety profiles of THA performed at ambulatory surgery centers (ASC) vs hospital outpatient (HOP) settings.

Methods

Prospectively collected data were reviewed on all patients who underwent THA from 2013 to 2018. ASC and HOP subgroups were compared, investigating difference in demographics, comorbidities, American Society of Anesthesiologists subgroups, all complications, revisions, emergency department (ED) visits, and readmissions within the first 90 days of surgery. An additional subgroup analysis of patients younger than 65 years was performed.

Results

Two surgeons performed 3063 THAs during the study period, including 965 outpatient cases (ASC = 335; HOP = 630). Thirty-seven (3.8%) complications occurred within 90 days. No differences were found between groups for 90-day complication rates (ASC = 13, 3.9%; HOP = 24, 3.8%; P = .48), revision rates (ASC = 0, 0%; HOP = 2, .3%; P = .30), all-cause reoperation rates (ASC = 1, 0.3%; HOP = 5, 0.8%; P = .35), ED visits (ASC = 3, 0.9%; HOP = 2, 0.3%; P = .23), or readmission rates (ASC = 2, 0.6%; HOP = 9, 1.4%; P = .25).

Conclusion

THA can be safely performed in both ASC and HOP settings with low 90-day postoperative complication, revision, reoperation, ED visit, and readmission rates. Based on the populations studied, we identified no statistically significant differences in rates of complications between ASC and HOP groups.

Conversion Total Knee Arthroplasty is Associated with Increased Post-Acute Care Costs

25-07-2019 – Michael F. Yayac, Samantha L. Harrer, Gregory K. Deirmengian, Javad Parvizi, P. Maxwell Courtney

Journal Article

Background

Alternative payment models have been viewed as successfully decreasing costs following primary total knee arthroplasty (TKA) while maintaining quality. Concerns exist regarding access to care for patients who may utilize more resources in a bundled payment arrangement. The purpose of this study is to determine if patients undergoing conversion of prior surgery to TKA have increased costs compared to primary TKA patients.

Methods

Claims from Medicare and a single private insurer were queried for all primary TKA patients at our institution from 2015 to 2016. Ninety-day post-acute care costs were compared between primary and conversion TKA. Secondary endpoints included discharge disposition, complications, and readmissions. A multivariate regression analysis was performed to identify independent risk factors for increased post-acute care costs and short-term outcome metrics.

Results

Of 3999 primary TKA procedures, 948 patients (23%) underwent conversion TKA. Conversion TKA was associated with greater post-acute care costs in patients with commercial insurance ($4714 vs $3759, P = .034). Among Medicare beneficiaries, prior ligament reconstruction was associated with increased post-acute care costs ($1917 increase, P = .036), while prior fracture fixation approached statistical significance ($2402 increase, P = .055). Conversion TKA was an independent risk factor for readmissions (odds ratio 1.46, 95% confidence interval 1.00-2.17, P = .050), while patients with a prior open knee procedure had higher rates of complications (odds ratio 2.41, 95% confidence interval 1.004-5.778, P = .049).

Conclusion

Our data suggest that conversion from prior knee surgery to TKA is associated with increased 90-day post-acute care costs and resource utilization, particularly prior open procedures. Without appropriate risk adjustment in alternative payment models, surgeons may be financially deterred from providing quality arthroplasty care given the reduced net payment and surgical complexity of such cases.

Cost of Care for Patients With Pre-Existing Comorbidities Undergoing Total Joint Arthroplasty: A Retrospective Cohort Study Evaluating Disease-Specific Perioperative Care

10-08-2019 – Megan Fiasconaro, Lauren A. Wilson, Jashvant Poeran, Jiabin Liu, Nicole Zubizarreta, Janis Bekeris, Alejandro Gonzalez Della Valle, David Kim, Stavros G. Memtsoudis

Journal Article

Background

Investigations suggest a relationship between increased resource utilization with disease burden and advanced age. However, it remains unknown the degree increased resource utilization is associated with pre-existing conditions, before complications occur.

Methods

This retrospective study identified total hip/knee arthroplasty cases in the Premier Database from 2006 to 2016 (N = 1,613,744), with hospitalization cost as the primary outcome. With a variable combining the conditions and complication, generalized linear models measured associations between condition/complication interaction groups and hospitalization cost. Estimates of percent cost increase by variable were obtained.

Results

Across all conditions, an increase in cost ranging from 0.38% to 4.28% was found in the absence of a complication. The “Condition = No, Complication = Yes” group was associated with a range of 11.50%-12.40% increase in average hospitalization cost, and the range was 14.43%-30.85% for the “Condition = Yes, Complication = Yes” group.

Conclusion

We found that having a high-risk condition without a complication accounted only for a modest hospitalization cost increase.

Should the Pareto Principle Be Applied as a Cost Savings Method in Hip and Knee Arthroplasty?

27-08-2019 – Lisa Lovse, Stéphane Poitras, Johanna Dobransky, Adrian Huang, Paul E. Beaulé

Journal Article

Background

Understanding the most significant contributions to the cost of completing total hip arthroplasty (THA) and total knee arthroplasty (TKA) is essential to optimize costs and meet funding standards. The objectives of this study are to determine whether cost distribution of THA and TKA follows the Pareto Principle (80/20 rule) and factors predictive of costs that could be modified.

Methods

All inpatient, primary, elective, and unilateral THA and TKA patients from April 2008 to September 2017 were retrospectively reviewed. The Pareto Principle was tested by dividing patients into top 5% cost increments and calculating patient cost category ratio. Relationship between patient-related factors and acute care costs and relationship between cost categories and length of stay (LOS) were examined using multiple regression.

Results

The Pareto Principle does not apply for THA or TKA patients, with the top 20% of costly patients accounting for approximately 30% of total costs. LOS is the strongest independent driver of costs. Operating room services and supplies accounted for over 50% of total costs but with low variability (coefficient of variation < 0.25). Laboratory and allied health costs had high variability (coefficient of variation > 1.5), but their contribution to total costs was low (from 0.76% to 5.68%).

Conclusion

THA and TKA costs do not follow Pareto Principle, concluding that targeting top costly patients is not as effective as focusing on overall patient population. Efforts to decrease overall costs should focus on decreasing the LOS and improving operating room process efficiencies including human resources for supplies and instruments.

Optimization of Orthopedic Surgical Instrument Trays: Lean Principles to Reduce Fixed Operating Room Expenses

02-09-2019 – Kyle H. Cichos, Zane B. Hyde, Scott E. Mabry, Elie S. Ghanem, Eugene W. Brabston, Leslie W. Hayes, Gerald McGwin, Brent A. Ponce

Journal Article

Background

Optimization of surgical instrument trays improves efficiency and reduces cost. The purpose of this study is to assess the economic impact of optimizing orthopedic instrument trays at a tertiary medical center.

Methods

Twenty-three independent orthopedic surgical instrument trays at a single academic hospital were reviewed from 2017 to 2018. Using Lean methodology, surgeons agreed upon the fewest number of instruments needed for each of the procedure trays. Instrument usage counts, cleaning times, room turnover times, tray weight, holes in tray wrapping, wet trays, and time invested to optimize each tray were tracked. Cost savings were calculated. Student’s t-test was used to determine statistical significance, with P < .05 considered significant.

Results

The mean instrument usage before and after Lean optimization was 23.4% and 54.2% (P < .0001). By Lean methods, 433 of 792 instruments (55%) were removed from 11 unique instrument trays (102 total trays), resulting in a reduction of 3520 instruments. Total weight reduction was 574.3 pounds (22%), ranging from 2.1-16.2 pounds per tray. The number of trays with wrapping holes decreased from 13 to 1 (P < .0001). The process of examining and removing instruments took an average of 7 minutes 35 seconds per tray. The calculated total annual savings was $270,976 (20% overall cost reduction).

Conclusion

In addition to substantial cost savings, tray optimization decreases tray weights and cleaning times without negatively impacting turnover times. Lean methodology improves efficiency in instrument tray usage, and reduces hospital cost while encouraging surgeon and staff participation through continuous process improvement.

Level of Evidence

Economic Quality Improvement, Level III.

Social Media Enhancement: Expanding Our Reach and Engagement With Our Loyal Readership in a Big Way!

20-11-2019 – John J. Callaghan, Michael A. Mont, Viktor E. Krebs, J. Bohannon Mason, David J. Backstein, James A. Browne, Michael J. Taunton, Chad A. Krueger

Editorial

Erratum to ‘Hemiarthroplasty Versus Total Hip Arthroplasty for the Management of Displaced Neck of Femur Fractures: A Systematic Review and Meta-Analysis’ The Journal of Arthroplasty 34 (2019) 1837–1843

29-09-2019 – Daniel P. Lewis, Daniel Wæver, Rikke Thorninger, William J. Donnelly

Published Erratum

Undetectable Hepatitis C Viral Load Is Associated With Improved Outcomes Following Total Joint Arthroplasty

29-07-2019 – David Novikov, James E. Feng, Afshin A. Anoushiravani, Jonathan M. Vigdorchik, Claudette M. Lajam, Thorsten M. Seyler, Ran Schwarzkopf

Journal Article

Background

Previous reports establish that infection with hepatitis C virus (HCV) predisposes total joint arthroplasty (TJA) recipients to poor postoperative outcomes. The purpose of the present study is to assess whether variation in HCV VL influences perioperative outcomes following TJA.

Methods

A multicenter retrospective review of all patients diagnosed with HCV who underwent primary TJA between January 2005 and April 2018 was conducted. Patients were stratified into 2 cohorts: (1) patients with an undetectable VL (U-VL) and (2) patients with a detectable VL (D-VL). Kaplan-Meier survivorship analysis was calculated with revision TJA as the end point. Subanalysis on the VL profile was done.

Results

A total of 289 TJAs were included (U-VL:118 TJAs; D-VL:171 TJAs). Patients in the D-VL cohort had longer operative times (133.9 vs 109.2 minutes), higher intraoperative blood loss (298.4 vs 219.5 m
L), longer inpatient hospital stays (4.0 vs 2.9 days), more postoperative infections (11.7% vs 4.2%), and an increased risk for revision TJA (12.9% vs 5.1%). Kaplan-Meier demonstrated that the U-VL cohort trended toward better survivorship (P = .17). On subanalysis of low and high VL, no difference in outcomes was appreciated.

Conclusion

TJA recipients with a detectable HCV VL have longer operative times, experience more intraoperative blood loss, have longer hospital length of stay, and are more likely to experience infection and require revision TJA. The blood loss, hospital length of stay, and revision rate findings should be interpreted with caution, however, as there are confounding factors. Our findings suggest that HCV VL is a modifiable risk factor that, can reduce the risk of infection and revision surgery. Additionally, serum HCV VL was not correlated with outcomes.

Corrigendum to ‘Patterns and Costs of 90-Day Readmission for Surgical and Medical Complications Following Total Hip and Knee Arthroplasty’ The Journal of Arthroplasty 34 (2019) 2304–2307

02-12-2019 – Ran Schwarzkopf, Omar A. Behery, HuiHui Yu, Lisa G. Suter, Li Li, Leora I. Horwitz

Published Erratum

Corrigendum to ‘Surgical Approaches and Hemiarthroplasty Outcomes for Femoral Neck Fractures: A Meta-Analysis’ The Journal of Arthroplasty 33 (2018) 1617-1627

25-11-2019 – Max P.L. van der Sijp, Danny van Delft, Pieta Krijnen, Arthur H.P. Niggebrugge, Inger B. Schipper

Published Erratum

Does Trochanteric Osteotomy Length Affect the Amount of Proximal Trochanteric Migration During Revision Total Hip Arthroplasty?

30-07-2019 – Sebastián A. León, Xin Y. Mei, Ethan B. Sanders, Oleg A. Safir, Allan E. Gross, Paul R.T. Kuzyk

Journal Article

Background

Nonunion and proximal trochanteric migration is a known complication of trochanteric osteotomy. This study examines the effect of osteotomy length on proximal greater trochanter (GT) migration.

Methods

We analyzed 113 modified trochanteric slide osteotomies and 73 extended trochanteric osteotomies performed between 2008 and 2016. All osteotomies were fixed using cerclage wires and had minimum 6-month radiographic follow-up. Spearman correlations were used to assess association between osteotomy length and GT migration distance. Chi-squared test and logistic regression were used to assess association between patient and surgical factors and GT migration >1 cm. Receiver operating characteristic curves were constructed to determine the optimal cutoff osteotomy length for predicting GT migration >1cm.

Results

Mean osteotomy length was 6.1 cm (range 3-12) for modified trochanteric slide osteotomies and 14.8 cm (range 8-23) for extended trochanteric osteotomies. Osteotomy length was negatively correlated (r = −0.340, P < .001) with GT migration distance. Longer osteotomy length was protective against GT migration >1 cm (odds ratio 0.67, P = .002). Receiver operating characteristic curve analysis demonstrated an optimal cutoff osteotomy length of 9.8 cm for predicting GT migration >1 cm (sensitivity 0.971, specificity 0.461). Among osteotomies <10 cm, those fixed using at least one distal wire below the lesser trochanter and vastus ridge demonstrated less mean GT migration (3.86 vs 7.12 mm, P = .009) and higher mean union rate (68.8% vs 31.2%, P < .001).

Conclusion

Osteotomies shorter than 10 cm are at higher risk of developing proximal GT migration >1 cm. A distal cerclage wire below the lesser trochanter and vastus ridge may help decrease the amount of GT migration.

Level of Evidence

Prognostic Level IV.

Effects of Sagittal Spinal Alignment on Postural Pelvic Mobility in Total Hip Arthroplasty Candidates

16-07-2019 – Aaron J. Buckland, Laviel Fernandez, Andrew J. Shimmin, Jonathan V. Bare, Stephen J. McMahon, Jonathan M. Vigdorchik

Journal Article

Background

Recent research has demonstrated that patients with reduced pelvic mobility from standing to sitting have higher rates of dislocation after total hip arthroplasty (THA). This study evaluates the effect of sagittal spinal deformity, defined by pelvic incidence–lumbar lordosis mismatch (PI-LL), on postural changes in pelvic tilt (PT).

Methods

A multicenter database of 1100 preoperative THA patients was queried. Anterior-pelvic-plane tilt (APPt), spinopelvic tilt (SPT), and LL were measured from radiographs of patients in supine, standing, flexed-seated, and stepping-up postures; PI was measured from computed tomography. Patients were separated into 3 groups based on PI-LL (<−10°, −10° to 10°, >10°) and propensity-score matched by PI. Lumbar flatback-deformity was defined as PI-LL > 10°, hyperlordosis: PI-LL < −10°. SPT/APPt, including changes between each posture were compared across PI-LL groups using analysis of variance, with post-hoc Tukey tests. Pearson correlations were reported when testing associations between SPT/APPt change and PI-LL.

Results

After propensity-score matching, 288 patients were analyzed (mean 65 y; 49% F). SPT and APPt change differed across all PI-LL categories from standing to seated, supine, and stepping-up with less SPT/APPt recruitment among hyperlordotic vs flatback patients (all P < .001). Greater PI-LL correlated with greater SPT recruitment from standing to seated (R = 0.294), supine (R = 0.292), and stepping-up (R = 0.207) (all P < .001). Smaller LL changes from standing to seated were associated with greater SPT recruitment (R = 0.372, P < .001).

Conclusions

Postural changes in SPT/APPt are associated with spinopelvic measures in THA candidates. Hyperlordotic patients tend to utilize their spines more compared with flatback patients who were more likely to recruit PT. Increased focus on patients with lumbar flatback and hyperlordosis may help in reducing prosthetic dislocation prevalence following THA.

Same-Day Surgery Does Not Increase the Manipulation Under Anesthesia and Reoperation Rates for Stiffness Following Bilateral Total Knee Arthroplasty

06-07-2019 – Lazaros A. Poultsides, Georgios K. Triantafyllopoulos, Florian Wanivenhaus, Matthias Pumberger, Stavros G. Memtsoudis, Thomas P. Sculco

Journal Article

Background

There is a paucity of data on the incidence of stiffness and need for subsequent manipulation under anesthesia (MUA) and reoperation following same-day bilateral total knee arthroplasty (BTKA). We compared the rates of at least 1 MUA, bilateral knee involvement, single and multiple MUA rates, and stiffness-related reoperation rates between patients undergoing same-day, same-admission staged, and staged within 1 year BTKA in a tertiary institution.

Methods

We analyzed institutional data for 3175 same-day (group A), 153 same-admission staged (group B), and 1226 staged within 1 year BTKA patients (group C) from 1998 to 2009. Several variables, including patient demographics, comorbidity profile, Charlson-Deyo index, and range of motion at different time points, were tabulated. Follow-up was minimum 1 year after first MUA. Univariate analyses were performed using the Wilcoxon rank-sum or Kruskal-Wallis test, and Fisher exact or the chi-square test for continuous and categorical variables, respectively. The Cochran-Armitage trend test was used to check the bilateral knee involvement rate across groups.

Results

Overall, 2.2% (98/4554) of BTKA patients required MUA. The rate of at least 1 MUA was similar across groups but the percentage of bilateral knee involvement was higher in group A. The single MUA rate was comparable among groups. Both no revision and revision reoperation rates were similar among the manipulated groups.

Conclusion

Same-day BTKA was not associated with increased incidence of single or multiple MUA and stiffness-related reoperation rates. These findings may facilitate preoperative counseling in patients with symptomatic bilateral knee disease, eligible for same-day BTKA.

Activity Impairment and Work Productivity Loss After Total Knee Arthroplasty: A Prospective Study

07-07-2019 – Tjerk H. Hylkema, Martin Stevens, Faith Selzer, Ben A. Amick, Jeffrey N. Katz, Sandra Brouwer

Journal Article

Background

Total knee arthroplasty (TKA) is increasingly performed among working-aged individuals, highlighting the importance of work-related outcomes. Therefore, the aim is to examine the extent of both activity impairment outside work and work productivity (absenteeism, presenteeism, at-work productivity loss) at 6 and 24 months post-TKA surgery. Additionally, associated risk factors with these outcomes were evaluated.

Methods

This analysis included 183 patients <70 years undergoing TKA who completed questionnaires pre-operatively and during follow-up. Outcomes were derived from the Work Productivity and Activity Impairment questionnaire and included activity impairment, absenteeism (sick leave), presenteeism (reduced work performance), and at-work productivity loss (overall work productivity loss). All outcomes were scaled 0%-100%, with higher percentages indicating higher impairments. Covariates included age, gender, education, pain catastrophizing, pain, function, psychological distress, and knee-related and health-related quality of life. Linear and logistic regression was used to assess associations between covariates and Work Productivity and Activity Impairment scores at follow-up.

Results

At 6 months, the mean activity impairment was 22.8% (standard deviation SD 23.5) dropping to 17.1% (23.1) by 24 months. Among workers, presenteeism was 18.4% (24.6) and at-work productivity loss was 20.8% (26.1). Both dropped significantly by 24 months to 14.2% (22.4) and 12.9% (20.9), respectively. Absenteeism levels were low at both time points. Pain catastrophizing was associated with all outcomes.

Conclusion

This study showed that activity impairment and work productivity loss are common following TKA, decreased significantly over time, but still existed 2 years post-operatively. Those reporting high levels of pain catastrophizing may benefit from targeted rehabilitation guidance to reduce and possibly prevent activity impairment and work productivity loss.

Incidence, Causes, and Timing of 30-Day Readmission Following Total Knee Arthroplasty

03-07-2019 – Gannon L. Curtis, Michael Jawad, Linsen T. Samuel, Jaiben George, Carlos A. Higuera-Rueda, Bryan E. Little, Hussein F. Darwiche

Journal Article

Background

It is important to study the incidence and causes of readmissions in order to understand why they occur and how to reduce them. This study looks at a national sample of patients following total knee arthroplasty (TKA) to identify incidences, trends, causes, and timing of 30-day readmissions.

Methods

Patients undergoing primary TKA from 2012 to 2016 in the American College of Surgeons National Surgical Quality Improvement Program database were identified (n = 197,192). Patients with fractures (n = 177), nonelective surgery (n = 2234), bilateral TKA (n = 5483), and cases with unknown readmission status (n = 1047) were excluded, leaving a total of 188,251 cases. Linear regression analysis was used to determine trends over time.

Results

The incidence of overall 30-day readmission following primary TKA from 2012 to 2016 was 3.19% (6014/188,251), with significant decreases in readmission rates during this time (β = −0.001, P < .001). The top 5 causes of readmission included superficial surgical site infection (SSI; 9.7%), non-SSI infection (9.5%), cardiovascular complications (CV; 9.3%), gastrointestinal complications (8.8%), and venous thromboembolisms (8.8%). The most common cause of readmission during postoperative week 1 was CV complications (12.2%), week 2 was superficial SSI (11.6%), week 3 was deep SSI (11.4%), and week 4 was deep SSI (12.4%).

Conclusion

Overall, 30-day readmissions following TKA were found to significantly decline from 2012 to 2016. The most common causes of overall readmission included superficial SSI, non-SSI infection, CV complications, gastrointestinal complications, and venous thromboembolisms. However, the most common causes of readmission changed from week to week postoperatively. This data may help institutions develop policies to prevent unplanned readmissions following TKA.

Clinical and Statistical Validation of a Probabilistic Prediction Tool of Total Knee Arthroplasty Outcome

03-07-2019 – Joshua G. Twiggs, Edgar A. Wakelin, Brett A. Fritsch, David W. Liu, Michael I. Solomon, David A. Parker, Antonio Klasan, Brad P. Miles

Journal Article

Background

Predicting patients at risk of a poor outcome would be useful in patient selection for total knee arthroplasty (TKA). Existing models to predict outcome have seen limited functional implementation. This study aims to validate a model and shared decision-making tool for both clinical utility and predictive accuracy.

Methods

A Bayesian belief network statistical model was developed using data from the Osteoarthritis Initiative. A consecutive series of consultations for osteoarthritis before and after introduction of the tool was used to evaluate the clinical impact of the tool. A data audit of postoperative outcomes of TKA patients exposed to the tool was used to evaluate the accuracy of predictions.

Results

The tool changed consultation outcomes and identified patients at risk of limited improvement. After introduction of the tool, patients booked for surgery reported worse Knee Osteoarthritis and Injury Outcome Score pain scores (difference, 15.2; P < .001) than those not booked, with no significant difference prior. There was a 27% chance of not improving if predicted at risk, and a 1.4% chance if predicted to improve. This gives a risk ratio of 19× (P < .001) for patients not improving if predicted at risk.

Conclusion

For a prediction tool to be clinically useful, it needs to provide a better understanding of the likely clinical outcome of an intervention than existed without its use when the clinical decisions are made. The tool presented here has the potential to direct patients to surgical or nonsurgical pathways on a patient-specific basis, ensuring patients who will benefit most from TKA surgery are selected.

Impact of Resilience on Outcomes of Total Knee Arthroplasty

07-07-2019 – Robert J. Magaldi, Ilene Staff, Ashly E. Stovall, Sherry A. Stohler, Courtland G. Lewis

Journal Article

Background

Resilience, defined as the ability to bounce back from stress, has been suggested as a predictor of surgical outcomes. The purpose of this study is to examine the relationship between resilience and patient-reported outcomes following primary elective total knee arthroplasty (TKA). We hypothesized that patients exhibiting greater preoperative resilience would report better outcome scores.

Methods

A prospective cohort of 153 patients (74 male, 79 female) undergoing primary elective TKA completed questionnaires preoperatively and at 3 and 12 months following their index procedure. The validated Brief Resilience Scale was used to evaluate resilience. Hierarchical multiple linear regression was used to analyze the effect of resilience on KOOS-JR (Knee Injury and Osteoarthritis Outcome Score JR) and PROMIS-10 (Patient-Reported Outcomes Measurement Information System) outcome scores.

Results

At 12 months, the change in the coefficient of determination (R2) attributable to preoperative resilience was 0.101 (P < .001) and 0.204 (P < .001) for physical and mental health, respectively. Although there was expected improvement in KOOS-JR scores following TKA, the effect of baseline resilience for this outcome was not significant. When evaluating resilience measured concurrently, there was significant correlation with both 3-month and 12-month KOOS-JR and PROMIS-10 outcome scores.

Conclusion

Preoperative resilience is a significant predictor of overall physical and mental health outcomes at both 3 and 12 months. Greater concurrent resilience predicted better scores across all outcomes. These findings suggest that major elective surgery, like other traumatic events, can cause a change in resilience. Although functional improvements after TKA are expected, those patients who exhibit greater resilience at baseline are more likely to report an improved quality of life.

The Combination of Inlay Patellofemoral Arthroplasty and Medial Unicompartmental Knee Arthroplasty Versus Total Knee Arthroplasty for Mediopatellofemoral Osteoarthritis: A Comparison of Mid-Term Outcomes

20-07-2019 – Enes Uluyardimci, Cetin Isik, Mesut Tahta, Fahri Emre, Sahin Cepni, Ismail Oltulu

Journal Article

Background

To the best of our knowledge, there have been no studies in the literature related to the use of second-generation inlay patellofemoral arthroplasty and unicompartmental knee arthroplasty combination (inlay PFA/UKA) in the treatment of mediopatellofemoral osteoarthritis (MPFOA). The aim of this study is to evaluate the efficacy of inlay PFA/UKA in MPFOA.

Methods

The study included 49 patients applied with inlay PFA/UKA because of MPFOA and 49 patients applied with TKA, matched one-to-one according to age, gender, body mass index, follow-up period, preoperative Knee Society Score, and range of motion. All the patients were evaluated clinically using the Knee Society Score, Knee Injury Osteoarthritis Outcome Score, and range of motion, and were also evaluated radiologically. Complication rates and length of hospital stay were compared.

Results

The mean follow-up period was 54 ± 4 and 54.4 ± 3.9 months in inlay PFA/UKA and TKA groups, respectively. (P = .841). No statistically significant difference was determined between the 2 groups in respect of the mean clinical scores at the final follow-up examination (P ≥ .129). Total complications were fewer and length of hospital stay was shorter in the inlay PFA/UKA group than in the TKA group (P = .037 and P = .002). There was no radiographic evidence of progression of lateral compartment osteoarthritis according to Kellgren-Lawrence in any patient in the inlay PFA/UKA group.

Conclusion

In selected patient groups, inlay PFA/UKA is an alternative to TKA, with lower complication rates, shorter length of hospital stay, and clinical and functional results similar to those of TKA without osteoarthritis progression in the unresurfaced lateral compartment in the mid-term.

Level of Evidence

III.

Adequate Positioning of the Tibial Component Is Key to Avoiding Bearing Impingement in Oxford Unicompartmental Knee Arthroplasty

27-06-2019 – Tomoyuki Kamenaga, Takafumi Hiranaka, Koji Takayama, Masanori Tsubosaka, Ryosuke Kuroda, Tomoyuki Matsumoto

Journal Article

Background

Bearing dislocation is a serious complication of unicompartmental knee arthroplasty (UKA) with the Oxford knee prosthesis equipped with a mobile bearing. We aimed to clarify the extent of intraoperative movement of the mobile bearing and its relationship with the positioning of prosthesis components in patients undergoing Oxford UKA.

Methods

This retrospective study included 50 patients (50 knees) who underwent Oxford UKA for anteromedial osteoarthritis or osteonecrosis of the knee. Intraoperative bearing movement was assessed at various angles of knee flexion (0°, 30°, 60°, 90°, and 120°). We stratified patients according to the extent of bearing movement posteriorly during intraoperative knee flexion, with or without contacting the lateral wall of the tibial component (with contact, 20 knees; without contact, 30 knees). Postoperative radiographic evaluations were conducted at 1 week postoperatively to assess the positional parameters of the tibial and femoral components (varus/valgus alignment, rotation, mediolateral position). Clinical evaluations were conducted at 1 year postoperatively (maximum flexion angle, Oxford Knee Score).

Results

Abnormal intraoperative movement of the mobile bearing resulting in contact with the lateral wall of the tibial component was associated with a significantly more medial position and external rotation of the tibial component, as well as poorer improvement in knee flexion angle at 1 year postoperatively.

Conclusion

In Oxford UKA recipients, the bearing may impinge on the lateral wall of the tibial component during flexion above 60° if the tibial component is placed too medially or exhibits pronounced external rotation, which may limit knee function improvement postoperatively.

Preoperative C-Reactive Protein/Albumin Ratio, a Risk Factor for Postoperative Delirium in Elderly Patients After Total Joint Arthroplasty

22-07-2019 – Jie Peng, Guorong Wu, Junping Chen, Hui Chen

Journal Article

Background

Postoperative delirium (POD), as an acute brain failure, is widely reported as a very common postoperative complication, and it is closely associated with increased morbidity and mortality. This study aimed to investigate potential risk factors including C-reactive protein/albumin ratio (CAR) for POD in elderly subjects after total joint arthroplasty (TJA).

Methods

A total of 272 elderly patients (aged 65∼85 years) who were scheduled to undergo elective TJA with epidural anesthesia were consecutively recruited. The data of baseline characteristics, operation-associated indexes, and preoperative laboratory tests were collected. POD assessment was performed daily within postoperative 7 days. Receiver operating characteristic curve analysis was utilized for evaluating the predictive and cut-off value of CAR for POD. Risk factors for POD were evaluated by the binary univariate and multivariate logistic regression analyses.

Results

Within postoperative 7 days, there were 55 patients who had suffered POD with an incidence of 20.2% (55/272). The area under the curve of CAR for POD was 0.804, with the cut-off value of 2.35, a sensitivity of 66.82%, and a specificity of 80.00%, respectively (95% confidence interval CI: 0.737-0.872, P < .001). Age (odds ratio: 2.02, 95% CI: 1.03-3.96, P = .038) and preoperative CAR level (odds ratio: 3.04, 95% CI: 1.23-7.23, P = .016) were 2 independent risk factors for POD in elderly subjects undergoing TJA.

Conclusions

Preoperative CAR level may be a promising predictor for POD in elderly subjects following TJA.

The Role of Malnutrition in Ninety-Day Outcomes After Total Joint Arthroplasty

27-06-2019 – Collin S. Black, Daniel E. Goltz, Sean P. Ryan, Amanda N. Fletcher, Samuel S. Wellman, Michael P. Bolognesi, Thorsten M. Seyler

Journal Article

Background

Research has linked malnutrition to more complications in total joint arthroplasty (TJA) patients. The role of preoperative albumin in predicting length of stay (LOS) and 90-day outcomes remains understudied. Often, an albumin cut-off ≤3.5 g/d
L is used as proxy for malnutrition, although this value remains understudied. This preoperative level may be missing some patients at risk for adverse events post TJA.

Methods

TJA patients at a single institution from 2013 to 2018 were reviewed for preoperative albumin level. In total, 4047 cases (total knee arthroplasty: 2058; total hip arthroplasty: 1989) had available data, including 90-day readmissions, 90-day emergency department (ED) visits, and postoperative LOS.

Results

About 5.6% experienced a readmission and 9.6% had at least one ED visit within 90 days. Overall prevalence of malnutrition was 3.6%, and this cohort experienced a longer average LOS (3.5 vs 2.2 days, P < .0001) and was more likely to experience a readmission (16% vs 5%, P < .0001) or ED visit (18% vs 9%, P = .0005). Additionally, albumin ≤3.5 g/d
L was correlated with more frequent discharge to skilled nursing facility/rehab (30.8% vs 14.7%, P < .0001), increased risk for 90-day readmission with univariable (odds ratio OR 1.79, P < .0001) and multivariable logistic regression (OR 1.55, P < .0001), and increased risk for 90-day ED visits with univariable (OR 1.62, P < .0001) and multivariable regression (OR 1.35, P < .0001). The optimal albumin cut-off was 3.94 g/d
L in a univariable model for 90-day readmission.

Conclusion

Screening for malnutrition may serve a role in preoperative evaluation. An albumin cutoff value of 3.5 g/d
L may miss some at-risk patients.

Discharge Home is Associated With Decreased Early Complications Following Primary Total Joint Arthroplasty

30-07-2019 – Michael A. Mayer, Kevin Pirruccio, Matthew Sloan, Neil P. Sheth

Journal Article

Background

Primary total hip (THA) and total knee arthroplasty (TKA) volume has increased over the past decade. Patients discharged home (HD) have demonstrated improved postoperative outcomes compared with non-home discharge (NHD) patients. We reviewed trends in HD over the past decade and compared complication rates between HD and NHD primary total joint arthroplasty (TJA) patients.

Methods

Retrospective analysis of the National Surgical Quality Improvement Program was performed on TJA cases and patients were grouped by discharge type. Trends in the prevalence of HD were compared by chi-square test, from 2011 to 2016. Univariate and bivariate statistics were performed. Multivariate logistic and propensity score–matched analyses were used to control for confounding variables.

Results

During the 6-year review, HD increased significantly for THA (71.2% to 83.6%) and TKA (65.6% to 80.7%). Overall HD was 75.4% of THA and 71.0% of TKA patients. Propensity matching identified 16,580 THA pairs and 34,952 TKA pairs. Compared with NHD patients, HD patients had shorter operative times, were younger, and had shorter lengths of stay. Controlling for confounders, the HD patients had lower risk of death within 30 days, lower risk of major medical morbidity, decreased risk of reoperation, and decreased risk of readmission compared with NDH patients. Multivariate models demonstrated similar findings.

Conclusion

HD in both THA and TKA independently predicts decreased early (30-day) postoperative complications after controlling for confounding variables. Given the improved outcomes, we advocate for continued emphasis on HD rather than NHD when clinically appropriate.

Hospital Consumer Assessment of Healthcare Providers and Systems: Do Patient Demographics Affect Outcomes in Total Hip Arthroplasty?

04-07-2019 – Nima Eftekhary, James E. Feng, Afshin A. Anoushiravani, Ran Schwarzkopf, Jonathan M. Vigdorchik, William J. Long

Journal Article

Background

The Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) score is a nationally standardized measure of a patient’s hospital experience. This study aims to assess whether HCAHPS scores vary by demographic or surgical factors in patients undergoing primary total hip arthroplasty.

Methods

Patients who completed an HCAHPS survey after a primary total hip arthroplasty between October 2011 and November 2016 were included in this study. Patient demographics and surgical factors were evaluated for correlations with individual HCAHPS questions.

Results

One thousand three hundred eighty-three HCAHPS questionnaires were reviewed for this study. Patients with a submitted HCAHPS response had an average age of 63.83 ± 10.17 years. Gender distribution was biased toward females at 57.27% (792 females) versus 42.73% (591 males). The average body mass index (BMI) was 28.68 ± 5.86 kg/m2. Race distribution was predominantly Caucasian at 81.49% (1127 patients), followed by “unknown” at 8.60% (119 patients) and African-American at 8.46% (117 patients). Home discharge occurred for 93.06% (1287 patients) versus 6.94% for facility discharge (96 patients). Mean length of stay was 2.41 ± 1.17 days. Each 1-year increase in age was positively correlated with a 0.16% increase in top-box response rate (β = 0.0016 ± 0.0008; P < .05). Male gender was correlated with a 4.61% increase in top-box response rate when compared to female gender (β = 0.0461 ± 0.0118; P < .01). BMI was found to be correlated with a 0.20% increase in HCAHPS response rates for each 1 kg/m2 increase (β = 0.0020 ± 0.0010; P < .05). For each day increase in length of stay, HCAHPS top-box response rates decrease by 3.41% (β = −0.0341 ± 0.0051; P < .0001). Race, marital status, smoking status, insurance type, and discharge disposition were not found to be significantly correlated with HCAHPS top-box response rate (P > .05).

Conclusion

The HCAHPS quality measurement metric affects physician reimbursement and may be biased by a number of variables including sex, length of stay, and BMI, rather than a true reflection of the quality of their hospital experience. Further research is warranted to determine whether HCAHPS scores are an appropriate measure of the quality of care received.