Spine

“Night Scene of Lujiazui, Shanghai”

01-03-2020 –

Journal Article

No abstract available

Improved Accuracy of Cervical Spinal Surgery With Robot-Assisted Screw Insertion: A Prospective, Randomized, Controlled Study

01-03-2020 – Fan, Mingxing; Liu, Yajun; He, Da; Han, Xiaoguang; Zhao, Jingwei; Duan, Fangfang; Liu, Bo; Tian, Wei

Journal Article

Study Design. Prospective, randomized, controlled trial.
Objective. To compare robot-assisted and conventional implantation techniques by evaluating the accuracy and safety of implanting screws in cervical vertebrae.
Summary of Background Data. Cervical spinal surgery is difficult and dangerous as screw misplacement might lead not only to decreased stability but also neurological, vascular, and visceral injuries. A new robot-assisted surgical procedure has been introduced to improve the accuracy of implant screw positioning.
Methods. We randomly assigned 135 patients with newly diagnosed cervical spinal disease and who required screw fixation using either robot-assisted or conventional fluoroscopy-assisted cervical spinal surgery. The primary outcomes were the discrepancies between the planned trajectories and the actual screw positions.
Results. Altogether, 127 patients underwent the assigned intervention (61 robot-assisted and 66 conventional fluoroscopy-assisted). The baseline characteristics including the screw types, were similar in the two groups. Altogether, 390 screws were planed and placed in the cervical vertebrae, and 94.9% were acceptable. The robot-assisted group had a better screw placement accuracy than the conventional fluoroscopy-assisted group with associated P values <0.001 (0.83 0.44, 1.29 vs. 1.79 1.41, 2.50 mm). The Gertzbein and Robbins scales also showed a significant difference between the two groups (P < 0.001). Furthermore, the robot-assisted group experienced significantly less blood loss during surgery than the conventional fluoroscopy-assisted group (200 50, 375 vs. 350 100, 500 m
L; P = 0.002) and shorter length of stay after surgery (P = 0.021). These two groups did not differ significantly regarding the duration of the operation (P = 0.525). Neurological injury occurred in one case in the conventional fluoroscopy-assisted group.
Conclusion. The accuracy and clinical outcomes of cervical spinal surgery using the robot-assisted technique tended to be superior to those with the conventional fluoroscopy-assisted technique in this prospective, randomized, controlled trial.
Level of Evidence: 2

17β-Estradiol Prevents Extracellular Matrix Degradation by Downregulating MMP3 Expression via PI3K/Akt/FOXO3 Pathway

01-03-2020 – Gao, Xiao-Wen; Su, Xiao-Tao; Lu, Zheng-Hao; Ou, Jun

Journal Article

Study Design. In vitro studies of the role of 17β-estradiol (E2) and its possible targets in intervertebral disc degeneration (IDD).
Objective. To define the regulatory role of E2 in IDD and the potential mechanisms.
Summary of Background Data. IDD has intricate etiology that is influenced by multiple risk factors. However, the underlying molecular mechanisms of occurrence and progression of IDD are not well elucidated. The degradation of extracellular matrix (ECM) has been extensively observed in IDD. E2 was found to inhibit ECM degradation in human nuleus pulposus cells (HNPCs), but the molecular mechanism remained to be determined.
Methods. Western blot and q
PCR was performed to quantify the expression of target proteins in HNPCs. Luciferase reporter gene assay was applied to detect the effects of E2 and forkhead box O-3 (FOXO3) on matrix metalloproteinases (MMP)-3 promoter activity. Chromatin immunoprecipitation assay analyzed the binding of FOXO3 to MMP-3 and the effect of E2 on this process.
Results. We identified the upregulation of collagen II and aggrecan by E2 independent of time and concentration. And E2 downregulated MMP-3 expression in human nucleus pulposus cells. The phosphorylation of FOXO3 led to the reduction of MMP-3 promoter activity. Furthermore, 17β-estradiol-induced the activation of PI3K/Akt pathway is required for FOXO3 phosphorylated.
Conclusion. E2 prevents the degradation of ECM by upregulating collagen II and aggrecan expression via reducing MMP-3 expression in HNPCs, and PI3K/Akt/FOXO3 pathway is dispensable for MMP-3 downregulated. Therefore, E2 protects against IDD by preventing ECM degradation.
Level of Evidence: 3

Lumbar Axial Rotation Kinematics in an Upright Sitting and With Forward Bending Positions in Men With Nonspecific Chronic Low Back Pain

01-03-2020 – Masharawi, Youssef; Haj, Alaa; Weisman, Asaf

Journal Article

Study Design. A controlled cross-sectional study.
Objective. The aim of this study was to compare the kinematics of lumbar axial rotation while sitting in an upright and forward bending position in men suffering with and without nonspecific chronic low back pain (NSCLBP).
Summary of Background Data. Lumbar rotation while sitting is an important factor in the mechanism of low back pain. Nevertheless, its kinematics has scarcely been investigated.
Methods. Range of motion (ROM in), average velocity (AV), maximum velocity (MV), and maximal acceleration (MA) of lumbar rotation while sitting in an upright (UP-sitting) and full forward bending position (FFB-sitting) were examined using an industrial lumbar motion monitor in 50 men (25 with NSCLBP and 25 controls). Pain level and the Rolland Morris questionnaire (RMQ) were also included.
Results. All examined kinematical parameters were significantly lower in men with NSCLBP compared with the controls (↓ROM = 16%–29%; ↓AV = 35%–53%; ↓MV = 3%–46%; ↓MA = 7%–44%) and significantly decreased when moving from UP-sitting to FFB-sitting. In the UP-sitting, the ROM and AV in both groups and the right rotation-MV in the NSCLBP group were always greater during the right rotation compared to the left (NSCLBP = ROM: Δ3.92°, AV: Δ2.74°/s, MV:Δ3.61°/s; controls = ROM: Δ3.46°, AV: Δ1.72°/s). The left rotation-MV was significantly greater compared to the right only in FFB-sitting in the controls (Δ3.03°/s). In all kinematical parameters in the NSCLBP group, no correlations were found in the visual analogue scale (VAS) levels (4.43 ± 1.47) or RMQ total score (12.32 ± 5.44).
Conclusion. The kinematic parameters of lumbar rotation were reduced in men with NSCLBP compared with controls both in an UP-sitting and FFB-sitting. In both groups, NSCLBP and controls, asymmetry in lumbar rotation kinematics was indicated as well as a decrease when moving from UP-sitting to FFB-sitting.
Level of Evidence: 3

Rib Hyperostosis as a Risk Factor for Poor Prognosis in Cervical Spine Injury Patients With Diffuse Idiopathic Skeletal Hyperostosis

01-03-2020 – Sawakami, Kimihiko; Watanabe, Kei; Sato, Tsuyoshi; Miura, Kazuto; Katsumi, Keiichi; Hosaka, Noboru; Nomura, Shinsen; Fujikawa, Ryuta; Kikuchi, Ren; Tashi, Hideki; Minato, Keitaro; Segawa, Hiroyuki; Ito, Takui; Ishikawa, Seiichi; Hirano, Toru; Endo, Naoto

Journal Article

Study Design. Retrospective multi-center study.
Objective. To identify the morphological features of costovertebral joints and ribs in surgically managed cervical injury patients with diffuse idiopathic skeletal hyperostosis (DISH) and to examine its impact on their vital prognosis.
Summary of Background Data. Several reports have indicated that DISH is an independent risk factor for mortality after spinal fracture. The reason for the high mortality in cervical injury patients with DISH is unclear, although some reports have suggested a possible association between pulmonary complications and mortality.
Methods. From 1999 to 2017, a total of 50 DISH patients (44 males) with cervical spine injuries who underwent spinal surgery were enrolled (average age 74 yrs). Prognosis and clinical risk factor data were collected; the morphological features of the patients’ costovertebral joints and ribs were evaluated with computed tomography. The influence of each proposed risk factor and thoracic morphological feature on mortality was tested with univariate and multivariate analyses.
Results. The survival rate at 5 years after surgery was 52.3%. Nineteen (38%) patients died, and the most common cause of death was pneumonia (68%). Costovertebral bone excrescences and rib hyperostosis were found to be thoracic pathognomonic signs; their frequencies were 94% and 82%, respectively, and these conditions occurred in an average of 7.0 joints and 4.7 bones, respectively. The results of the log-rank test showed a significant difference in age, injury severity score (ISS), costovertebral bone excrescences, and rib hyperostosis. The results of age-adjusted multivariate analysis indicated that age (hazard ratio HR = 8.65, 95% confidence interval CI = 1.10–68.28, P = 0.041) and rib hyperostosis (HR = 3.82, 95% CI = 1.38–10.57, P = 0.010) were associated with mortality.
Conclusion. Reduced chest wall mobility associated with rib hyperostosis in cervical spine injury patients with DISH leads to a poor prognosis.
Level of Evidence: 3

Selecting the Last Substantially Touching Vertebra as Lowest Instrumented Vertebra in Lenke type 2A-R and 2A-L Curves

01-03-2020 – Qin, Xiaodong; He, Zhong; Yin, Rui; Qiu, Yong; Zhu, Zezhang

Study Design. A retrospective study.
Objective. The aim of this study was to determine whether the last substantially touching vertebra (LSTV) can be selected as the optimal lowest instrumented vertebra (LIV) for Lenke 2A adolescent idiopathic scoliosis (AIS) with different lumbar modifiers (2A-R and 2A-L) and to investigate its relationship with the distal adding-on.
Summary of Background Data. Previous studies have documented good outcomes in Lenke 1A curve when LSTV was selected as LIV.
Methods. A total of 101 female patients were included with a minimum of 2-year follow-up after selective posterior surgery. Patients were classified on the basis of the direction of L4 tilt: 2A-L and 2A-R. Patients with LSTV-1, LSTV, or LSTV+1 selected as LIV were assigned to three groups. Factors associated with adding-on were analyzed through comparison among the three groups.
Results. The level of LSTV was more distal in the 2A-R group than that in the 2A-L group (P = 0.011). Distal adding-on was observed in 24 patients (23.8%). In the 2A-R curves, 26.1% patients were found to have adding-on. The incidence of adding-on was significantly higher in LSTV-1 than LSTV or LSTV+1 group. Logistic regression analysis showed the distance between LIV and LSTV (LIV-LSTV <0) was the independent factor associated with adding-on (odds ratio OR = 8.7, 95% confidence interval CI = 3.1–45.5, P = 0.011). In the 2A-L curves, 21.8% patients were found to have adding-on. The incidence of adding-on was significantly lower in LSTV+1 than LSTV-1 or LSTV group. Similarly, logistic regression showed the distance between LIV and LSTV (LIV-LSTV ≤0) had significant association with adding-on (OR = 11.9, 95% CI = 2.5–53.2, P = 0.009).
Conclusion. The distance between LIV and LSTV was a significant factor associated with adding-on for both 2A-R and 2A-L patients. The rule of selecting LIV should be different between 2A-R and 2A-L curves. We recommend to extend the fusion level to LSTV in 2A-R curve and to LSTV+1 in 2A-L curve to avoid distal adding-on.
Level of Evidence: 3

Utilization of Predictive Modeling to Determine Episode of Care Costs and to Accurately Identify Catastrophic Cost Nonwarranty Outlier Patients in Adult Spinal Deformity Surgery: A Step Toward Bundled Payments and Risk Sharing

01-03-2020 – Ames, Christopher P.; Smith, Justin S.; Gum, Jeffrey L.; Kelly, Michael; Vila-Casademunt, Alba; Burton, Douglas C.; Hostin, Richard; Yeramaneni, Samrat; Lafage, Virginie; Schwab, Frank J.; Shaffrey, Christopher I.; Bess, Shay; Pellisé, Ferran; Serra-Burriel, Miquel; on behalf of the European Spine Study Group and International Spine Study Group

Journal Article

Study Design. Retrospective review of prospectively-collected, multicenter adult spinal deformity (ASD) database.
Objective. The aim of this study was to evaluate the rate of patients who accrue catastrophic cost (CC) with ASD surgery utilizing direct, actual costs, and determine the feasibility of predicting these outliers.
Summary of Background Data. Cost outliers or surgeries resulting in CC are a major concern for ASD surgery as some question the sustainability of these surgical treatments.
Methods. Generalized linear regression models were used to explain the determinants of direct costs. Regression tree and random forest models were used to predict which patients would have CC (>$100,000).
Results. A total of 210 ASD patients were included (mean age of 59.3 years, 83% women). The mean index episode of care direct cost was $70,766 (SD = $24,422). By 90 days and 2 years following surgery, mean direct costs increased to $74,073 and $77,765, respectively. Within 90 days of the index surgery, 11 (5.2%) patients underwent 13 revisions procedures, and by 2 years, 26 (12.4%) patients had undergone 36 revision procedures. The CC threshold at the index surgery and 90-day and 2-year follow-up time points was exceeded by 11.9%, 14.8%, and 19.1% of patients, respectively. Top predictors of cost included number of levels fused, surgeon, surgical approach, interbody fusion (IBF), and length of hospital stay (LOS). At 90 days and 2 years, a total of 80.6% and 64.0% of variance in direct cost, respectively, was explained in the generalized linear regression models. Predictors of CC were number of fused levels, surgical approach, surgeon, IBF, and LOS.
Conclusion. The present study demonstrates that direct cost in ASD surgery can be accurately predicted. Collectively, these findings may not only prove useful for bundled care initiatives, but also may provide insight into means to reduce and better predict cost of ASD surgery outside of bundled payment plans.
Level of Evidence: 3

A Practical Study of Diagnostic Accuracy: Scoliosis Screenings of Middle School Students by a Trained Nurse With a Smartphone Versus a Spine Surgeon With a Scoliometer

01-03-2020 – Chen, Chao; Yu, Ronghua; Xu, Wei; Li, Zhikun; Li, Yifan; Hu, Ruixi; Zhu, Xiaodong

Journal Article

Study Design. Cross-sectional.
Objective. This study aimed to assess the accuracy of smartphone-aided diagnosis of scoliosis by a trained nurse compared with scoliometer-based diagnosis by a spine surgeon.
Summary of Background Data. Many assessments have been developed to estimate the reliability of smartphone-aided measurements in diagnosing scoliosis. However, clinical studies assessing the accuracy of smartphone-aided diagnosis with radiographs or scoliometers are scarce.
Methods. A total of 2702 grade 7 students (mean age 13.56 yrs, range 13–15) at 10 middle schools were first screened with a smartphone by a trained nurse from the orthopedics department. Approximately half a year later, most of the students underwent a chest x-ray examination as part of a compulsory medical examination. Students with suspicious findings in either the first screen or the chest x-ray were recommended to a scoliosis clinic for single-blind tests, such as a forward bending test (FBT) and an analysis of the angle of trunk rotation (ATR) with a scoliometer, performed by an experienced spine surgeon. Finally, the Cobb method was conducted with full-spine radiographs to serve as the gold standard.
Results. The agreement between the first screening by the nurse and the second test by the spine surgeon was low in cases with a Cobb angle 10° (κ = 0.349 0.19–0.50, P < 0.001). The results of receiver operating characteristic (ROC) curve analysis also suggested that these two tests were similar in their ability to diagnose scoliosis. However, when the Cobb angle cutoff was adjusted to 15°, the latter had markedly better diagnostic ability than the former. Overall, the sensitivity of the smartphone screening was not acceptable for recognizing scoliosis.
Conclusion. This study revealed that smartphone-aided screening for scoliosis is risky.
Level of Evidence: 3

Functional Connectivity Changes of the Visual Cortex in the Cervical Spondylotic Myelopathy Patients: A Resting-State fMRI Study

01-03-2020 – Chen, Zhao; Zhao, Rui; Wang, Qiu; Yu, Chunshui; Li, Fengtan; Liang, Meng; Zong, Yaqi; Zhao, Ying; Xiong, Wuyi; Su, Zhe; Xue, Yuan

Journal Article

Study Design. Cross-sectional study.
Objective To analyze altered functional connectivity (FC) in the visual cortex of cervical spondylotic myelopathy (CSM) patients using resting-state functional magnetic resonance imaging (f
MRI).
Summary of Background Data. We previously showed changes in visual cortex neural activity in CSM patients.
Methods. Thirty CSM patients and 20 healthy controls were recruited. MR data were collected using a 3.0 T MR. FC of the regions of interest (ROI) (Brodmann areas BA 17/18/19/7) were calculated in a voxel-wise manner and compared between groups. Correlation analyses were performed between preoperative Japanese Orthopaedic Association (JOA) scores and altered FC, as well as between preoperative best corrected visual acuity (BCVA) and altered FC. Furthermore, the FC where was compared between the preoperative and the postoperative CSM patients in an ROI-wise manner.
Results. Increased FC was found between BA19 and the cerebellum inferior lobe; between the left BA7 and bilateral calcarine, right lingual, right fusiform gyrus, and left precuneus (BA17); between the left BA7 and right fusiform gyrus and right inferior occipital gyrus (right BA19); and between the right BA7 and right superior lobe of cerebellum (right BA19) in CSM patients (P < 0.05). A negative correlation was found between JOA score and FC of the left and right BA19, and a positive correlation was found between the BCVA and FC of the left and right BA7 (P < 0.05). ROI analysis demonstrated statistically significant FC differences in between the preoperative and the postoperative CSM patients (P < 0.05).
Conclusion. FC changes were present in the visual cortex of CSM patients, which negatively correlated with preoperative JOA scores and positively correlated with preoperative BCVA. Significant recovery of FC in the visual cortex was detected in CSM patients postoperatively.
Level of Evidence: 4

Association Between Excessive Weight Gain During Pregnancy and Persistent Low Back and Pelvic Pain After Delivery

01-03-2020 – Matsuda, Naoka; Kitagaki, Kazufumi; Perrein, Emeline; Tsuboi, Yamato; Ebina, Aoi; Kondo, Yuki; Murata, Shunsuke; Isa, Tsunenori; Okumura, Maho; Kawaharada, Rika; Horibe, Kana; Ono, Rei

Journal Article

Study Design. Retrospective study.
Objective. To investigate the association between gestational weight gain (GWG) during pregnancy and persistent low back and pelvic pain (LBPP) after delivery.
Summary of Background Data. Persistent LBPP after delivery is a risk factor for developing depression and chronic pain as well as incurring sick leave. Women experience weight gain during pregnancy. Excessive weight gain places a greater burden on the musculoskeletal system. However, little is known about how GWG is associated with LBPP after delivery.
Methods. After Ethics Committee approval, we analyzed 330 women at 4 months after delivery who had LBPP during pregnancy. The exclusion criteria were as follows: specific low back pain, multiple birth, and incomplete data. Four months after delivery, LBPP was assessed using a self-report questionnaire. Persistent LBPP was defined as pain at 4 months after delivery with an onset during pregnancy or within 3 weeks after delivery. GWG was calculated as the difference between the pregnancy weight and the prepregnancy weight, which we categorized into three groups: <10, 10 to <15, and ≥15 kg. Other confounding factors including age, height, weight at 4 months after delivery, parity, gestational week, mode of delivery, weight of the fetus, and prepregnancy LBPP were assessed. We used logistic regression analysis to calculate LBPP odds ratios (ORs) according to GWG.
Results. The prevalence of persistent LBPP was 34.1% (n = 113). Compared with women with a GWG of <10 kg, women with a GWG of ≥15 kg had a higher prevalence of persistent LBPP (OR = 2.77, 95% confidence interval (95% CI) = 1.28–5.96, adjusted OR = 2.35, 95% CI = 1.06–5.21); however, no significant difference was found for women with a GWG of 10 to <15 kg (OR = 1.18, 95% CI = 0.72–1.92, adjusted OR = 1.02, 95% CI = 0.61–1.72).
Conclusions. Our study showed that excessive weight gain during pregnancy is one of the risk factors of persistent LBPP. Appropriate weight control during pregnancy could help prevent persistent LBPP after delivery.
Level of Evidence: 3

Mortality and Cause of Death in Patients With Vertebral Fractures: A Longitudinal Follow-Up Study Using a National Sample Cohort

01-03-2020 – Choi, Hyo Geun; Lee, Joon Kyu; Sim, Songyong; Kim, Miyoung

Journal Article

Study Design. A retrospective study using the Korean Health Insurance Review and Assessment Service—National Sample Cohort was performed.
Objective. To determine the rate and causes of mortality in vertebral fracture patients.
Summary of Background Data. Vertebral fractures are associated with increased mortality in prior studies.
Methods. Of 1,125,691 patients, we collected data of 23,026 patients of all ages who experienced thoracic or lumber vertebral fractures between 2002 and 2013. The vertebral fracture participants were matched 1:4 with control participants, accounting for age, group, sex, income, and region of residence. Finally, 21,759 vertebral fracture participants and 87,036 control participants were analyzed. The index date was the date of diagnosis of vertebral fracture; participants from the control group were followed from the same index date as their matched counterparts. The follow-up duration was the index date to the death date or the last date of study (December 31, 2013). Patients were followed until death or censoring of the data. Death was ascertained in the same period, and causes of death were grouped into 12 classifications according to the Korean Standard Classification of Disease. A stratified Cox proportional hazards model was used.
Results. The adjusted hazard ratio (HR) for mortality of vertebral fracture was 1.28 (P < 0.001) with the higher adjusted HR in younger patients. Mortalities caused by neoplasms; neurologic, circulatory, respiratory, digestive, and muscular diseases; and trauma were higher in the vertebral fracture group (P < 0.05), with muscular disease showing the highest odds ratio for mortality.
Conclusion. Vertebral fractures were associated with increased mortality in Korean. Disease in muscuoskeletal system and connective tissue that possibly be associated with the fractures was most responsible for elevated death rates following vertebral fracture. Our findings may help caregivers provide more effective care, ultimately decreasing the mortality rate of vertebral fracture patients.
Level of Evidence: 3

Decompression With or Without Fusion for Lumbar Stenosis: A Cost Minimization Analysis

01-03-2020 – Ziino, Chason; Mertz, Kevin; Hu, Serena; Kamal, Robin

Study Design. Retrospective database review.
Objective. Compare 1-year episode of care costs between single-level decompression and decompression plus fusion for lumbar stenosis.
Summary of Background Data. Lumbar stenosis is the most common indication for surgery in patients over 65. Medicare direct hospital costs for lumbar surgery reached $1.65 billion in 2007. Despite stenosis being a common indication for surgery, there is debate as to the preferred surgical treatment. Cost-minimization analysis is a framework that identifies potential cost savings between treatment options that have similar outcomes. We performed a cost-minimization analysis of decompression versus decompression with fusion for lumbar stenosis from the payer perspective.
Methods. An administrative claims database of privately insured patients (Humana) identified patients who underwent decompression (n = 5349) or decompression with fusion (n = 8540) for lumbar stenosis with and without spondylolisthesis and compared overall costs. All patients were identified and costs identified for a 1-year period. Complication rates and costs were described using summary statistics.
Results. Mean treatment costs at 1 year after surgery were higher for patients who underwent decompression and fusion compared to patients who underwent decompression alone ($20,892 for fusion vs. $6329 for decompression; P < 0.001). Facility costs (P < 0.001), surgeon costs (P < 0.001), and physical therapy costs (P < 0.001) were higher in the fusion group. Cost differences related to infection or durotomy reached significance (P < 0.04). No difference in cost was identified for supplies.
Conclusion. Decompression had significantly lower costs for the treatment of lumbar stenosis, including treatment for postoperative complications. If cost minimization is the primary goal, decompression is favored for surgical treatment of lumbar stenosis. Other factors including shared decision-making directed toward patients values, patient-reported outcomes, and preferences should also be recognized as drivers of healthcare decisions.
Level of Evidence: 3

American Society of Anesthesiologists’ Status Association With Cost and Length of Stay in Lumbar Laminectomy and Fusion: Results From an Institutional Database

01-03-2020 – Bronheim, Rachel S.; Caridi, John M.; Steinberger, Jeremy; Hunter, Samuel; Neifert, Sean N.; Deutsch, Brian C.; DeMaria, Samuel Jr.; Hermann, Luke; Gal, Jonathan S.

Journal Article

Study Design. Retrospective cohort study.
Objective. The objective of this study was to characterize the costs associated with American Society of Anesthesiologists (ASA) class, and to determine the extent to which ASA status is a predictor of increased cost and LOS following lumbar laminectomy and fusion (LLF).
Summary of Background Data. Spinal fusion accounts for the highest hospital costs of any surgical procedure performed in the United States, and ASA (American Society of Anesthesiologists) status is a known risk factor for cost and length of stay (LOS) in the orthopedic literature. There is a paucity of literature that directly addresses the influence of ASA status on cost and LOS following LLF.
Methods. This is a retrospective cohort study of an institutional database of patients undergoing single-level LLF at an academic tertiary care facility from 2006 to 2016. Univariate comparisons were made using χ2 tests for categorical variables and t tests for continuous variables. Multivariate linear regression was utilized to estimate regression coefficients, and to determine whether ASA status is an independent risk factor for cost and LOS.
Results. A total of 1849 patients met inclusion criteria. For every one-point increase in ASA score, intensive care unit (ICU) LOS increased by 0.518 days (P < 0.001), and hospital length of stay increased by 1.93 days (P < 0.001). For every one-point increase in ASA score, direct cost increased by $7474.62 (P < 0.001).
Conclusion. ASA status is a predictor of hospital LOS, ICU LOS, and direct cost. Consideration of the ways in which ASA status contributes to increased cost and prolonged LOS can allow for more accurate reimbursement adjustment and more precise targeting of efficiency and cost effectiveness initiatives.
Level of Evidence: 3

Adult Spinal Deformity Surgery in Patients With Movement Disorders: A Propensity-matched Analysis of Outcomes and Cost

01-03-2020 – Varshneya, Kunal; Azad, Tej D.; Pendharkar, Arjun V.; Desai, Atman; Cheng, Ivan; Karikari, Isaac; Ratliff, John K.; Veeravagu, Anand

Study Design. This was a retrospective study using national administrative data from the Market
Scan database.
Objective. To investigate the complication rates, quality outcomes, and costs in a nationwide cohort of patients with movement disorders (MD) who undergo spinal deformity surgery.
Summary of Background Data. Patients with MD often present with spinal deformities, but their tolerance for surgical intervention is unknown.
Methods. The Market
Scan administrative claims database was queried to identify adult patients with MD who underwent spinal deformity surgery. A propensity-score match was conducted to create two uniform cohorts and mitigate interpopulation confounders. Perioperative complication rates, 90-day postoperative outcomes, and total costs were compared between patients with MD and controls.
Results. A total of 316 patients with MD (1.7%) were identified from the 18,970 undergoing spinal deformity surgery. The complication rate for MD patients was 44.6% and for the controls 35.6% (P = 0.009). The two most common perioperative complications were more likely to occur in MD patients, acute-posthemorrhagic anemia (26.9% vs. 20.8%, P < 0.05) and deficiency anemia (15.5% vs. 8.5%, P < 0.05). At 90 days, MD patients were more likely to be readmitted (17.4% vs. 13.2%, P < 0.05) and have a higher total cost ($94,672 vs. $85,190, P < 0.05). After propensity-score match, the overall complication rate remained higher in the MD group (44.6% vs. 37.6%, P < 0.05). 90-day readmissions and costs also remained significantly higher in the MD cohort. Multivariate modeling revealed MD was an independent predictor of postoperative complication and inpatient readmission. Subgroup analysis revealed that Parkinson disease was an independent predictor of inpatient readmission, reoperation, and increased length of stay.
Conclusion. Patients with MD who undergo spinal deformity surgery may be at risk of higher rate of perioperative complications and 90-day readmissions compared with patients without these disorders.
Level of Evidence: 3

Profile of Patients With Acute Low Back Pain Who Sought Emergency Departments: A Cross-sectional Study

01-03-2020 – Oliveira, Indiara Soares; Vanin, Adriane Aver; Pena Costa, Leonardo Oliveira; Medeiros, Flávia Cordeiro; Ananias Oshima, Renan Kendy; Inácio, Angela Augusto; Matos da Cunha, Thayane Araújo; Palomo, Andressa Santos; Fukuda, Thiago Yukio; de Freitas, Diego Galace; Benvenuto, Fernando; Menezes Costa, Lucíola da Cunha

Study Design. A cross-sectional study.
Objective. The aim of this study is to describe the profile of patients with acute low back pain (LBP) who sought emergency departments (EDs) in Brazilian public hospitals. We also described the profile of these patients according to the STar
T Back Screening Tool (SBST).
Summary of Background Data. LBP is the most common musculoskeletal condition worldwide and is one of the main complaints in EDs. There is a lack of evidence describing the profile of these patients from low- to middle-income countries.
Methods. This is a cross-sectional study involving patients with a new episode of nonspecific acute LBP that was conducted between August 2014 and August 2016. Variables related to clinical, psychological, sociodemographic and work status characteristics were investigated through structured, in-person oral questionnaire.
Results. A total of 600 patients were included in the study. The majority of the patients were women (58%), with a median of eight points on pain intensity (measured on an 11-point scale) and 17 points on disability (measured on a 24-item questionnaire). With regards to the SBST evaluation, 295 (49.2%) patients were classified as being at high risk of developing an unfavorable prognosis with a median pain intensity of nine points on pain intensity, 20 points on disability, and seven points on depression (measured on an 11-point scale). Despite this, the majority of the patients (74%) continued working normally without interference from LBP.
Conclusion. Identifying the profile of patients seeking care in EDs can help to define effective management for LBP in low- and middle-income countries. Patients with nonspecific acute LBP who seek EDs in Brazil present high levels of pain intensity and disability. Most patients were classified as having a high risk of developing an unfavorable prognosis.
Level of Evidence: 2

Spinal Fusion Surgery and Local Antibiotic Administration: A Systematic Review on Key Points From Preclinical and Clinical Data

01-03-2020 – Maria, Sartori; Deyanira, Contartese; Francesca, Salamanna; Lucia, Martini; Alessandro, Ricci; Silvia, Terzi; Alessandro, Gasbarrini; Milena, Fini

Journal Article

Study Design. Systematic review.
Objective. The present review of clinical and preclinical in vivo studies focused on the local antibiotic administration for surgical site infection (SSI) in spinal fusion procedures and identifying new approaches or research direction able to release antibiotics in the infected environment.
Summary of Background Data. SSI is a severe complication of spinal fusion procedures that represents a challenging issue for orthopedic surgeons. SSIs can range from 0.7% to 2.3% without instrumentation up to 6.7% with the use of instrumentation with significant implications in health care costs and patient management.
Method. A systematic search was carried out by two independent researchers according to the PRISMA statement in three databases (www.pubmed.com, www.scopus.com and www.webofknowledge.com) to identify preclinical in vivo and clinical reports in the last 10 years. Additionally, to evaluate ongoing clinical trials, three of the major clinical registry websites were also checked (www.clinicaltrials.gov, www.who.int/ictrp, https://www.clinicaltrialsregister.eu).
Results. After screening, a total of 43 articles were considered eligible for the review: 36 clinical studies and seven preclinical studies. In addition, six clinical trials were selected from the clinical registry websites.
Conclusion. The results reported that the topical vancomycin application seem to represent a strategy to reduce SSI incidence in spine surgery. However, the use of local vancomycin as a preventive approach for SSIs in spine surgery is mostly based on retrospective studies with low levels of evidence and moderate/severe risk of bias that do not allow to draw a clear conclusion. This review also underlines that several key points concerning the local use of antibiotics in spinal fusion still remains to be defined to allow this field to make a leap forward that would lead to the identification of specific approaches to counteract the onset of SSIs.
Level of Evidence: 4

High, As Well As Low, Preoperative Platelet Counts Correlate With Adverse Outcomes After Elective Posterior Lumbar Surgery

01-03-2020 – Malpani, Rohil; Gala, Raj J.; Adrados, Murillo; Galivanche, Anoop R.; Clark, Michael G.; Mercier, Michael R.; Pathak, Neil; Mets, Elbert J.; Grauer, Jonathan N.

Study Design. Retrospective cohort study of prospectively collected data.
Objective. Assess correlation between preoperative platelet counts and postoperative adverse events after elective posterior lumbar surgery procedures.
Summary of Background Data. Preoperative low platelet counts have been correlated with adverse outcomes after posterior lumbar surgery. Nonetheless, the effect of varying platelet counts has not been studied in detail for a large patient population, especially on the high end of the platelet spectrum.
Methods. Patients who underwent elective posterior lumbar surgery were identified in the 2011 to 2016 National Surgical Quality Improvement Program database. Preoperative platelet counts were considered relative to 30-day perioperative adverse outcomes. Patients were classified into platelet categories based on determining upper and lower bounds on when the adverse outcomes crossed a relative risk of 1.5. Univariate and multivariate analyses compared 30-day postoperative complications, readmissions, operative time, and hospital length of stay between those with low, normal, and high platelet counts.
Results. In total, 137,709 posterior lumbar surgery patients were identified. Using the relative risk threshold of 1.5 for the occurrence of any adverse event, patients were divided into abnormally low (≤140,000/m
L) and abnormally high (≥447,000/m
L) platelet cohorts. The abnormally low and high platelet groups were associated with higher rates of any, major, minor adverse events, transfusion, and longer hospital length of stay. Furthermore, the abnormally low platelet counts were associated with a higher risk of readmissions.
Conclusion. The data-based cut-offs for abnormally high and low platelet counts closely mirrored those found in literature. Based on these definitions, abnormally high and low preoperative platelet counts were associated with adverse outcomes after elective posterior lumbar surgery. These findings facilitate risk stratification and suggest targeted consideration for patients with high, as well as low, preoperative platelet counts.
Level of Evidence: 3

To the Editor:

01-03-2020 – Le, Xiaofeng; Hao, Dingjun

Journal Article

No abstract available