Journal of Arthroplasty

Risk Factors for Greater Than 24-Hour Length of Stay After Primary Total Knee Arthroplasty

24-11-2019 – Daniel J. Johnson, Joshua P. Castle, Matthew J. Hartwell, Albert M. DHeurle, David W. Manning

Journal Article

Background

Recently, the Center for Medicare Services removed total knee arthroplasty (TKA) from the inpatient-only procedure list. The purpose of this study is to assess the role of demographics, medical comorbidities, and postsurgical complications in predicting safe discharge to home within 24 hours after TKA.

Methods

Patients undergoing primary TKA between 2011 and 2016 were identified in the American College of Surgeons National Surgical Quality Improvement Program. Patients were grouped into those whose length of stay (LOS) was less than 24 hours after surgery vs those greater than 24 hours. Demographics, preoperative comorbidities, operative variables, and postoperative adverse events were studied as risk factors for LOS greater than 24 hours.

Results

A total of 210,075 patients undergoing primary TKA met the inclusion criteria, and of those, 18,134 (8.6%) patients were discharged within 24 hours postoperatively. In a risk-adjusted multivariate analysis, patients with increasing age, obesity, preoperative comorbidities of smoking, diabetes, dyspnea, chronic obstructive pulmonary disease, hypertension, bleeding disorder, corticosteroid use preoperatively, and dependent functional status conferred a greater risk for discharge greater than 24 hours. Male gender, spinal anesthesia, and monitored anesthesia care were protective against LOS greater than 24 hours.

Conclusion

This study suggests that dependent functional status, preoperative comorbidities, and postoperative complications are all associated with a LOS greater than 24 hours after TKA. Surgeons and patients should be aware of the clinical and demographic variables associated with risk for LOS greater than 24 hours when considering outpatient status for patients undergoing TKA.

Response to Letter to the Editor on “A Meta-Analysis of Outcomes in Total Hip Arthroplasty Recipients Following Pelvic Irradiation”

25-12-2019 – David Novikov, Dorian A. Cohen, David R. Swanson, Saman Vojdani, Fazel A. Khan

Letter

Letter to the Editor on “A Meta-Analysis of Outcomes in Total Hip Arthroplasty Recipients Following Pelvic Irradiation”

14-10-2019 – Alexander B. Christ, John H. Healey, Nicola Fabbri

Letter

Response to Letter to the Editor on “Non-Operative Management of Hip Labral Tears Yields Similar THA Conversion Rate to Arthroscopic Treatment”

13-12-2019 – Bryan L. Scott, Cody Lee, Aravind Athiviraham

Letter

Letter to the Editor on “Non-Operative Management of Hip Labral Tears Yields Similar THA Conversion Rate to Arthroscopic Treatment”

10-12-2019 – Jiangen Lian, Junfeng Lian, Mingjin Zhong

Letter

Response to Letter to the Editor on “Do Antibiotic Intramedullary Dowels Assist in Eradicating Infection in Two-Stage Resection for Septic Total Knee Arthroplasty?”

04-01-2020 – Matthew R. Zielinski, Mary Ziemba-Davis, Lucian C. Warth, Brian J. Keyes, R. Michael Meneghini

Letter

Letter to the Editor on “Do Antibiotic Intramedullary Dowels Assist in Eradicating Infection in Two-Stage Resection for Septic Total Knee Arthroplasty?”

31-12-2019 – Julien Chapleau, Kwan J. Park, Stephen J. Incavo

Letter

Response to Letter to the Editor on “Total Knee Arthroplasty Has Positive Effect on Patients With Low Mental Health Scores”

02-12-2019 – Patrick K. Horst, Andrew A. Barrett, James I. Huddleston, William J. Maloney, Stuart B. Goodman, Derek F. Amanatullah

Letter

Letter to the Editor on “Total Knee Arthroplasty Has Positive Effect on Patients With Low Mental Health Scores”

24-11-2019 – Fatih Özden

Letter

Response to Letter to the Editor on “The Role of Malnutrition in Ninety-Day Outcomes After Total Joint Arthroplasty”

21-12-2019 – Collin S. Black, Sean P. Ryan, Daniel E. Goltz, Amanda N. Fletcher, Samuel S. Wellman, Michael P. Bolognesi, Thorsten M. Seyler

Letter

Letter to the Editor on “The Role of Malnutrition in Ninety-Day Outcomes After Total Joint Arthroplasty”

17-12-2019 – Xiang-Dong Wu, Di Wu, Yong Liu, Wei Huang

Letter

Systematic Review of Modular Bicompartmental Knee Arthroplasty for Medio-Patellofemoral Osteoarthritis

05-11-2019 – Priyadarshi Amit, Nishant Singh, Ashish Soni, Nicholas K. Bowman, Michelle Maden

Journal Article

Background

We aimed to locate, appraise, and synthesize the available literature to assess the functional outcome of modular bicompartmental knee arthroplasty (BKA) compared to total knee arthroplasty (TKA) for medio-patellofemoral osteoarthritis.

Methods

After an extensive literature search based on electronic databases such as MEDLINE, EMBASE, CINAHL, and PubMed, and grey literature, 9 articles satisfied our selection criteria which included 1 randomized controlled trial, 1 prospective cohort, 3 retrospective cohort, and 4 case series. Narrative synthesis was performed due to clinical, methodological, and statistical heterogeneity among the included studies.

Results

There were 331 participants (341 knees) in this systematic review. BKA group included 229 patients (239 knees) and TKA group included 102 patients (102 knees). The quality of included studies ranged from moderate to very low as per GRADE (grading of recommendations, assessment, development, and evaluation working group) score with low to high risk of bias. Most of the studies showed comparable functional outcome in BKA compared to TKA such as Knee Society Score, Knee Osteoarthritis and Outcome Score, Short Form-36 score, and revision surgery in short-term to midterm follow-up. BKA patients achieved better range of movement and forgotten knee status than TKA patients. It resulted in longer operative time, but less intraoperative blood loss. Long-term series showed 95.1% survivorship of BKA at 5 years and 58% at 17 years.

Conclusion

Current evidence suggests that modular BKA provides comparable functional outcome to TKA at short-term to midterm follow-up, however, with poor long-term survivorship.

Low-Dose Aspirin Is Adequate for Venous Thromboembolism Prevention Following Total Joint Arthroplasty: A Systematic Review

18-11-2019 – Ibrahim Azboy, Hannah Groff, Karan Goswami, Mohammed Vahedian, Javad Parvizi

Journal Article

Background

Patients undergoing total joint arthroplasty (TJA) are at risk of developing venous thromboembolism (VTE) without adequate prophylaxis. Since the American Academy of Orthopedic Surgeons issued guidelines in 2007 recommending aspirin 325 mg bis in die for 6 weeks, aspirin has been favored as the main VTE prophylaxis. However, the appropriate dose and duration of aspirin are not well-studied. This systematic review aims to identify any differences between high and low dose as well as duration for aspirin thromboprophylaxis after TJA as outlined by previous studies.

Methods

A search was performed using Ovid MEDLINE, EMBASE, and PubMed, including articles up to July 2016. Studies were included if they contained at least 1 cohort that underwent TJA with aspirin as the sole chemoprophylaxis and reported either (1) symptomatic VTE or (2) secondary outcomes such as major bleeding or 90-day mortality.

Results

Forty-five papers were included. There were no significant differences in symptomatic pulmonary embolism, symptomatic deep vein thrombosis, 90-day mortality, or major bleeding between patients receiving low-dose or high-dose aspirin. Patients treated with aspirin for <4 weeks had a higher risk of major bleeding (1.59%) vs patients treated for 4 weeks (0.15%), which may be attributed to premature cessation or differential reporting. Patients treated with aspirin for <4 weeks had a statistically higher 90-day mortality (1.95%) vs patients treated for 4 weeks (0.07%). There was no significant difference between incidence of pulmonary embolism or deep vein thrombosis and the durations of aspirin treatment.

Conclusion

This review suggests that low-dose aspirin is not inferior to high-dose aspirin for VTE thromboprophylaxis in TJA patients. Additionally, patients treated with aspirin for less than 4 weeks may have a higher risk of major bleeding and 90-day mortality compared to patients treated for a longer duration.

Current Preclinical Testing of New Hip Arthroplasty Technologies Does Not Reflect Real-World Loadings: Capturing Patient-Specific and Activity-Related Variation in Hip Contact Forces

09-11-2019 – David E. Lunn, Enrico De Pieri, Graham J. Chapman, Morten E. Lund, Anthony C. Redmond, Stephen J. Ferguson

Journal Article

Background

Total hip arthroplasty (THA) implants are routinely tested for their tribological performance through regulatory preclinical wear testing (eg, ISO-14242). The standardized loading conditions defined in these tests consist of simplified waveforms, which do not specifically represent in vivo loads in different groups of patients. The aim of this study is to investigate, through musculoskeletal modeling, patient-specific and activity-related variation in hip contact forces (HCFs) in a large cohort of THA patients during common activities of daily living (ADLs).

Methods

A total of 132 THA patients participated in a motion-capture analysis while performing different ADLs, including walk, fast walk, stair ascent, and descent (locomotor); sit to stand, stand to sit, squat, and lunge (nonlocomotor). HCFs were then calculated using the Any
Body Modeling System and qualitatively compared across all activities. The influence of gender on HCFs was analyzed through statistical parametric mapping analysis.

Results

Systematic differences were found in HCF magnitudes and individual components in both locomotor and nonlocomotor ADLs. The qualitative analysis of the ADLs revealed a large range and a large variability in forces experienced at the hip during different activities. Significant differences in the 3-dimensional loading patterns were observed between males and females across most activities.

Conclusion

THA patients present a large variability in the forces experienced at the hip joint during their daily life. The interpatient variation might partially explain the heterogeneity observed in implant survival rates. A more extensive preclinical implant testing standard under clinically relevant loading conditions has been advocated to better predict and avoid clinical wear problems.

How Flat Is the Tibial Osteotomy in Total Knee Arthroplasty?

07-11-2019 – Luis E. Delgadillo, Hugh L. Jones, Sabir K. Ismaily, Shuyang Han, Philip C. Noble

Journal Article

Background

Cementless total knee arthroplasty has been developed to decrease the incidence of failure in younger and more active patients. However, failures are still more common in cementless versus cemented components. It is hypothesized that this is triggered by incomplete bone-tray contact. The present study compares the final contact area of a cementless tray as a function of the initial osteotomy flatness.

Methods

Eight surgeons prepared 14 cadaveric knees for cementless total knee replacement using standard instrumentation. The topography of each osteotomy was captured with a laser scanner; 3-dimensional computer models of the surfaces were generated. After scanning each tibia, the surgeons implanted cementless tibial trays using a manual impactor. Each tibia was then dissected, embedded in mounting resin, and sectioned. The sectioned blocks were observed under stereomicroscopy to identify points of bone-tray contact which were incorporated into the 3-dimensional models. Maps were then generated illustrating depicting contacting and noncontacting areas.

Results

The mean initial flatness of all specimens was 1.1 ± 0.35 mm. After impaction, 79.4% ± 0.3% of the surface had established bony contact. Of the noncontacting areas, 17.6% were within 0.3 mm of the tray. Only 2.6% of the surface was at distances reported to impede ingrowth. Noncontacting areas were typically located centrally. A trend in decreasing percent contact area with increased flatness tolerance was observed (R2 = 0.605).

Conclusion

(1) There is an inverse correlation between the flatness of the tibial osteotomy and the percentage of the bony surface in contact with underside of the tibial tray. (2) Almost all tray-tibia contact is generated during implantation through flattening of elevated features on the tibial surface. (3) Gaps between the tray and the tibia are consistently located in the central regions of the osteotomy proximal to the medullary canal.

Does the Effectiveness and Mechanical Strength of Kanamycin-Loaded Bone Cement in Musculoskeletal Tuberculosis Compare to Vancomycin-Loaded Bone Cement

12-11-2019 – Jae Hoo Lee, Sung Jae Shin, Sang-Nae Cho, Seung-Hun Baek, Do Hyun Kim, Kwan Kyu Park

Journal Article

Background

Antibiotic-loaded bone cement (ALBC) is used to deliver antimycobacterial agents into the focal lesion of musculoskeletal tuberculosis. Although kanamycin is currently used as an antimycobacterial agent for the treatment of multidrug-resistant tuberculosis, there is no information about its suitability in ALBC.

Methods

An in vitro experiment was conducted with cylindrical shape of 40 g of bone cement with 1, 2, and 3 g of kanamycin. Eluate (1 m
L) was extracted from each specimen to measure the level of elution and antimycobacterial activity on days 1, 4, 7, 14, and 30. The quantity of kanamycin in eluates was evaluated by a liquid chromatography-mass spectrometry system, and the antimycobacterial activity of eluates against Mycobacterium tuberculosis H37Rv was calculated by comparing the minimal inhibitory concentration. The ultimate compression strength was conducted using a material testing system machine (Instron 3366; Instron, Norwood, MA) before and after elution.

Results

Eluates from ALBC containing 2 and 3 g of kanamycin had effective antimycobacterial activity for 30 days, whereas eluates from ALBC containing 1 g of kanamycin were partially active until day 30. The pre-eluted compression strength of kanamycin-loaded cement and vancomycin-loaded cement was weaker as they contained a larger amount of antibiotics. There was no statistical difference between the strength of all kanamycin regimens and 1 g of vancomycin in the ultimate compression test. After 30 days of elution, the strength of all kanamycin-loaded cement and vancomycin-loaded cement cylinders was significantly lower than that of initial specimens (P < .05).

Conclusion

The antimycobacterial activity of ALBC containing more than 2 g of kanamycin was effective during a 30-day period. The ultimate compression strength of bone cement loaded with 1-3 g of kanamycin was comparable with 1 g of vancomycin while maintaining effective elution until day 30.

Mid-Term Survivorship of a Novel Constrained Acetabular Device

02-11-2019 – David A. Crawford, Joanne B. Adams, Kenneth W. Brown, Michael J. Morris, Keith R. Berend, Adolph V. Lombardi

Journal Article

Background

Recurrent instability after total hip arthroplasty is a difficult complication. In certain cases, a constrained acetabular device is needed to address these issues. The purpose of this study is to report the midterm outcomes and survivorship of a single novel constrained liner device.

Methods

A retrospective review as performed on all procedures (except first stage exchange for infection) in which a Freedom Constrained (Zimmer Biomet, Warsaw, IN) liner was used between December 2003 and November 2016. Patients with 2-year minimum follow-up or failure were included, yielding a cohort of 177 patients. Procedures were 130 aseptic revisions, 40 reimplantations following infection eradication, and 7 complex primaries. The constrained mechanism was implanted in 46 hips (26%) to treat active instability and 131 hips (74%) for increased risk of instability and intraoperative instability. Patients had on average 3.4 previous surgeries.

Results

With an average 7.1-year follow-up, 11 hips dislocated (6.2%), and 13 hips (7.3%) were revised for acetabular aseptic loosening, resulting in an overall constrained aseptic or mechanical failure rate of 13.6%. Nineteen hips (10.7%) failed from infection with 58% of these having had a previous infection. Patients with active instability had significantly higher failure for dislocation than patients who were at risk (15.2% vs 3%, P = .01). All-cause survival rate at 7 years was 74.8%, aseptic survival was 83.6%, and survival for instability was 91.8%.

Conclusion

Revision for instability remains challenging as many patients have had numerous previous surgeries and at-risk anatomy. Constrained inserts are one option to manage instability, but a high rate of recurrence can still occur.

Definitive Resection Arthroplasty of the Knee: A Surprisingly Viable Treatment to Manage Intractable Infection in Selected Patients

12-11-2019 – Ashton H. Goldman, Nicholas J. Clark, Michael J. Taunton, David G. Lewallen, Daniel J. Berry, Matthew P. Abdel

Journal Article

Background

Resection arthroplasty of the hip is considered a viable option after multiple failed attempts to eradicate a prosthetic joint infection (PJI). However, much less information about resection arthroplasty of the knee is available. The goals of this study were to determine the success of infection eradication with a resection arthroplasty of the knee and subsequent functional outcomes in this group.

Methods

We retrospectively identified 25 knees (23 patients) treated with resection arthroplasty of the knee for PJI performed at a single institution between 1974 and 2016. The mean age at resection arthroplasty was 65 years. The mean body mass index was 37 kg/m2, and the mean Charleston Comorbidity Index was 5. Patients had a mean of 5 operations on the knee (mean of 3 operations for infection) before the resection arthroplasty. Failure to eradicate the infection was defined as any reoperation for infection. Clinical outcomes were assessed via ambulatory status, use of gait aids, and ongoing pain. The mean follow-up was 4 years.

Results

At most recent follow-up, 84% (21 of 25) of knees were free of infection. Three patients had recurrent infection within the first year, and 1 patient had a late infection at 4 years postoperatively. However, only 1 patient required a subsequent amputation. Forty-five percent were community ambulators, 35% were household ambulators, and 20% were only able to transfer. All patients required knee bracing and assistive devices. Fifteen percent of patients were using long-term narcotics.

Conclusion

This large series demonstrates the results of selected use of resection arthroplasty as a treatment for recalcitrant periprosthetic knee infections that have failed multiple attempts to eradicate an ongoing PJI. The resection definitively solved the infection in 84% of patients. Functional results were variable but surprisingly good in some. All patients required bracing and assistive devices.

Treatment Outcomes and Attrition in Gram-Negative Periprosthetic Joint Infection

05-11-2019 – Irene L. Kalbian, Karan Goswami, Timothy L. Tan, Nathan John, Carol Foltz, Javad Parvizi, William V. Arnold

Journal Article

Background

While the prevailing belief is that periprosthetic joint infection (PJI) caused by Gram-negative (GN) organisms confers a poorer prognosis than Gram-positive (GP) cases, the current literature is sparse and inconsistent. The purpose of this study is to compare the treatment outcomes for GN PJI vs GP PJI and Gram-mixed (GM) PJI.

Methods

A retrospective review of 1189 PJI cases between 2007 and 2017 was performed using our institutional PJI database. Treatment failure defined by international consensus criteria was compared between PJI caused by GN organisms (n = 45), GP organisms (n = 663), and GM (n = 28) cases. Multivariate regression was used to predict time to failure.

Results

GM status, but not GN, had significantly higher rates of treatment failure compared to GP PJI (67.9% vs 33.2% failure; hazards ratio HR = 2.243, P = .004) in the multivariate analysis. In a subanalysis of only the 2-stage exchange procedures, both GN and GM cases were significantly less likely to reach reimplantation than GP cases (HR = .344, P < .0001; HR = .404, P = .013).

Conclusion

Although there was no observed difference in the overall international consensus failure rates between GN (31.1% failure) and GP (33.2%) PJI cases, there was significant attrition in the 2-stage exchange GN cohort, and these patients were significantly less likely to reach reimplantation. Our findings corroborate the prevailing notion that GN PJI is associated with poorer overall outcomes vs GP PJI. These data add to the current body of literature, which may currently underestimate the overall failure rates of GN PJI treated via 2-stage exchange and fail to identify pre-reimplantation morbidity.

Perioperative Chlorhexidine Gluconate Wash During Joint Arthroplasty Has Equivalent Periprosthetic Joint Infection Rates in Comparison to Betadine Wash

31-10-2019 – Adam Driesman, Michelle Shen, James E. Feng, Daniel Waren, James Slover, Joseph Bosco, Ran Schwarzkopf

Journal Article

Background

Dilute betadine wash has been used for the prevention of prosthetic joint infection (PJI). Appropriateness for this purpose has recently come into question as the Food and Drug Administration determined that several commercial products did not pass the standards of proper sterility. The goal of this study is to determine if change in our institution’s perioperative infection protocol to sterile chlorhexidine gluconate wash affected rates of PJI.

Methods

This is a retrospective study of prospectively collected data for patients who underwent unilateral primary total knee arthroplasty and total hip arthroplasty. Chart review was performed to determine 90-day and 1-year readmissions and the development of PJI as per the diagnostic criteria of the Musculoskeletal Infection Society.

Results

A total of 2386 consecutive patients were included in this study. There were no significant demographic differences between the 2 groups. There was no statistically significant difference in the rate of PJI requiring a return trip to the operating room between the 2 cohorts: 4 in chlorhexidine vs 7 in betadine at 3 months (P = .61); and 9 in chlorhexidine and 14 in betadine at 1 year (P = .48, respectively). There was also no difference in the rate of wound complications between the betadine and chlorhexidine use (P = .93).

Conclusion

When comparing patients who received a betadine wash intraoperatively to those who received a chlorhexidine gluconate wash, there were no statistically significant differences in the rate of postoperative PJIs or return trips to the operating room. Although chlorhexidine gluconate and betadine have equal efficacy in the prevention of PJI, betadine is a far less expensive alternative if their sterility concerns are unwarranted

Level of Evidence

Therapeutic Level III.

Tranexamic Acid Is Associated With Reduced Periprosthetic Joint Infection After Primary Total Joint Arthroplasty

15-11-2019 – Hamidreza Yazdi, Mitchell R. Klement, Mohammed Hammad, Daisuke Inoue, Chi Xu, Karan Goswami, Javad Parvizi

Journal Article

Background

Previous studies have demonstrated preoperative anemia to be a strong risk factor for periprosthetic joint infection (PJI) in total joint arthroplasty (TJA). Allogeneic blood transfusion can be associated with increased risk of PJI after primary and revision TJA. Tranexamic acid (TXA) is known to reduce blood loss and the need for allogeneic blood transfusion after TJA. The hypothesis of this study is that administration of intravenous TXA would result in a reduction in PJI after TJA.

Methods

An institutional database was utilized to identify 6340 patients undergoing primary TJA between January 1, 2013 and June 31, 2017 with a minimum of 1-year follow-up. Patients were divided into 2 groups based on whether they received intravenous TXA prior to TJA or not. Patients who developed PJI were identified. All PJI patients met the 2018 International Consensus Meeting definition for PJI. A multivariate regression analysis was performed to identify variables independently associated with PJI.

Results

Of the patients included, 3683 (58.1%) received TXA and 2657 (41.9%) did not. The overall incidence of preoperative anemia was 16%, postoperative blood transfusion 1.8%, and PJI 2.4%. Bivariate analysis showed that patients who received TXA were significantly at lower odds of infection. After adjusting for all confounding variables, multivariate regression analysis showed that TXA is associated with reduced PJI after primary TJA.

Conclusion

TXA can help reduce the rate of PJI after primary TJA. This protective effect is likely interlinked to reduction in blood loss, lower need for allogeneic blood transfusion, and issues related to immunomodulation associated with blood transfusion.

A Novel Adjunct Indicator of Periprosthetic Joint Infection: Platelet Count and Mean Platelet Volume

25-11-2019 – Taylor Paziuk, Alexander J. Rondon, Karan Goswami, Timothy L. Tan, Javad Parvizi

Journal Article

Background

Diagnosing a periprosthetic joint infection (PJI) is difficult and often requires a combination of objective findings. The purpose of this study is to determine whether platelets, a known acute phase reactant, would be able to further aid in the diagnosis of PJI.

Methods

A single-institution retrospective review study was performed on all revision total hip and knee arthroplasties done between 2000 and 2016 (n = 4939). PJI was defined by Musculoskeletal Infection Society criteria (n = 949). Platelet count and mean platelet volume were assessed from each patient’s preoperative complete blood count. These values were then assessed as a ratio via receiver operating characteristic (ROC) curve analysis.

Results

The platelet count to mean platelet volume ratio for PJI patients was 33.45 compared to 25.68 for patients in the aseptic revision cohort (P < .001). ROC curve analysis demonstrates that a ratio of 31.70 has a sensitivity of 48.10 (95% confidence interval 44.9-51.4) and a specificity of 80.85 (95% confidence interval 79.6-82.1). This specificity was higher than that of both estimated sedimentation ratio (ESR) and C-reactive protein (CRP) for the same cohorts using optimal values determined via ROC curve analysis. When used in conjunction with ESR and CRP, there was a statistically significant increase in the diagnostic performance of the model used to assess PJI relative to the model that just employed ESR and CRP (P < .05).

Conclusion

Our study demonstrates that platelets and their associated serum biomarkers are associated with PJI and warrant consideration in patients who are being evaluated for potential PJI.

Monoflanged Custom-Made Acetabular Components Promote Biomechanical Restoration of Severe Acetabular Bone Defects by Metallic Defect Reconstruction

19-11-2019 – Sebastian G. Walter, Thomas M. Randau, Nadine Gravius, Sascha Gravius, Frank S. Fröschen

Journal Article

Background

Custom-made acetabular components (CMAC) are one established method to address severe acetabular bone defects. Monoflanged CMAC may represent an advantageous alternative to establish triflanged CMAC as they promote better primary stability through metallic defect reconstruction and thus anatomic restoration of the center of rotation (COR).

Methods

Fifty-eight consecutive (21 triflanged and 37 monoflanged) CMAC were evaluated for overall survival, reasons for revision, radiological restoration of COR, and clinical outcome parameters.

Results

There were no significant differences between both design types regarding overall survival, revision rates, Harris Hip Score, or visual analog scale (pain) score at latest follow-up (mean, 56.3 ± 28.7 months). Triflanged CMAC showed a significant lateralization (P ≤ .001) and cranialization (P = .003) of the COR compared to the contralateral side. Monoflanged CMAC restored the anatomic COR. Reasons for revision surgery and explantation were periprosthetic joint infection (n = 12) and aseptic loosening (n = 2) without significant differences between both groups.

Conclusion

Monoflanged CMAC demonstrate similar clinical outcome parameters and survival rates as triflanged CMAC but superior biomechanical features and represent therefore a solid alternative treatment option and implant design.

Eighteen-Year Follow-Up Study of 2 Alternative Bearing Surfaces Used in Total Hip Arthroplasty in the Same Young Patients

02-11-2019 – Young-Hoo Kim, Jang-Won Park

Journal Article

Background

This study compares the long-term functional, radiographic, and computed tomography scan outcomes and implant survivorship of ceramic-on-ceramic total hip arthroplasty (C-O-C THA) and ceramic-on-highly cross-linked polyethylene total hip arthroplasty (C-O-HXLPE THA) in the same patients.

Methods

In this randomized, prospective trial conducted between January 1999 and April 2003, 133 patients (266 hips) younger than 55 years were enrolled. Each patient received C-O-C THA in 1 hip and a C-O-HXLPE THA in the other. The mean follow-up was 17.1 years (range, 15-18 years); there were 84 men and 49 women with a mean age of 53 ± 7 years (range, 25-55 years).

Results

At the latest follow-up, mean Harris hip scores (94 vs 93 points; P = .861), pain scores (43 vs 42 points; P = .651), and patient satisfaction scores (7.8 vs 7.6 points; P = .379) were not different between the 2 groups. Eight hips (3%) in the C-O-C THA had an audible squeaking sound. The mean annual penetration rate of HXLPE was 0.0162 ± 0.032 mm per year. No osteolysis was recorded on radiographs or computed tomography scans in either group. At 17.1 years, the survival rate of the acetabular component was 97% in the C-O-C bearing group and 98% in the C-O-HXLPE bearing group (P = .923). The survival rate of the femoral component was 99% in both groups.

Conclusion

Both C-O-C THA and C-O-HXLPE THA functioned well, with no osteolysis at mean of 17.1-year follow-up.

The Influence of Obesity on Hip Pain, Function, and Satisfaction 10 Years Following Total Hip Arthroplasty

02-11-2019 – Samantha J. Haebich, Peter Mark, Riaz J.K. Khan, Daniel P. Fick, Craig Brownlie, James A. Wimhurst

Journal Article

Background

The prevalence of obesity is rising, and increasing numbers of joint arthroplasty surgeries are being performed on obese patients. Concern exists that obesity increases surgical risk; however, its impact on function following total hip arthroplasty (THA) is inconsistently affirmed and less understood. A paucity exists in the literature pertaining long-term objective functional measures. Therefore, we investigated the impact of obesity on hip pain, function, and satisfaction 10 years following THA.

Methods

This single-center, prospective, observational study categorized consecutive THA patients according to their body mass index to nonobese (<30 kg/m2) and obese (≥30 kg/m2) groups. Preoperative assessment included a numerical pain rating and the Oxford Hip Score. These were repeated along with a 6-minute walk test and a Likert satisfaction scale at 3 months, 1, 5, and 10 years postoperatively.

Results

The series included 191 primary THA patients. No significant differences were found in hip pain or function between the obese and nonobese groups. Obese patients however had poorer walking capacity (P = .008), were more likely to use walking aids (P = .04), and were less satisfied (P = .04) at 10 years.

Conclusion

THA confers significant long-term symptom resolution irrespective of obesity; however, despite undergoing surgery, obese patients can be counseled they may not be as satisfied as or achieve the same walking capacity as nonobese individuals.

Midterm Outcomes and Frequency of Osteolysis of Total Hip Arthroplasty Using Cementless Modular Stem for Asian Patients

07-11-2019 – Atsuko Sato, Naoki Okuda, Sachiyuki Tsukada, Akimasa Kimura, Masanori Kase, Masaaki Matsubara

Journal Article

Background

Modular stems are useful for total hip arthroplasty (THA) in anatomically difficult dysplasia. Here, we present mean 6.8-year outcomes of cementless primary THA using S-ROM-A (modified modular stem for Asian patients) femoral prosthesis in anatomically difficult cases.

Methods

Charts of 373 patients (461 hips) undergoing THA (mean age, 58 years) were reviewed for clinical evaluation of modified Merle d’Aubigné-Postel score and Kaplan-Meier survivorship with revision for any reason as the end point. For radiographic analysis, 331 patients (412 hips) followed up for ≥5 years were included. Bearing couples were metal-on-metal (n = 145), metal-on-polyethylene (n = 120), and ceramic-on-polyethylene (n = 147). Radiography and multiplanar computed tomography were performed.

Results

No postoperative dislocation or deep infection occurred. Mean modified Merle d’Aubigné-Postel score improved significantly (10.9 points preoperatively, 16.7 points at last follow-up; P < .001). Cumulative 5- and 10-year stem survival rates were 100% and 84%, respectively (95% confidence interval, 75%-93%). All stems were classified as bone ingrown fixation. Osteolysis occurred in metal-on-metal (42.8%) and metal-on-polyethylene (15.8%) groups. Mean time to osteolysis was ~3 years, with no significant difference between 3 groups (P = .264). In logistic regression, lower cup inclination angle was significantly associated with osteolysis (odds ratio, 0.914; 95% confidence interval, 0.84-0.99; P = .029).

Conclusion

S-ROM-A femoral prosthesis achieved excellent midterm fixation, and the modular system was useful in primary THA with severe deformity. Bearing couples are potentially associated with adverse reactions to metal debris. S-ROM-A with ceramic-on-polyethylene bearing couples may be an option for anatomically difficult THA.

Highly Cross-Linked Polyethylene in Total Hip Arthroplasty in Patients Younger Than 50 Years With Osteonecrosis of the Femoral Head: A Minimum of 10 Years of Follow-Up

07-11-2019 – Byung-Woo Min, Chul-Hyun Cho, Eun-Suck Son, Kyung-Jae Lee, Si-Wook Lee, Kwang-Soon Song

Journal Article

Background

Polyethylene wear and subsequent periprosthetic osteolysis remain a major concern of total hip arthroplasty (THA) failure in young, active patients with osteonecrosis of the femoral head (ONFH). The literature is lacking regarding the long-term performance of highly cross-linked polyethylene (HXLPE) in these patients. The purpose of this study is to evaluate long-term results for cementless THA using metal-on-HXLPE bearing couplings in patients younger than 50 years with ONFH.

Methods

We retrospectively evaluated the clinical and radiographic results of a consecutive series of 85 THAs (in 67 patients) performed with HXLPE liners (Durasul) in patients younger than 50 years who had ONFH. All procedures were performed at a single institution by a single surgeon using the same type of implants. The minimum duration of follow-up was 10 years (mean, 13.5 years; range, 10-17.3 years). Wear was measured using computer software. Osteolysis was evaluated with the use of radiography and computed tomography.

Results

The mean Harris hip score was 49.3 points (range, 26-68 points) before surgery, which improved to 93.6 points (range, 87-98 points) after surgery. Neither femoral nor acetabular components displayed mechanical loosening, and no components had been revised by the final follow-up evaluation. Radiographs and computed tomography scans did not demonstrate osteolysis. The mean liner wear was 0.037 mm/y (range, 0-0.099 mm/y). With the data available, univariate regression analysis did not demonstrate that age, sex, weight, activity level, underlying cause of osteonecrosis, liner thickness, or cup inclination had any influence on liner penetration.

Conclusion

Although the long-term effects of HXLPE particles remain unknown, the implant survivorship rate and wear rate in our study are promising and support the continued use of metal-on-HXLPE bearing couplings in these high-risk patients because they do not produce any of the issues associated with hard-on-hard couplings.

Level of Evidence

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Perioperative Outcomes and Complications After Primary Total Hip Arthroplasty in Patients With Disproportionately Short Stature: A Matched Cohort Analysis

05-11-2019 – Hiba K. Anis, Kara M. McConaghy, Ryan J. Charles, Jared A. Warren, Daniel C. Santana, Alison K. Klika, Wael K. Barsoum, Viktor E. Krebs, Carlos A. Higuera, Nicolas S. Piuzzi

Journal Article

Background

This study compared (1) perioperative outcomes, (2) postoperative complications, and (3) reoperation rates after primary total hip arthroplasty (THA) between short stature patients and matched control patients.

Methods

A review of primary THA patients from 2012 to 2017 using an institutional database was conducted. This yielded 12,850 patients of which 108 were shorter than 148 cm. These patients were matched 1:1 by age (P = .527), gender (P = .664), and body mass index (P = .240) to controls. The final study population with minimum 1-year follow-up that was included for analysis comprised 47 patients in the short stature cohort and 57 patients in the control cohort. The following outcomes/complications were compared: operative times, lengths of stay (LOSs), intraoperative fractures, minor complications, 90-day readmissions, and revisions.

Results

Operative times were significantly longer in the short stature cohort than in the matched control cohort (133 ± 65 minutes vs 104 ± 30 minutes, P = .005). In addition, hospital LOS was slightly longer in the short stature group than in the matched control groups (3.2 ± 1.5 days vs 2.6 ± 1.0, P = .017). Rates of intraoperative fractures (P = 1.000), minor complications P = .406), 90-day readmissions (P = .5000), and revision (P = .202) were similar between the short stature and control cohorts.

Conclusion

Patients with disproportionately short stature had longer operative times and slight longer LOS. However, complication and readmission rates were similar. Future studies with larger sample sizes are warranted to confirm these findings and further evaluate implant survivorship in this unique THA patient population.

Complications and Readmission Incidence Following Total Hip Arthroplasty in Patients Who Have End-Stage Renal Failure

01-12-2019 – Jacob A. Malkani, Jamie C. Heimroth, Kevin L. Ong, Heather Wilson, Mathew Price, Nicolas S. Piuzzi, Michael A. Mont

Journal Article

Background

The number of patients who have end-stage renal disease undergoing primary total hip arthroplasty (THA) has increased over the past decade. The purpose of this study is to evaluate mortality, complications, and 90-day readmission incidences in patients who have end-stage renal disease undergoing THA.

Methods

Patients who had a primary THA between January 1, 2007, and December 31, 2016, were identified from the 5% Medicare database. A total of 55,297 THA patients were stratified into 3 groups: renal dialysis (without transplant), renal transplant, and those without such renal problems. Risk of readmissions, dislocations, periprosthetic joint infections (PJIs), venous thromboembolic diseases, and mortalities up to 5 years following primary THA was compared. Multivariate Cox regression analyses were used to evaluate the effect of patient and hospital characteristics on the adjusted complication risks.

Results

Mortalities at 5 years was 62.6% in the renal dialysis group, 37.3% in the renal transplant group, compared to 15.0% in the nonrenal group. Dislocations (7.6%) and PJIs (7%) were significantly higher in the dialysis group (P < .001). No significant differences in venous thromboembolic diseases (all timepoints) and revisions (all timepoints except at 90 days) between the renal groups were observed. The 90-day readmission risks were significantly greater in both the dialysis (55%) and transplant (43%) groups compared to the nonrenal cohort (30%) (P < .001).

Conclusion

Renal dialysis patients undergoing THA are at increased risk of PJIs (7%), dislocations (7.6%), revisions, and mortalities at 90 days compared to transplant and nonrenal patients. Both dialysis and transplant patients are high-risk groups with significantly increased 90-day readmission incidences of 55% and 43%, respectively, which makes their inclusion into a bundled payment model challenging.

Effects of Estimated Glomerular Filtration Rate on 30-Day Mortality and Postoperative Complications After Total Hip Arthroplasty: A Risk Stratification Instrument

20-12-2019 – Jared A. Warren, Jaiben George, Hiba K. Anis, Olivia K. Krebs, Robert M. Molloy, Carlos A. Higuera, Nicolas S. Piuzzi

Journal Article

Background

Chronic kidney disease (CKD) is a relatively common comorbidity that has been shown to adversely affect outcomes in total hip arthroplasty (THA), as well as to increase the procedures total costs. However, the effect of different stages of kidney disease and the association of estimated glomerular filtration rate (e
GFR) with perioperative THA complications are less understood. Therefore, the aims of this study were to investigate the relationships between e
GFR, both as a categorical and continuous variable and 30-day outcomes and complications.

Methods

The National Surgical Quality Improvement Program database was used to identify 101,925 primary THAs between January 1, 2008, and December 31, 2016. The following outcomes were assessed: 30-day mortality, 30-day major complications, 30-day minor complications, specific complications, and discharge disposition. To evaluate the effect of e
GFR status on outcomes and complication, multivariate regression models were created to adjust for differences in patient demographics and comorbidities. In addition, multivariate spline regressions were developed to assess the nonlinear relationships between e
GFR as a continuous variable and the outcomes of interest.

Results

Our study revealed that as e
GFR decreases to <30 m
L/min/1.73 m2, there is an increased risk for mortality and nonhome discharge (P < .05). There was an increased risk for any major complication and any minor complication as well as several specific medical complications such as transfusion and myocardial infarction (P < .05) for an e
GFR of <60 m
L/min/1.73 m2. Patients e
GFR had a nonlinear relationship with mortality (P = .0001), any major complication (P < .001), and any minor complication (P < .001), as well as a number of other specific medical complications. Once the e
GFR, <60 m
L/min/1.73 m2 the increase was exponential for mortality, major complications, and minor complications. For example, mortality increased of 900% for <15 m
L/min/1.73 m2 or on dialysis, 600% for 15 to 30 m
L/min/1.73 m2 and 50% for 30 to 60 m
L/min/1.73 m2. Similarly, nonlinear relationships were discovered between e
GFR and nonhome discharge (P < .001).

Conclusion

Patients with lower e
GFR, and in particular those with <30 m
L/min/1.73 m2, are more likely to sustain medical complications and have 6 to 9 times higher mortality than patients with normal e
GFR. THA patients with CKD should be appropriately counseled and advised on the risk of postoperative complications by using e
GFR as a screening tool.

Determining and Achieving Target Limb Length and Offset in Total Hip Arthroplasty Using Intraoperative Digital Radiography

09-11-2019 – Eytan M. Debbi, Sean S. Rajaee, Brian F. Mayeda, Brad L. Penenberg

Journal Article

Background

Achieving appropriate limb length and offset in total hip arthroplasty (THA) is challenging. Target limb length and offset may not always mean equal radiographic measurements bilaterally. The goal of this study is to introduce a method for determining as well as achieving target limb length and offset using digital radiographic measurements.

Methods

One hundred and two consecutive patients with unilateral hip osteoarthritis undergoing primary THA in the lateral decubitus position were included. Limb length and offset were measured on anterior-posterior pelvic radiographs preoperatively, intraoperatively, and postoperatively. Offset was defined as the length of a line parallel to the inter-teardrop line, extending from the edge of the ischium, at about the lower border of the ipsilateral obturator foramen, to the edge of the femoral cortex, usually at, or just below, the neck resection level. Target limb length was determined for each patient based on patient perception and severity of disease. Target offset equaled the contralateral limb. Using intraoperative digital radiography, adjustments were made until targets were achieved and the hip was stable. Patients were followed for an average of 4.2 years postoperatively.

Results

Limb length was within 5 mm of target measurements in 100% of patients and offset was within 5 mm of targets in 97.1%. Target measurements differed by >5 mm from the contralateral side in 2.0% of limb length and 2.9% of offset measurements. There were no significant differences between intraoperative and postoperative limb length (P = .261) or offset (P = .747) measurements. At final follow-up, there were no dislocations or reoperations and average Hip disability and Osteoarthritis Outcome Score for Joint Replacement was 95.78.

Conclusion

Target limb length and offset goals can be determined for most patients undergoing THA. Targets are not always equal to the contralateral side. Intraoperative digital radiography can allow surgeons to accurately achieve target limb length and offset to within 5 mm in a homogenous cohort of patients with unilateral hip osteoarthritis with excellent clinical outcomes.

Risk Factors for Periprosthetic Femur Fracture and Influence of Femoral Fixation Using the Mini-Anterolateral Approach in Primary Total Hip Arthroplasty

07-11-2019 – Carl L. Herndon, Jared A. Nowell, Nana O. Sarpong, H. John Cooper, Roshan P. Shah, Jeffrey A. Geller

Journal Article

Background

The mini-anterolateral (AL) approach for total hip arthroplasty (THA) has gained popularity. In contrast to other approaches, risk factors for periprosthetic femur fractures have not been well established for the AL approach.

Methods

Six hundred eighty-four primary THAs performed using the AL approach were retrospectively reviewed for risk factors associated with perioperative periprosthetic femur fractures within 3 months of surgery. Risk factors evaluated were gender, age, body mass index, laterality, and Dorr ratio of the proximal femur. Cemented stems and collared uncemented stems were compared to uncemented tapered-wedge and meta-diaphyseal stems. A Student’s t-test was used for continuous variables, and a chi-squared test was used for categorical variables.

Results

Of 684 primary THAs performed, 57 (8.3%) resulted in fracture. Twenty-eight (4.1%) occurred intraoperatively and 29 (4.2%) occurred postoperatively within 90 days. All intraoperative fractures were fixed at the time of surgery and healed uneventfully. Of the postoperative fractures, 15 (2.2%) were amenable to nonoperative management and healed. Fourteen (2.0%) required revision arthroplasty. There was a significantly lower rate of fracture in patients receiving cemented or collared stems (0%, n = 101) than in those receiving tapered-wedge or meta-diaphyseal fitting stems (9.8%, n = 583; P = .0009). Odds of fracture increased with female gender (P = .0063) and increasing Dorr ratio (P = .0003). Analysis showed a trend toward increased risk with older age, but did not achieve statistical significance. Body mass index and laterality showed no statistically significant effect.

Conclusion

Performing primary THA via the AL approach, 2.0% of patients had a postoperative fracture requiring revision within the first 3 months. With cemented and collared stems, the fracture rate was significantly lower. Surgeons should consider using cemented or collared stems in high-risk patients.

Prospective Evaluation of the Posterior Tissue Envelope and Anterior Capsule After Anterior Total Hip Arthroplasty

05-11-2019 – Alexander S. McLawhorn, Alexander B. Christ, Rachelle Morgenstern, Alissa J. Burge, Michael M. Alexiades, Edwin P. Su

Journal Article

Background

Femoral exposure for direct anterior approach (DAA) total hip arthroplasty (THA) invariably requires posterior soft tissue releases. Released posterior structures cannot be repaired. The purpose of this study is to describe the frequency and anatomic consequences of DAA THA posterior soft tissue releases and to compare the appearance of the anterior capsule between a group of patients who had capsulotomy and repair versus capsulectomy.

Methods

Thirty-two DAA THA patients underwent metal artifact reduction sequence magnetic resonance imaging at discharge and 1-year follow-up. Seventeen had underwent capsulotomy and repair and 15 capsulectomy. A radiologist blinded to intraoperative data scored each metal artifact reduction sequence magnetic resonance imaging. Anterior capsular integrity, status of the piriformis and conjoint tendons, and muscle atrophy were graded. Descriptive statistics were performed to analyze results.

Results

Immediately postoperatively, 75% of piriformis tendons were intact and 38% of conjoined tendons were intact. At 1 year, 97% had an intact piriformis and conjoined tendon, although many were in continuity through scar with the capsule. The posterior capsule directly contacted bone in all patients. At 1 year, none of the patients who underwent capsulotomy with repair had persistent anterior capsule defects, while 27% in the capsulectomy group had persistent defects.

Conclusion

Posterior capsule and conjoined tendon releases were commonly performed during DAA THA, yet continuity with bone was frequently achieved at 1 year. In this study, capsulotomy with repair resulted in no anterior capsular defects when compared with capsulectomy. These results may support improved THA stability observed after DAA with capsular repair despite posterior soft tissue releases.

Level of Evidence

Level III, prospective cohort study.

Hospital Adverse Events and Perioperative Outcomes in Bilateral Direct Anterior Approach Total Hip Arthroplasty

11-11-2019 – Jesus M. Villa, Tejbir S. Pannu, Carlos A. Higuera, Juan C. Suarez, Preetesh D. Patel, Wael K. Barsoum

Journal Article

Background

Perioperative hospital adverse events represent a significant outcome that is often overlooked. Even “minor events” such as fever or tachycardia may lead to significant costs due to workup tests, interconsultations, and/or increased length of stay (LOS). The optimal timing of bilateral direct anterior approach total hip arthroplasty (DAA-THA) remains unsettled. Consequently, we wanted to compare hospital LOS, discharge disposition, hospital adverse events (major and minor), and transfusion rates between simultaneous and staged bilateral DAA-THA.

Methods

A retrospective chart review was conducted on a consecutive series of 347 primary bilateral DAA-THAs (204 patients) performed by 2 surgeons in a single institution (2010-2016). The hips finally included were categorized as simultaneous (Sim-n = 61), staged 1 (Stg1-n = 143), or staged 2 (Stg2-n = 143). We also compared simultaneous with staged surgeries performed ≤1 and >1 year apart. Baseline demographics, LOS, discharge disposition, hospital adverse events, and transfusions were assessed.

Results

The simultaneous group had significantly younger patients and a higher proportion of males when compared with the staged groups and showed significant longer LOS 2.61 (Sim) vs 2.06 (Stg1) vs 1.63 (Stg2) days, P < .001, lower proportion of home discharge 77% (Sim) vs 91.6% (Stg1) vs 96.5% (Stg2), P < .001, as well as higher (overall) rate of adverse events 31.1% (Sim) vs 28.7% (Stg1) vs 14.0% (Stg2), P = .003 and transfusions 45.9% (Sim) vs 6.3% (Stg1) vs 7.0% (Stg2), P < .001. However, most transfusions were autologous 37.7% (Sim) vs 3.5% (Stg1) vs 0% (Stg2), P < .001.

Conclusion

Our data show that bilateral DAA-THAs performed in a staged fashion, rather than simultaneously, have a shorter hospital LOS and decreased rates of adverse events and overall transfusions. Notwithstanding, simultaneous surgery should still be considered an option in selected patients.

Level of Evidence

Level III.

Accuracy and Validity of Computer Adaptive Testing for Outcome Assessment in Patients Undergoing Total Hip Arthroplasty

26-11-2019 – Samik Banerjee, Otho Plummer, Joseph A. Abboud, Gregory K. Deirmengian, Eric A. Levicoff, P. Maxwell Courtney

Journal Article

Background

Probability-based computer algorithms that reduce patient burden are currently in high demand. These computer adaptive testing (CAT) methods improve workflow and reduce patient frustration, while achieving high measurement precision. In this study, we evaluated the accuracy and validity of the CAT Hip Disability and Osteoarthritis Outcome Score (HOOS) and the Hip Disability and Osteoarthritis Outcome Score Joint Replacement (HOOS-JR) by comparing them to the full version of these scoring systems in a subset of patients who had undergone total hip arthroplasties.

Methods

A previously developed CAT HOOS and HOOS-JR was applied to 354 and 1547 HOOS and HOOS-JR patient responses, respectively. Mean, standard deviations, Pearson’s correlation coefficients, interclass correlation coefficients, frequency distribution plots, and Bland-Altman plots were used to compare the precision, validity, and accuracy between CAT scores and full-form scores.

Results

By modifying the questions to past responses, the CAT HOOS demonstrated a mean reduction of 30% of questions (28 vs 40 questions). There were no significant differences between the full HOOS and CAT HOOS with respect to pain (P = .73), symptoms (P = .94), quality of life (P = .99), activities of daily living (P = .82), and sports (P = .99). There were strong linear relationships between the CAT versions and the standard questionnaires (r > 0.99). The Bland-Altman plot showed that differences between CAT HOOS and full HOOS were independent of the overall scores.

Conclusion

The CAT HOOS and HOOS-JR have high correlation and require fewer questions to finish compared to the standard full-form questionnaires. This may represent a reliable and practical alternative that may be less burdensome to patients and may help improve compliance for reporting outcome metrics.

Comparison of Posterior Cruciate-Retaining and High-Flexion Cruciate-Retaining Total Knee Arthroplasty Design

05-11-2019 – Won-Gyun Lee, Eun-Kyoo Song, Seung-Won Choi, Quan He Jin, Jong-Keun Seon

Journal Article

Background

High-flexion prostheses have been developed to achieve deep flexion after total knee arthroplasty. The purpose of this study is to compare standard Nex
Gen (CR, cruciate-retaining) and high-flexion Nex
Gen (CR-flex) total knee prostheses in terms of range of motion, clinical and radiologic outcomes, rates of complications, and survivorship in long-term follow-up.

Methods

From January 2000 to December 2008, 423 consecutive knees underwent total knee arthroplasty using standard CR or CR-flex prostheses. Fifty-three patients were lost to follow-up or declined to participate and 54 died, leaving 290 knees. The minimum duration of follow-up was 8 years (mean 10.1 years). Physical examination and knee scoring of patients were assessed preoperatively, at 6 months and 1 year after surgery, and annually thereafter. Supine anteroposterior and lateral radiographs and standing anteroposterior hip-to-ankle radiographs were obtained preoperatively and at each follow-up.

Results

Mean postoperative range of motions in the standard CR group and the CR-flex group were similar, showing no significant difference between the 2 groups (P = .853). At the time of the final follow-up, mean total Hospital for Special Surgery scores were similar between the 2 groups (P = .118). Mean Knee Society pain (P = .325) and function scores (P = .659) were also comparable between the 2 groups. Western Ontario and Mc
Master Universities Osteoarthritis Index score showed no intergroup difference either (P = .586). The mean hip-knee-ankle angle at the final follow-up was approximately the same (P = .940). Mean coronal angles of femoral and tibial component at final follow-up were also similar (P = .211 and P = .764, respectively). The prevalence of the radiolucent line was 0.6% in the standard CR group and 0.9% in the CR-flex group. Estimated survival rate according to Kaplan-Meier survival analysis was 97.2% in the standard CR group and 95.6% in the CR-flex group at mean follow-up of 10.1 years.

Conclusion

This study suggests that excellent clinical and radiographic outcomes could be achieved with both standard and high-flexion CR total knee designs. High-flexion CR prosthesis did not show any advantages over the standard design.

Sagittal Stability and Implant Design Affect Patient Reported Outcomes After Total Knee Arthroplasty

19-11-2019 – Christopher W. Jones, Hans Jacobs, Sarah Shumborski, Simon Talbot, Andrew Redgment, Roger Brighton, William L. Walter

Journal Article

Background

Joint stability is one of the goals of any joint replacement. The contribution of prosthesis design to sagittal stability in total knee arthroplasty (TKA) has emerged as an area of interest. The purpose of this study was to evaluate the sagittal stability of four prosthesis types and determine the effect on patient reported outcome measures (PROMs).

Methods

A matched-cohort cross-sectional study was performed on 60 patients after TKA at 1-year follow-up. Three surgeons performed 10 medially stabilized (MS) TKA and 10 non-MS TKA. Sagittal stability was assessed by a blinded observer using a KT-1000 arthrometer, Lachman’s test, and the anterior drawer test. PROMs (Oxford, Knee Injury and Osteoarthritis Outcome Score, Western Ontario and Mc
Master Universities Osteoarthritis Index, Forgotten joint score) and visual analog scale assessed function and satisfaction.

Results

MS TKA had significantly decreased translation on KT-1000 and improved stability compared with non-MS TKA (P < .05). Increased PROMs were demonstrated in the MS TKA group compared with the non-MS TKA group (P < .05). When divided based on objective stability, regardless of the prosthesis type, patients with a stable knee had superior PROMs (P < .05), particularly in sport-related questions.

Conclusion

The MS TKA had significantly greater sagittal stability, improved PROMs, and satisfaction compared with non-MS TKA. Independent of prosthesis design, patients with greater sagittal stability demonstrated improved PROMs.

Varus-Valgus Constraint in Primary Total Knee Arthroplasty: Axa0Short-Term Solution but Will It Last?

05-11-2019 – Robert J. Avino, Connor A. King, David C. Landy, John M. Martell

Journal Article

Background

Prostheses with varus-valgus constraint (VVC) are increasingly utilized in primary total knee arthroplasty (TKA) to address coronal malalignment and instability though little is known regarding the association between added constraint and aseptic loosening. We sought to systematically review the literature for reports of VVC in primary TKA and meta-analyze clinical results and implant survival.

Methods

PubMed was searched using broad terms to identify articles reporting VVC in primary TKA. Any article reporting clinical or survival outcomes was included. Clinical scores, close to 2 years postoperatively were converted to standardized mean differences, and the latest survival estimates were weighted using the inverse of their variance and meta-analyzed.

Results

Three hundred ninety-two search results were reviewed identifying 30 relevant articles reporting on 3620 knees in total. The estimate for the improvement in clinical scores postoperatively was 3.1 standard deviations (95% confidence interval 2.6-3.6). The estimate for implant revision slowly increased from 1% at 2 years to 2% at 6 years and then began to increase more rapidly beyond this point. The estimated revision rate was 9% by 12 years and 28% by 20 years. This revision rate estimate was stable with and without the inclusion of outlying studies.

Conclusion

VVC in primary TKA is associated with significant clinical improvement without significant risk of early failure. Meta-regression estimates raise concerns for significant revision risk with extended follow-up, especially beyond 5 years. In the absence of new data, VVC should continue to be used cautiously in the primary TKA.

Comparison of Gap Balancing vs Measured Resection Technique in Patients Undergoing Simultaneous Bilateral Total Knee Arthroplasty: One Technique per Knee

05-11-2019 – Sachin R. Tapasvi, Anshu Shekhar, Shantanu S. Patil, Matthew V. Dipane, Madhav Chowdhry, Edward J. McPherson

Journal Article

Background

Total knee arthroplasty requires careful surgical technique to attain the goal of a well-aligned and symmetrically balanced knee. Soft tissue balance and correct femoral component rotation are paramount in achieving these goals. The two competing techniques to select femoral component rotation and soft tissue balance are the gap balance technique and the measured resection technique.

Methods

We performed a randomized, prospective study to compare the two techniques in patients undergoing simultaneous bilateral total knee arthroplasty, whereby one technique was performed in each knee. Fifty (50) subjects were enrolled into the study. The inclusion criteria were osteoarthritic varus knee deformities with similar deformities in both knees. Subjects were followed up for a minimum of two years.

Results

The knees balanced via the gap balance technique had significantly more posterior medial bone removed from the femur than those knees balanced via the measured resection technique (P < .001). Knees in the gap balance group tended to require more medial knee releases in extension and tended to have smaller sized femoral components as a result of cutting more bone from the femur in flexion. The modular tibial polyethylene bearing tended to be thicker in the gap balance group. Despite these differences, average knee flexion and functional revised Oxford Knee Scores at 2-year follow-up were not statistically different.

Conclusion

At 2-year follow-up, there were no differences between the function and scores using the two techniques. Long-term follow-up will be necessary to evaluate any differences in long-term durability.

Intraoperative Practice Variability in Total Knee Arthroplasty

25-11-2019 – Liam C. Bosch, Samuel B. Beger, Stephen T. Duncan, Stefano M.P. Rossi, Peter K. Sculco, C. Lowry Barnes, Derek F. Amanatullah

Journal Article

Background

Considerable practice variability exists among orthopedic surgeons performing total knee arthroplasty (TKA). The purpose of this study is to understand what TKA surgical and perioperative techniques are standard among high-volume academic knee arthroplasty surgeons.

Methods

A written survey with 59 questions regarding management preferences in TKA was distributed by the 2018 John N. Insall Traveling Fellows to all arthroplasty-trained attending physicians at 13 medical centers, with 45 responses recorded.

Results

Surveyed surgeons performed unicompartmental knee arthroplasty (88%) and bilateral TKA (87%). Most surveyed surgeons rarely or never performed outpatient primary TKA (71%). Conventional alignment guides and cemented implants were used by 80% of respondents. Most surgeons used posterior-stabilized implants (67%), followed by cruciate-retaining (20%), ultracongruent (20%), and medial congruent or medial pivot designs (17.8%). Surveyed surgeons frequently or always resurfaced the patella (73%), used a tourniquet for the entire case (73%), and used tranexamic acid for all TKAs (91%). The most common locations for intra-articular anesthetic injection were the arthrotomy (91%), the periosteum (84%), and the medial posterior capsule (82%). Saline (62%) and dilute iodine (47%) were the most common irrigation fluids. The arthrotomy was most commonly closed with running barbed suture (60%) followed by interrupted vicryl (40%). Skin closure was predominantly with running monocryl (60%) followed by staples (29%). Anticoagulation for TKA was primarily aspirin 81 mg BID (60%).

Conclusion

There was considerable variability among surgeons polled although a strong preference for more conventional and less developmental techniques prevailed.

The Association Between Anxiety, Depression, and Locus of Control With Patient Outcomes Following Total Knee Arthroplasty

12-11-2019 – Joshua Xu, Joshua Twiggs, David Parker, Jonathan Negus

Journal Article

Background

We aimed to determine how preoperative anxiety, depression, and locus of control (Lo
C) might predict patient outcomes following total knee arthroplasty (TKA).

Methods

Patients undergoing TKA were prospectively recruited over an 18-month period. The Western Ontario and Mc
Master Universities Osteoarthritis Index (WOMAC) was used to assess TKA outcomes. The Short Form-12, Hospital Anxiety and Depression Score, and Lo
C surveys were completed by the patients to assess their psychosocial state. These scores were collected preoperatively and at 6 weeks, 18 weeks, and 1 year postoperation.

Results

The final cohort consisted of 136 patients. Greater preoperative depression (P = .004) and anxiety (P = .001) scores were correlated with worse total WOMAC score at 6 weeks and 18 weeks postoperatively, respectively. A poorer preoperative Short Form-12 mental score was also correlated with a worse total WOMAC score at 6 weeks postoperatively (P = .007). Greater tendency toward an internal Lo
C preoperatively was correlated with better WOMAC pain (P < .001) and function (P = .003) scores at 18 weeks postoperatively. However, there was no correlation between preoperative external Lo
C and postoperative WOMAC score. There was also no correlation between any of the preoperative psychosocial measures and WOMAC score at 1 year postoperatively.

Conclusion

We identified a group of patients whose psychosocial markers predicted them to have worse outcomes in the short to medium term even though they normalized to satisfactory outcomes at 1 year postoperatively. Identifying this group could allow for targeted intervention with an adjustment of expectations and thus more effective recovery.

Improvements in Objectively Measured Activity Behaviors Do Not Correlate With Improvements in Patient-Reported Outcome Measures Following Total Knee Arthroplasty

15-11-2019 – Emmanuel Frimpong, Dick R. van der Jagt, Lipalo Mokete, Jurek Pietrzak, Yusuf S. Kaoje, Anne Smith, Joanne A. McVeigh, Rebecca M. Meiring

Journal Article

Background

Activity monitors have added a new dimension to our ability to objectively measure physical activity in patients undergoing total knee arthroplasty (TKA). The aim of the study is to assess whether changes in the time spent sitting, standing, and stepping were associated with changes in patient-reported outcome measures (PROMs) before and after TKA.

Methods

Valid activ
PAL data (>3 days) and PROMs were obtained from 49 men and women (mean SD age, 62.8 8.6 years; body mass index, 33.8 7.1 kg/m2) who underwent primary TKA, before and at 6 weeks or 6 months after surgery. Patient-reported symptoms of pain, stiffness, and knee function were obtained using the Knee injury and Osteoarthritis Outcome Score and Oxford Knee Score questionnaires.

Results

Mean (SD) Knee injury and Osteoarthritis Outcome Score (80.1 16.3 to 41.6 6.5, P < .001) and Oxford Knee Score (12.0 9.8 to 17.7 22.8, P < .001) scores improved 6 months after TKA. Walking time (mean 95% confidence interval; min/d) increased from before (79 67-91) to 6 months after TKA (101 88-114, P = .006). Standing time (318 276-360 to 321 291-352, P = .782) and sitting time (545 491-599 to 509.0 459.7-558.3, P = .285) did not change from before to 6 months after TKA. Participants took more steps (2559 2128-2991 to 3515 2983-4048 steps/day, P = .001) and accumulated more steps (31 30-34 to 34 33-35 steps/min, P < .001) after TKA compared to before. There were no associations between changes in activity behaviors and changes in PROMs (P > .05).

Conclusion

Despite improvements in self-reported knee pain and functional ability, these changes do not correlate with improvements in objectively measured light-intensity and sedentary activity behaviors.

Does Activity-Based Rehabilitation With Goal Attainment Scaling Increase Physical Activity Among Younger Knee Arthroplasty Patients? Results From the Randomized Controlled ACTION Trial

20-11-2019 – Alexander Hoorntje, Suzanne Witjes, P. Paul F.M. Kuijer, Johannes B.J. Bussmann, Herwin L.D. Horemans, Gino M.M.J. Kerkhoffs, Rutger C.I. van Geenen, Koen L.M. Koenraadt

Journal Article

Background

Especially in younger knee osteoarthritis patients, the ability to perform physical activity (PA) after knee arthroplasty (KA) is of paramount importance, given many patients’ wish to return to work and perform demanding leisure time activities. Goal Attainment Scaling (GAS) rehabilitation after KA may improve PA because it uses individualized activity goals. Therefore, our aim was to objectively quantify PA changes after KA and to compare GAS-based rehabilitation to standard rehabilitation.

Methods

Data were obtained from the randomized controlled ACTION trial, which compares standard rehabilitation with GAS-based rehabilitation after total and unicompartmental KA in patients <65 years of age. At 2 time points, preoperatively and 6 months postoperatively, 120 KA patients wore a validated 3-dimensional accelerometer for 1 consecutive week. Data were classified as sedentary (lying, sitting), standing, and active (walking, cycling, running). Repeated measures analysis of variance was used to compare PA changes over time.

Results

Complete data were obtained for 97 patients (58% female), with a mean age of 58 years (±4.8). For the total group, we observed a significant increase in PA of 9 minutes (±37) per day (P = .01) and significant decrease in sedentary time of 20 minutes (±79) per day (P = .02). There was no difference in standing time (P = .11). There was no difference between the control group and the intervention group regarding changes in PA, nor between the total KA group and the unicompartmental KA group.

Conclusion

We found a small but significant increase in overall PA after KA, but no difference between GAS-based rehabilitation and standard rehabilitation. Likely, enhanced multidisciplinary perioperative strategies are needed to further improve PA after KA.

The Uptake of New Knee Replacement Implants in the UK: Analysis of the National Joint Registry for England and Wales

08-12-2019 – Chris M. Penfold, Ashley W. Blom, J. Mark Wilkinson, Andrew Judge, Michael R. Whitehouse

Journal Article

Background

Knee replacement (KR) surgery is one of the most common elective procedures in the UK. A large number of different KR implant brands are in use in the UK, which may contribute to variation in uptake and patient outcomes.

Methods

A cohort of 722,178 primary KRs performed for osteoarthritis (with or without other indications) by 2675 consultant surgeons between 2008 and 2017 in England and Wales from the National Joint Registry was examined. We described the uptake of new (first use >2008) KR implant brands, and variation in uptake by consultant surgeons (primary objectives). We explored consultant-level/patient-level factors associated with use/receipt of new implant brands with multilevel logistic regression models (secondary objectives).

Results

Sixty-five new KR implant brands were used in 22,134 KRs (3.1%) by 759 consultants (28.4%) between 2008 and 2017. Consultants used a median of 1 new brand (interquartile range = 1-2, max = 8) in 4.1% (interquartile range = 1.1%-12.3%) of their KRs. Younger patients (<55 vs 55-80, odds ratio OR = 1.63, 95% confidence interval CI = 1.54-1.72) and women (OR = 1.17, 95% CI = 1.13-1.22) had higher odds of receiving a new rather than established brand. Consultants who used more different implant brands had higher odds of using new brands (OR/additional implant/year = 2.57, 95% CI = 2.37-2.79).

Conclusion

A large number of new KR implant brands have been introduced in the National Joint Registry since 2008. A quarter of consultants have tried a new implant brand but have used them in only a small proportion of primary KRs in this period. Younger, healthier patients are more likely to receive new implant brands, and they are more likely to be used by surgeons who use many different implant brands.

Development of Preoperative Prediction Models for Pain and Functional Outcome After Total Knee Arthroplasty Using The Dutch Arthroplasty Register Data

13-11-2019 – Jaap J. Tolk, J. (Erwin) H. Waarsing, Rob P.A. Janssen, Liza N. van Steenbergen, Sita M.A. Bierma-Zeinstra, Max Reijman

Journal Article

Background

One of the main determinants of treatment satisfaction after total knee arthroplasty (TKA) is the fulfillment of preoperative expectations. For optimal expectation management, it is useful to accurately predict the treatment result. Multiple patient factors registered in the Dutch Arthroplasty Register (LROI) can potentially be utilized to estimate the most likely treatment result. The aim of the present study is to create and validate models that predict residual symptoms for patients undergoing primary TKA for knee osteoarthritis.

Methods

Data were extracted from the LROI of all TKA patients who had preoperative and postoperative patient-reported outcome measures registered. Multivariable logistic regression analyses were performed to construct predictive algorithms for satisfaction, treatment success, and residual symptoms concerning pain at rest and during activity, sit-to-stand movement, stair negotiation, walking, performance of activities of daily living, kneeling, and squatting. We assessed predictive performance by examining measures of calibration and discrimination.

Results

Data of 7071 patients could be included for data analysis. Residual complaints on kneeling (female 72%/male 59%) and squatting (female 71%/male 56%) were reported most frequently, and least residual complaints were scored for walking (female 16%/male 12%) and pain at rest (female 18%/male 14%). The predictive algorithms were presented as clinical calculators that present the probability of residual symptoms for an individual patient. The models for residual symptoms concerning sit-to-stand movement, stair negotiation, walking, activities of daily living, and treatment success showed acceptable discriminative values (area under the curve 0.68-0.74). The algorithms for residual complaints regarding kneeling, squatting, pain, and satisfaction showed less favorable results (area under the curve 0.58-0.64). The calibration curves showed adequate calibration for most of the models.

Conclusion

A considerable proportion of patients have residual complaints after TKA. The present study showed that demographic and patient-reported outcome measure data collected in the LROI can be used to predict the probability of residual symptoms after TKA. The models developed in the present study predict the chance of residual symptoms for an individual patient on 10 specific items concerning treatment success, functional outcome, and pain relief. This prediction can be useful for individualized expectation management in patients planned for TKA.

Rehabilitation After Total Knee Arthroplasty: Do Racial Disparities Exist?

06-12-2019 – Alyson M. Cavanaugh, Mitchell J. Rauh, Caroline A. Thompson, John E. Alcaraz, Chloe E. Bird, Todd P. Gilmer, Andrea Z. LaCroix

Journal Article

Background

Racial disparities in functional outcomes after total knee arthroplasty (TKA) exist. Whether differences in rehabilitation utilization contribute to these disparities remains to be investigated.

Methods

Among 8349 women enrolled in the prospective Womens Health Initiative cohort who underwent primary TKA between 2006 and 2013, rehabilitation utilization was determined through linked Medicare claims data. Postacute discharge destination (home, skilled nursing facility, and inpatient rehabilitation facility), facility length of stay, and number of home health physical therapy (HHPT) and outpatient physical therapy (OPPT) sessions were compared between racial groups.

Results

Non-Hispanic black women had worse physical function (median score, 65 vs 70) and higher likelihood of disability (13.2% vs 6.9%) than non-Hispanic white women before surgery. After TKA, black women were more likely to be discharged postacutely to an institutional facility (64.3% vs 54.5%) than white women, were more likely to receive HHPT services (52.6% vs 47.8%), and received more HHPT and OPPT sessions. After stratification by postacute discharge setting, the likelihood of receipt of HHPT or OPPT services was similar between racial groups. No significant difference in receipt of HHPT or OPPT services was found after use of propensity score weighting to balance health and medical characteristics indicating severity of need for physical therapy services.

Conclusion

Rehabilitation utilization was generally comparable between black and white women who received TKA when accounting for need. There was no evidence of underutilization of post-TKA rehabilitation services, and thus disparities in post-TKA functional outcomes do not appear to be a result of inequitable receipt of rehabilitation care.

The Effect of Bone Quality on Tibial Component Migration in Medial Cemented Unicompartmental Knee Arthroplasty. Axa0Prospective Cohort Study Using Dual X-Ray Absorptiometry andxa0Radiostereometric Analysis

17-11-2019 – Daan Koppens, Søren Rytter, Jesper Dalsgaard, Ole G. Sørensen, Torben B. Hansen, Maiken Stilling

Journal Article

Background

Periprosthetic bone mineral density (BMD) may influence implant fixation and subsequent loosening. Unicompartmental knee arthroplasty (UKA) restores normal knee kinematics and load distribution to the surrounding bone. We studied the influence of systemic and periprosthetic BMD of the proximal tibia on migration of the tibial component of cemented medial UKA.

Methods

The cohort was dichotomized into a normal BMD group (T-score ≥ −1; n = 37) and a low BMD group (T-score < −1; n = 28) according to World Health Organization criteria. BMD of the proximal tibia and migration of the tibial component were measured with dual X-ray absorptiometry scans and stereoradiographs with 2-year follow-up.

Results

Patients with normal systemic BMD had an 11% to15% higher BMD in all regions of interest (ROIs) compared to patients with low systemic BMD throughout follow-up. Over time, a decrease in periprosthetic BMD in ROI 1-3 was seen for both groups. The operated knees and contralateral knees showed a similar reduction in BMD in all ROIs between preoperative and 24 months.

Between 12 and 24 months, the normal BMD group migrated (maximal total point motion) 0.03 mm (95% confidence interval, −0.01, 0.08) and the low BMD group migrated 0.02 mm (95% confidence interval, −0.03, 0.07). Migration over time was not influenced by change in periprosthetic BMD.

Conclusion

Migration of cemented medial tibial UKA was low until 24 months and was neither affected by preoperative systemic BMD nor affected by postoperative change in periprosthetic BMD. This suggests good long-term fixation despite an index difference in proximal tibial BMD.

The Effect of Dexamethasone on Postoperative Blood Glucose in Patients With Type 2 Diabetes Mellitus Undergoing Total Joint Arthroplasty

26-11-2019 – Dexter C. Allen, Nicole A. Jedrzynski, James D. Michelson, Michael Blankstein, Nathaniel J. Nelms

Journal Article

Background

Perioperative glucocorticoids are routinely administered to patients undergoing total joint arthroplasty (TJA) to decrease postoperative pain and nausea. However, there is concern regarding the effects of glucocorticoids on perioperative glucose control in diabetes. The goal of this study is to determine if administration of preoperative dexamethasone to diabetic patients is significantly associated with hyperglycemia and increased insulin requirements in the immediate postoperative period after TJA and to identify risk factors for postoperative hyperglycemia immediately after TJA.

Methods

A retrospective review of type 2 diabetic patients undergoing TJA from 2010 to 2015 (n = 285) was undertaken to evaluate the effect of dexamethasone on postoperative glucose control. Preoperative baseline characteristics were compared between patients who did and did not receive 8 mg of intravenous dexamethasone preoperatively. Postoperative glucose and insulin requirements were evaluated with respect to dexamethasone dosing. Statistical analysis was performed using logistic regression models.

Results

Dexamethasone administration did not correlate with the maximum postoperative blood glucose (P = .78). There was a significantly higher initial postoperative blood glucose after intravenous dexamethasone administration (P < .01). Dexamethasone administration was associated with increased aspart insulin requirements on postoperative day 0 (P = .04). However, preoperative hemoglobin A1c was most strongly associated with postoperative glucose control.

Conclusion

Preoperative dexamethasone administration to diabetic patients was associated with an initial increase in blood glucose and increased insulin requirement on postoperative day 0. Yet the observed effect on glucose control in diabetic patients may not outweigh the known clinical benefits of perioperative glucocorticoids.

Nuisance Symptoms in Total Joint Arthroplasty: Prevalence and Impact on Patient Satisfaction

19-11-2019 – Thomas J. Wood, Danielle T. Petruccelli, Daniel M. Tushinski, Mitchell J. Winemaker, Justin de Beer

Journal Article

Background

While hip and knee total joint arthroplasty (TJA) patients experience marked improvement in pain relief and function, many patients experience nuisance symptoms, which may cause discomfort and dissatisfaction.

Methods

A prospective survey study to determine type and prevalence of hip/knee TJA nuisance symptoms and impact on patient satisfaction at 1 year postoperative was conducted. The survey determined occurrence of common nuisance symptoms (eg, localized pain, swelling, instability, stiffness) and impact on overall satisfaction rated on a 10-point visual analog scale (VAS). Survey responses were analyzed using descriptive statistics.

Results

The sample comprised 545 TJA patients who completed the survey: 335 knees (61%) and 210 hips (39%). Among knees, the most commonly reported nuisance symptoms and associated impact on satisfaction included difficulty kneeling (78.2%; VAS, 4.3; SD, 3.3), limited ability to run/jump (71.6%; VAS, 3.3; SD, 3.3), and numbness around incision (46.3%; VAS, 3.8; SD, 3.3). Overall, 94% of knee patients experienced at least 1 nuisance symptom at 1 year, reporting mean satisfaction of 9/10 (SD, 1.7). Among hips, the most commonly reported nuisance symptoms and associated impact on satisfaction were limited ability to run/jump (68.6%; VAS, 3.4; SD, 3.4), thigh muscle pain (44.8%; VAS, 3; SD, 2.7), and limp when walking (37.6%; VAS, 4.1; SD, 3.2). Overall, 88% of hip patients experienced at least 1 self-reported nuisance symptom at 1 year, reporting mean satisfaction of 8.9/10 (SD, 1.7).

Conclusion

Nuisance symptoms after hip/knee TJA are very common. Despite the high prevalence, impact on overall satisfaction is minimal and patient satisfaction remains high. Careful preoperative counseling regarding prevalence is prudent and will help establish realistic expectations following TJA.

Femoral Head and Neck Fenestration Through a Direct Anterior Approach Combined With Compacted Autograft for the Treatment of Early Stage Nontraumatic Osteonecrosis of the Femoral Head: Axa0Retrospective Study

26-11-2019 – Qiuru Wang, Donghai Li, Zhouyuan Yang, Pengde Kang

Journal Article

Background

This study aimed to evaluate the effect of femoral head and neck fenestration combined with compacted autograft (light bulb procedure) through a direct anterior approach for early stage nontraumatic osteonecrosis of the femoral head.

Methods

We conducted a retrospective cohort study investigating 66 hips undergoing the light bulb procedure through the direct anterior approach (light bulb group) and 59 hips undergoing traditional core decompression (control group). Visual analog scale pain scores and range of hip motion were evaluated before discharge to assess the quality of functional recovery. Follow-up was conducted at 6 weeks, 3 months, 6 months, and annually after surgery until 4 years. The clinical effectiveness was evaluated by Harris hip score and the University of California Los Angeles activity-level score. Patients were followed up with postoperative X-ray and computed tomography. Survival was compared between the 2 groups by radiographic progression and receiving total hip arthroplasty.

Results

There was no significant difference in quality of functional recovery between the 2 groups. There were no significant differences in clinical outcomes within 1 year after surgery. Patients in the light bulb group had significantly better Harris hip scores and University of California Los Angeles activity-level scores from 2 years after surgery to the end of follow-up. During the 4-year follow-up, significantly fewer patients in light bulb group had radiographic progression (22.7% vs 44.1%) or received total hip arthroplasty (15.2% vs 30.5%).

Conclusions

The light bulb procedure through a direct anterior approach offers significantly better results for the treatment of early stage nontraumatic osteonecrosis of the femoral head compared with traditional core decompression.

Analysis of Readability, Quality, and Content of Online Information Available for “Stem Cell” Injections for Knee Osteoarthritis

05-11-2019 – Mitchell K. Ng, Michael A. Mont, Nicolas S. Piuzzi

Journal Article

Background

An increasing number of patients use the Internet to obtain health information, although online information is unregulated and highly variable. We aimed to assess the readability, quality, and content of online information available for “stem cell” injections for knee osteoarthritis.

Methods

A cross-sectional analysis was performed on March 2019, inputting the search term “stem cells osteoarthritis” into the 3 most popular global search engines: Google, Bing, and Yahoo. The first 50 search results of each engine were evaluated/categorized. Readability was assessed using Flesch-Kincaid Ease/Grade Level. Quality/content was assessed through DISCERN score and a stem cell content score created for this study.

Results

Eighty-two websites were analyzed (18 academic websites, 21 commercial, 13 government/non-profit, 30 physician). Among all websites, mean Flesch-Kincaid readability was 35.9 with a grade level of 13.6. The average DISCERN score was 49.5/80 with statistically significant differences between academic vs physician websites (64.6 vs 38.1, P < .001), and commercial vs physician websites (52.3 vs 38.1, P = .001). Mean stem cell content score was 6.5/19 with a statistically significant difference between academic vs physician websites (8.5 vs 5.1, P = .007).

Conclusion

Readability of online materials available for patients regarding “stem cell” treatment for knee osteoarthritis is significantly higher than the grade 6-8 recommended by the National Institutes of Health. The quality and content of websites is highly variable, with physician websites scoring especially low. Improving quality and readability of online materials that discuss risks/benefits of stem cell injections may potentially enhance the physician-patient therapeutic alliance and indirectly lead to better patient outcomes.

New Implant Introduction in Total Hip Arthroplasty Using Radiostereometric Analysis: A Cautionary Note

05-11-2019 – Abigail R. Frazer, Michael Tanzer

Journal Article

Background

It has been proposed that the introduction of new hip implant technology in orthopedic surgery be conducted in a more controlled manner in order to properly ensure patient safety and the likelihood of favorable outcomes. This stepwise introduction would first require a prospective randomized study in a small cohort of patients, using radiostereometric analysis (RSA). The aim of this study is to determine if the recent literature supports the use of RSA as an early screening tool to accurately predict the long-term outcomes of cementless femoral stems.

Methods

A review of the recent published literature identified 11 studies that used RSA to predict the long-term stability of a cementless femoral component. These RSA predictive data were compared to the 10-year revision rate reported in the Australian Registry or in the published literature to determine its reliability.

Results

RSA data did not universally predict long-term stem fixation. In 2 of the 11 cases (18%), the RSA study incorrectly predicted the ability of the cementless stem to reliably osseointegrate. Of the 9 stems considered stable in the RSA studies, the 10 year registry and literature data confirmed that 6 implants had a low revision rate and were well performing. One stem has not performed well clinically and has been listed as having a higher than anticipated rate of revision in the registry. Two stems do not have sufficient follow-up. Of the 2 stems RSA predicted to do poorly, 1 is well performing at 10 years, and 1 has a high revision rate at 8 years.

Conclusion

In the stepwise introduction of new hip implants, RSA should be best considered as an adjunct tool in deciding whether or not an implant should be evaluated in a larger multicenter clinical studies, rather than the sole criterion.

Outcomes of Same-Day Discharge After Total Hip Arthroplasty in the Medicare Population

02-11-2019 – Oren I. Feder, Katherine Lygrisse, Lorraine H. Hutzler, Ran Schwarzkopf, Joseph Bosco, Roy I. Davidovitch

Journal Article

Background

There is an increasing utilization of same-day discharge total hip arthroplasty (SDD THA). As the Center for Medicare and Medicaid Services considers removing THA from the inpatient-only list, there is likely to be a significant increase in the number of Medicare patients undergoing SDD THA. Thus, there is a need to report on outcomes of SDD THA in this population.

Methods

A retrospective review was performed on 850 consecutive SDD THA patients including 161 Medicare patients. We compared failure to launch, complication, emergency department visit, and 90-day readmission rates between the Medicare and non-Medicare cohorts.

Results

The Medicare group was older and had less variability in their admission diagnosis. There was no significant difference in failure to launch, complication, emergency department visit, or 90-day readmission rates between Medicare and non-Medicare groups.

Conclusion

The benefits of SDD THA can be safely extended to the carefully indicated and motivated Medicare patient.

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

Enhanced Selection of Candidates for Same-Day and Outpatient Total Knee Arthroplasty

07-11-2019 – Meredith G. Moore, David P. Brigati, Tom J. Crijns, Thomas R. Vetter, William R. Schultz, Kevin J. Bozic

Journal Article

Background

Medicare removed total knee arthroplasty (TKA) from its inpatient-only list and private insurers created ambulatory surgical codes; these changes bring about logistical challenges for TKA episode planning. We identified preoperatively determined factors associated with hospital length of stay for (1) same-day discharge (SDD) and (2) inpatient TKA defined by Medicare’s 2-midnight rule benchmark.

Methods

We retrospectively reviewed 325 consecutive unilateral primary TKAs performed on patients completing the Perioperative Surgical Home preoperative optimization pathway within a single hospital system. Stepwise logistic regression modeling was performed to identify preoperatively determined factors associated with (1) SDD and (2) inpatient TKA. We compared these models’ ability to discern the length of stay category to the Risk Assessment and Prediction Tool (RAPT) score alone.

Results

The cohort included 32 (10%) SDD, 189 (58%) next-day discharges, and 104 (32%) inpatients. Lower body mass index (BMI; odds ratio OR, 0.92; 95% CI, 0.85-0.1.0; P = .04) and fewer self-reported allergies (OR, 0.66; 95% CI, 0.46-0.95; P = .03) were associated with SDD. The SDD model outperformed the RAPT alone (C-statistic, 0.73 vs 0.52; P < .01). Older age (OR, 0.96; P = .04), higher BMI (OR, 0.93; P 0.01), lower RAPT score (OR, 1.2; P = .04), and later surgery start time (OR, 0.80; P < .01) were associated with inpatient discharge. The inpatient model outperformed the RAPT alone (C-statistic, 0.74 vs 0.62; P < .01).

Conclusion

We identified preoperatively determined factors associated with (1) SDD as BMI and allergies and (2) inpatient TKA as age, BMI, RAPT score, and surgery start time. Hospitals, providers, patients, families, and payers can use this information for TKA episode planning.

What Factors Influence Operative Time in Total Knee Arthroplasty? A 10-Year Analysis in a National Sample

27-11-2019 – Alexander J. Acuña, Linsen T. Samuel, Jaret M. Karnuta, Assem A. Sultan, Andrew M. Swiergosz, Atul F. Kamath

Journal Article

Background

Changes in reimbursement in total knee arthroplasty (TKA) by Centers for Medicare and Medicaid Services (CMS) have been tied to a perceived decrease in the total surgical time required to perform these operations. However, little information is available to CMS about recorded surgical times for TKA across the United States and the variables that drive these values. Therefore, the purpose of our study, is to evaluate (1) changes in operative time over time and (2) factors associated with variations in operative time.

Methods

The National Surgical Quality Improvement Program database was queried to identify all primary TKAs conducted between January 1, 2008, and December 31, 2017. All TKAs conducted within our study period that had operative time data available were included. Multivariable linear models were created to assess factors that influence operative time over the study period.

Results

Our final analysis included 140,890 TKAs. The mean operative time across the study period was found to be 92.60 minutes. Examining quarterly values, operative time stayed within 5 minutes of this mean (range, 89.80-97.51 minutes). Age, sex, functional status, anesthesia type, body mass index, operative year, transfusion requirements, and preoperative laboratory findings significantly influenced operative time (P < .05 for all).

Conclusion

Our analysis indicates that while there are numerous factors that influence procedure duration, operative times have remained stable. This information should be heavily considered in regard to physician reimbursement, because providers are maintaining operative times and work effort while mitigating factors that influence outcomes in the perioperative period.

Effect of Posthospital Syndrome on Discharge Disposition and Healthcare Utilization After Primary Total Joint Arthroplasty

19-11-2019 – Shepard P. Johnson, Peter R. Swiatek, Kevin C. Chung

Journal Article

Background

The aim of this study is to evaluate the impact of posthospital syndrome (PHS), a physiologically deconditioned state experienced by patients after hospitalizations, on postoperative healthcare utilization and discharge disposition following total hip (THA) and knee (TKA) arthroplasty.

Methods

Insurance claims from the Truven Market
Scan Databases were used to perform this cross-sectional study of patients who underwent unilateral, primary THA or TKA between January 2010 and December 2016. PHS, defined as a hospitalization within 90 days before surgery, and non-PHS cohorts were compared. Multivariable logistic regression analyses were used to identify risk of postoperative discharge to an extended care facility (ECF), hospital readmissions, and emergency department visits within 90 days.

Results

This study included 115,465 THA and 190,398 TKA patients who underwent elective surgery for osteoarthritis. PHS was identified in 1.9% and 1.6% of cohorts, respectively, and was more common in patients with higher comorbidities. The PHS cohort had higher crude rates of discharge to ECF (THA 38.8% and TKA 33.8%) and readmissions (21.8% and 18%). Adjusted odds ratios showed that PHS increased risk of disposition to ECF (THA 1.9 and TKA 1.4), readmission (2.8 and 2.0), and emergency department encounters (1.6 and 1.4). Among PHS patients, acute hospitalizations within 30 days of surgery and those lasting greater than 5 days had the highest risk of postoperative healthcare utilization.

Conclusion

In this study of commercially insured patients, those with an acute hospitalization within 90 days before elective total joint arthroplasty were nearly twice as likely to be discharged to an ECF and twice as likely to be readmitted in the global postoperative period.

Surgeon Reimbursement Unchanged as Hospital Charges and Reimbursements Increase for Total Joint Arthroplasty

05-11-2019 – Nicole Durig Quinlan, Dennis Q. Chen, James A. Browne, Brian C. Werner

Journal Article

Background

Despite increasing demands on physicians and hospitals to increase value and reduce unnecessary costs, reimbursement for healthcare services has been under downward pressure for several years. This study aimed to analyze the trend in hospital charges and payments relative to corresponding surgeon charges and payments in a Medicare population for total hip (THA) and knee arthroplasty (TKA).

Methods

The 5% Medicare sample database was used to capture hospital and surgeon charges and payments related to 56,228 patients who underwent primary THA and 117,698 patients who underwent primary TKA between 2005 and 2014. Two values were calculated: (1) the charge multiplier (CM), the ratio of hospital to surgeon charges and (2) the payment multiplier (PM), the ratio of hospital to surgeon payments. Year-to-year variation and regional trends in patient demographics, Charlson Comorbidity Index, length of stay (LOS), CM, and PM were evaluated.

Results

Hospital charges were significantly higher than surgeon charges and increased substantially for both THA (CM increased from 8.7 to 11.5, P < .0001) and TKA (CM increased from 7.9 to 11.4, P < .0001). PM followed a similar trend, increasing for both THA and TKA (P < .0001). LOS decreased significantly for both THA and TKA (P < .0001), while Charlson Comorbidity Index remained stable. Both CM (r2 = 0.84 THA, 0.90 TKA) and PM (r2 = 0.75 THA, 0.84 TKA) were strongly negatively associated with LOS.

Conclusion

Hospital charges and payments relative to surgeon charges and payments have increased substantially for THA and TKA despite stable patient complexity and decreasing LOS.

Streamlining Hospital Treatment of Prosthetic Joint Infection

13-02-2020 – Kevin M. Goodson, James R. Kee, Paul K. Edwards, Amanda J. Novack, Jeffrey B. Stambough, Eric R. Siegel, C. Lowry Barnes, Simon C. Mears

Journal Article

Background

Prosthetic joint infection (PJI) is associated with significant morbidity, mortality, and costs. We developed a fast-track PJI care system using an infectious disease physician to work directly with the TJA service and coordinate in the treatment of PJI patients. We hypothesized that streamlined care of patients with hip and knee PJI decreases the length of the acute hospital stay without increasing the risk of complication or incorrect antibiotic selection.

Methods

A single-center retrospective chart review was performed for all patients treated operatively for PJI. A cohort of 78 fast-track patients was compared to 68 control patients treated before the implementation of the program. Hospital length of stay (LOS) and cases of antibiotic mismatch were primary outcomes. Secondary outcomes, including 90-day readmissions, reoperations, mortality, rate of reimplantation, and 12-month reimplant survival, were compared. Cox regressions were analyzed to assess the effects on LOS of patient demographics and the type of surgery performed.

Results

Average hospital LOS from infection surgery to discharge was significantly lower in the fast-track cohort (3.8 vs 5.7 days; P = .012). There were no episodes of antibiotic mismatch in the fast-track group vs 1 recorded episode in the control group. No significant differences were noted comparing 90-day complications, reimplantation rate, or 12-month reimplant survival rates.

Conclusion

Through the utilization of an orthopedic-specific infectious disease physician, a fast-track PJI protocol can significantly shorten hospital LOS while remaining safe. Streamlining care pathways may help decrease the overall healthcare costs associated with treating PJI.

Two-Stage Treatment for Total Knee Arthroplasty Infection Utilizing an Articulating Prefabricated Antibiotic Spacer

13-02-2020 – Lucian C. Warth, Christopher J. Hadley, Eric L. Grossman

Journal Article

Periprosthetic joint infection represents a serious complication following total knee arthroplasty. In the setting of chronic or age-indeterminate total knee arthroplasty infection, a 2-staged approach has been traditionally the preferred method of treatment over single-stage debridement and reimplantation debridement or debridement, antibiotics and implant retention. Two-stage is the preferred treatment method in North America and has demonstrated better overall success than the single stage techniques. Additionally, the 2-stage method is the preferred treatment for difficult to treat pathogens as well as in patients who have already undergone a previous revision procedure. An articulating prefabricated antibiotic spacer has entered the armamentarium of 2-stage revision knee surgery, and has demonstrated comparable results to custom and static spacers in terms of the primary goal of infection control. Importantly, the potential for enhanced mobility and function hold promise by safely providing a more “livable” knee during the convalescent period prior to definitive reimplantation.

Comparison of Traditional Molded, First-Generation Premolded, and Second-Generation Premolded Antibiotic-Loaded Polymethylmethacrylate Articulating Spacers for Treatment of Chronic Prosthetic Joint Infection of the Knee

13-02-2020 – David K. DeBoer

Journal Article

Background

The purpose of this study was to compare patients who had chronic prosthetic joint infection treated using three methods of articulating polymethylmethacrylate spacers in two-stage reimplantation.

Methods

We identified 77 patients who had chronic prosthetic joint infection with a minimum of one-year follow-up. Reinfection rates were determined using modified International Consensus group criteria.

Results

The overall reinfection rate was 18% (14 of 77 patients). Despite a higher medical comorbidity in the second-generation spacer cohort, there were no statistical differences in reinfection rates between articulating spacer types.

Conclusion

This study suggests that there were no differences in efficacy between the traditional molded, first-generation premolded, and second-generation premolded articulating spacers, but more studies with high level of evidence are needed.

Do Antibiotic-Impregnated Intramedullary Dowels Assist in Eradicating Infection in Total Knee Arthroplasty?

13-02-2020 – Michael M. Kheir, R. Michael Meneghini

Journal Article

Antibiotic-impregnated intramedullary dowels historically have been advocated and are frequently used to facilitate periprosthetic knee infection eradication. They are used for focused delivery of antibiotics into the femoral and tibial intramedullary canals during 2-stage resection utilizing an antibiotic cement spacer. However, the literature is limited on the use and efficacy of antibiotic-eluding intramedullary dowels in periprosthetic joint infection. We reviewed the available literature and have found that the data at this point are equivocal with respect to whether antibiotic-impregnated cement intramedullary dowels augment the intra-articular antibiotic cement spacer in eradicating infection in total knee arthroplasty. Thus, we believe that the decision to use dowels can be left up to the surgeon preference. However, further research is warranted to review operative room efficiency and healthcare costs, and to validate the clinical efficacy of antibiotic-impregnated dowels in periprosthetic joint infection.

Do Antibiotic-Impregnated Intramedullary Dowels Assist in Eradicating Infection in Total Knee Arthroplasty? Pro

13-02-2020 – Brandon H. Naylor, Giles R. Scuderi

Journal Article

Antibiotic-loaded bone cement (ALBC) spacer constructs for the treatment of periprosthetic joint infections of the knee continue to evolve from the original hockey puck designs. Countless techniques have since been described for augmentation of ALBC spacers with the use of intramedullary (IM) dowels. The use of IM dowels has become a vital addition to any knee spacer construct. ALBC IM dowels are an excellent vessel to provide targeted local antibiotic treatment to high-risk areas like the medullary canal while increasing the overall therapeutic antibiotic elution. In addition, IM dowels provide needed stabilization to the relatively unstable intra-articular spacer component, thereby reducing spacer-related complications like displacement and fracture. Therefore, we recommend regular use of IM dowel augmentation to ALBC spacer constructs.

Point/Counterpoint: Nonarticulating vs Articulating Spacers for Resection Arthroplasty of the Knee or Hip

13-02-2020 – Cody C. Wyles, Matthew P. Abdel

Journal Article

Two-stage exchange arthroplasty remains the gold standard for chronic total knee arthroplasty (TKA) and total hip arthroplasty infections in North America. Cement spacers impregnated with high-dose antibiotics have been successfully used in the interim period of the 2-stage exchange process. A number of spacers have been described; however, this article will focus on articulating spacers. In the presence of an intact extensor mechanism (for TKA), reasonable soft tissue envelope, and adequate bone, articulating antibiotic spacers provide several advantages. These include an infection eradication rate of approximately 90%, higher range of motion after reimplantation, and lower complication rates when compared with nonarticulating spacers. In the appropriate patient, articulating antibiotic spacers are an effective and a safe treatment for infected TKAs and total hip arthroplasties.

Point/Counterpoint: Static vs Articulating Spacers—Static Spacers for Resection Arthroplasty of the Knee

13-02-2020 – Erik C. Bowman, Arthur L. Malkani

Journal Article

Antibiotic spacers play a significant role in the treatment of periprosthetic joint infections. They help maintain soft-tissue tension and provide delivery of high dose of antibiotics to the local tissue. The use of static or dynamic spacers is based on multiple factors including the extent of soft-tissue, ligamentous and bone compromise, overall patient function, comorbid conditions, and virulence of the organism. There is no difference in reinfection incidence between static vs dynamic spacers following two-stage reimplantation. Static spacers can be customized to treat all cases of periprosthetic total knee infections and offer intraoperative flexibility to vary the cement quantity and amount of antibiotics in the spacer to provide high-dose local delivery of antibiotics to address the dead space, bone loss, and soft-tissue compromise. Static spacers are especially advantageous in cases of extensor mechanism and ligamentous compromise where articulating spacers may not be able to provide adequate stability.

Spacer Design Options and Consideration for Periprosthetic Joint Infection

13-02-2020 – Scott M. Sporer

Journal Article

An articulating or nonarticulating antibiotic hip spacer can be placed following the first stage implant removal of a periprosthetic hip joint infection. Antibiotic spacers help fill in the dead space created at the time of resection and provide a high local concentration of antibiotics. Theoretical advantages of a static spacer include a higher elution of antibiotics because of the increased surface area, the ability to protect deficient bone in the proximal femur/acetabulum, and the ability to immobilize the periarticular soft tissues. Advantages of an articulating spacer include improved ambulation and easier motion for the patient, maintenance of soft tissue tension, and an easier surgical reconstruction at the time of the second stage. Additionally, an articulating antibiotic spacer may minimize the risk of dislocation following the second stage reconstruction. The choice of articulating or nonarticulating is currently one of surgeon preference yet it is advised that surgeons consider an articulating spacer for all patients except those with severe femoral/acetabular bone loss or deficient abductors.

Single vs 2-Stage Revision for the Treatment of Periprosthetic Joint Infection

13-02-2020 – Beau J. Kildow, Craig J. Della-Valle, Bryan D. Springer

Journal Article

Periprosthetic joint infection (PJI) is one of the most devastating complications following total joint arthroplasty, accounting for a projected 10,000 revision surgeries per year by 2030. Chronic PJI is complicated by the presence of bacterial biofilm, requiring removal of components, thorough debridement, and administration of antibiotics for effective eradication. Chronic PJI is currently managed with single-stage or 2-stage revision surgery. To date, there are no randomized, prospective studies available evaluating eradication rates and functional outcomes between the 2 techniques. In this review, both treatment options are described with the most current literature to guide effective surgical decision-making that is cost-effective while decreasing patient morbidity.

Antibiotic Choice: The Synergistic Effect of Single vs Dual Antibiotics

13-02-2020 – Nequesha S. Mohamed, Wayne A. Wilkie, Ethan A. Remily, James Nace, Ronald E. Delanois, James A. Browne

Journal Article

Introduction

This review summarizes single vs dual antibiotic cement literature, evaluating for synergistic activity with dual antibiotics.

Methods

A systematic review was performed for literature regarding dual antibiotics in cement, identifying 13 studies to include for review.

Results

Many in vitro studies reported higher elution from cement and/or improved bacteria inhibition with dual antibiotics, typically at higher dosages with a manual mixing technique. Limited clinical data from hip hemiarthroplasties and spacers demonstrated that dual antibiotics were associated with improved infection prevention and higher intra-articular antibiotic concentrations.

Conclusion

In addition to broader pathogen coverage, several studies document synergy of elution and increased antibacterial activity when dual antibiotics are added to cement. Limited clinical evidence suggests that dual antibiotic cement may be associated with reduced infection rates.

Surgical Options and Approaches for Septic Arthritis of the Native Hip and Knee Joint

13-02-2020 – Caleb M. Davis, Rodolfo A. Zamora

Journal Article

Septic arthritis (SA) of the adult knee and hip is a constantly evolving and urgent surgical issue. The epidemiology has shifted over the last few decades as have the most popular antibiotics and surgical treatments. SA of all types is increasing in the United States. There remains a high variability in the conservative and surgical management options available. This review will outline the most current understanding of the etiology and epidemiology of SA and will also discuss the distribution of causative organisms and appropriate treatments for each. A summary of evidence for different debridement and reconstructive techniques will also be presented in addition to novel areas of research to decrease the morbidity of this constantly growing problem.

Evolution of Diagnostic Definitions for Periprosthetic Joint Infection in Total Hip and Knee Arthroplasty

13-02-2020 – Jesus M. Villa, Tejbir S. Pannu, Nicolas Piuzzi, Aldo M. Riesgo, Carlos A. Higuera

Journal Article

Various definitions and biomarkers have been developed in an unsuccessful attempt to obtain a “gold standard” for periprosthetic joint infection (PJI) diagnosis. The development of the 2011 Musculoskeletal Infection Society criteria facilitated further research and advances by allowing the use of a consistent PJI definition across studies. The newly proposed 2018 criteria do not rely at all on expert opinions/consensus. In this review, we describe the most relevant definitions developed throughout recent time, their rationale, characteristics, and supportive evidence for their clinical implementation. In the opinion of the authors, the orthopedic community should consider a probability and likelihood paradigm to create a PJI diagnostic definition. Probably not a single definition might be suited for all situations; the inclusion of serological findings could be the next step moving forward.

Intraoperative and Postoperative Infection Prevention

13-02-2020 – Karan Goswami, Kimberley L. Stevenson, Javad Parvizi

Journal Article

Implementation of strategies for prevention of surgical site infection and periprosthetic joint infection is gaining further attention. We provide an overview of the pertinent evidence-based guidelines for infection prevention from the World Health Organization, the Centers for Disease Control and Prevention, and the second International Consensus Meeting on Musculoskeletal Infection. Future work is needed to ascertain clinical efficacy, optimal combinations, and the cost-effectiveness of certain measures.

Introduction

13-02-2020 – Michael A. Mont

Editorial