Hip Arthroscopy Simulator Training With Immersive Virtual Reality Has Similar Effectiveness to Nonimmersive Virtual Reality.

PURPOSE: To (1) compare the efficacy of immersive virtual reality (iVR) to nonimmersive virtual reality (non-iVR) training in hip arthroscopy on procedural and knowledge-based skills acquisition and (2) evaluate the relative cost of each platform. METHODS: Fourteen orthopaedic surgery residents were randomized to simulation training utilizing an iVR Hip Arthroscopy Simulator (n = 7; PrecisionOS) or non-iVR simulator (n = 7; ArthroS Hip VR; VirtaMed). After training, performance was assessed on a cadaver by 4 expert hip arthroscopists through arthroscopic video review of a diagnostic hip arthroscopy. Performance was assessed using the Objective Structured Assessment of Technical Skills (OSATS) and Arthroscopic Surgery Skill Evaluation Tool (ASSET) scores. A cost analysis was performed using the transfer effectiveness ratio (TER) and a direct cost comparison of iVR to non-iVR. RESULTS: Demographic characteristics did not differ between treatment arms or by training level, hip arthroscopy experience, or prior simulator use. No significant differences were observed in OSATS and ASSET scores between iVR and non-iVR cohorts (OSATS: iVR 19.6 ± 4.4, non-iVR 21.0 ± 4.1, P = .55; ASSET: iVR 23.7 ± 4.5, non-iVR 25.8 ± 4.8, P = .43). The absolute TER was 0.06 and there was a 132-fold cost difference of iVR to non-iVR. CONCLUSIONS: Hip arthroscopy simulator training with iVR had similar performance results to non-iVR for technical skill and procedural knowledge acquisition after expert arthroscopic video assessment. The iVR platform had similar effectiveness in transfer of skill compared to non-iVR with a 132 times cost differential. CLINICAL RELEVANCE: Due to the accessibility, effectiveness, and relative affordability, iVR training may be beneficial in the future of safe arthroscopic hip training.

Assessment and Trends of the Methodological Quality of the Top 50 Most Cited Articles on Patellar Instability.

BACKGROUND: Studies with a low level of evidence (LOE) have dominated the top cited research in many areas of orthopaedics. The wide range of treatment options for patellar instability necessitates an investigation to determine the types of studies that drive clinical practice. PURPOSE: To determine (1) the top 50 most cited articles on patellar instability and (2) the correlation between the number of citations and LOE or methodological quality. STUDY DESIGN: Cross-sectional study. METHODS: The Scopus and Web of Science databases were assessed to determine the top 50 most cited articles on patellar instability between 1985 and 2019. Bibliographic information, number of citations, and LOE were collected. Methodological quality was calculated using the Modified Coleman Methodology Score (MCMS) and the Methodological Index for Non-Randomized Studies (MINORS). Mean citations and mean citation density (citations per year) were correlated with LOE, MCMS, and MINORS scores. RESULTS: Most studies were cadaveric (n = 10; 20.0%), published in the American Journal of Sports Medicine (n = 13; 26.0%), published between 2000 and 2009 (n = 41; 82.0%), and conducted in the United States (n = 17; 34.0%). The mean number of citations and the citation density were 158.61 ± 59.53 (range, 95.5-400.5) and 12.74 ± 5.12, respectively. The mean MCMS and MINORS scores were 59.62 ± 12.58 and 16.24 ± 3.72, respectively. No correlation was seen between mean number of citations or citation density versus LOE. A significant difference was found in the mean LOE of articles published between 1990 and 1999 (5.0 ± 0) versus those published between 2000 and 2009 (3.12 ± 1.38; P = .03) and between 2010 and 2019 (3.00 ± 1.10; P = .01). CONCLUSION: There was a shift in research from anatomy toward outcomes in patellar instability; however, these articles demonstrated low LOE and methodological quality. Higher quality studies are necessary to establish informed standards of management of patellar instability.

Timeline for maximal subjective outcome improvement following total ankle arthroplasty.

BACKGROUND: Maximal medical improvement (MMI) establishes the timepoint when patients no longer experience clinically significant improvements following surgery. The purpose of this investigation is to establish when patients achieve MMI following total ankle arthroplasty (TAA) through the use of patient reported outcome measures (PROMs). METHODS: A systematic review to identify studies on TAA which reported consecutive PROMs for two years postoperatively was performed. Pooled analysis was done at 6 months, 12 months, and 24 months. Clinically significant improvement was defined as improvement between time intervals exceeding the minimal clinically important difference. RESULTS: Twelve studies and 1514 patients met inclusion criteria. Clinically significant improvement was seen up to 6 months postoperatively in both the American Orthopaedic Foot and Ankle Society Ankle Hindfoot Score and Visual Analog Scale scoring systems. The Short Musculoskeletal Function Assessment Dysfunction and Bother subsections showed maximal clinically significant improvement by 1 year postoperatively. CONCLUSION: Following TAA, MMI is seen by one year postoperatively. Physicians may allocate the majority of resources within the first year when most of the improvement is perceived. This data may help inform preoperative counseling as it establishes a timeline for MMI. LEVEL OF EVIDENCE: IV.

Structural and biochemical analysis of phosphoethanolamine methyltransferase from the pine wilt nematode Bursaphelenchus xylophilus.

In free-living and parasitic nematodes, the methylation of phosphoethanolamine to phosphocholine provides a key metabolite to sustain phospholipid biosynthesis for growth and development. Because the phosphoethanolamine methyltransferases (PMT) of nematodes are essential for normal growth and development, these enzymes are potential targets of inhibitor design. The pine wilt nematode (Bursaphelenchus xylophilus) causes extensive damage to trees used for lumber and paper in Asia. As a first step toward testing BxPMT1 as a potential nematicide target, we determined the 2.05 Å resolution x-ray crystal structure of the enzyme as a dead-end complex with phosphoethanolamine and S-adenosylhomocysteine. The three-dimensional structure of BxPMT1 served as a template for site-directed mutagenesis to probe the contribution of active site residues to catalysis and phosphoethanolamine binding using steady-state kinetic analysis. Biochemical analysis of the mutants identifies key residues on the ß1d-α6 loop (W123F, M126I, and Y127F) and ß1e-α7 loop (S155A, S160A, H170A, T178V, and Y180F) that form the phosphobase binding site and suggest that Tyr127 facilitates the methylation reaction in BxPMT1.

Assessment and Trends in the Methodological Quality of the Top 50 Most Cited Articles in Shoulder Instability.

BACKGROUND: Citation counts have often been used as a surrogate for the scholarly impact of a particular study, but they do not necessarily correlate with higher-quality investigations. In recent decades, much of the literature regarding shoulder instability is focused on surgical techniques to correct bone loss and prevent recurrence. PURPOSE: To determine (1) the top 50 most cited articles in shoulder instability and (2) if there is a correlation between the number of citations and level of evidence or methodological quality. STUDY DESIGN: Cross-sectional study. METHODS: A literature search was performed on both the Scopus and the Web of Science databases to determine the top 50 most cited articles in shoulder instability between 1985 and 2019. The search terms used included "shoulder instability," "humeral defect," and "glenoid bone loss." Methodological scores were calculated using the Modified Coleman Methodology Score (MCMS), Jadad scale, and Methodological Index for Non-Randomized Studies (MINORS) score. RESULTS: The mean number of citations and mean citation density were 222.7 ± 123.5 (range, 124-881.5) and 16.0 ± 7.9 (range, 6.9-49.0), respectively. The most common type of study represented was the retrospective case series (evidence level, 4; n = 16; 32%) The overall mean MCMS, Jadad score, and MINORS score were 61.1 ± 10.1, 1.4 ± 0.9, and 16.0 ± 3.0, respectively. There were also no correlations found between mean citations or citation density versus each of the methodological quality scores. CONCLUSION: The list of top 50 most cited articles in shoulder instability comprised studies with low-level evidence and low methodological quality. Higher-quality study methodology does not appear to be a significant factor in whether studies are frequently cited in the literature.

Medicaid payer status and other factors associated with hospital length of stay in patients undergoing primary lumbar spine surgery.

OBJECTIVE: The Medicaid patient population and health care costs for spine surgeries among these patients have increased since 2010. Hospital length of stay (LOS) contributes appreciably to hospital costs for patients undergoing primary lumbar spine surgery (PLSS). The aim of this study was to identify independent risk factors for increased LOS in patients undergoing PLSS. PATIENTS AND METHODS: In a single-center retrospective study, we reviewed demographic and clinical data from electronic medical records for 181 consecutive adult patients who underwent PLSS involving 1-3 levels from July 2014 to July 2017. We performed regression analyses to identify independent risk factors for increased LOS and to quantify their effects as percent changes in LOS. RESULTS: Among 181 patients who underwent PLSS, the mean LOS was 3.57 days. Based on the Charlson Comorbidity Index (CCI) and American Society of Anesthesiologist (ASA) classification, patients with Medicaid insurance were healthier than non-Medicaid patients (mean CCI: 0.34 versus 0.65; p = 0.041, ASA: 1.71 versus 1.91; p = 0.046) yet Medicaid patients had a longer LOS compared with non-Medicaid patients (mean LOS: 4.03 versus 3.30 days; p = 0.047). There was no significant difference in discharge disposition between Medicaid and non-Medicaid patients (Home = 82.35 % versus 79.65 %; p = 0.855). Medicaid patients also had significantly less spinal levels involved in their surgery (1.44 versus 1.67; p = 0.027). Multivariable regression modeling identified independent risk factors positively associated with increased LOS as age (+1.0 % per year; p = 0.007), Medicaid insurance status (+28.7 %; p = 0.007), and CCI (10.1 % per increment in CCI; p = 0.030). Fusion surgery also was an independent risk factor for increased LOS when compared with laminectomy (-54.1 %; p < 0.001) or discectomy (-51.3 %; p < 0.001). CONCLUSIONS: Increasing age, Medicaid insurance status, higher CCI, and fusion surgery were independently associated with increased LOS after PLSS. This information is useful for preoperative patient counseling, shared decision-making, and risk stratification and may help to further ongoing discussion regarding contributors to rising health care costs. Findings of increased LOS among Medicaid patients will help direct efforts to identify factors that contribute to this health care expense.

A 15-Minute Incremental Increase in Operative Duration Is Associated With an Additional Risk of Complications Within 30 Days After Arthroscopic Rotator Cuff Repair.

BACKGROUND: Operative time is a risk factor for short-term complications after orthopaedic procedures; however, it has yet to be investigated as an independent risk factor for postoperative complications after arthroscopic rotator cuff repair. PURPOSE: To determine whether operative time is an independent risk factor for complications, readmissions, and extended hospital stays within 30 days after arthroscopic rotator cuff repair. STUDY DESIGN: Descriptive epidemiology study. METHODS: The American College of Surgeons National Surgical Quality Improvement Program was queried for all hospital-based inpatient and outpatient arthroscopic rotator cuff repairs (Current Procedural Terminology code 29827) from 2005 to 2016. Concomitant procedures such as subacromial decompression, biceps tenodesis, superior labrum anterior and posterior (SLAP) repair, labral repair, and distal clavicle excision were also included, whereas patients undergoing arthroplasty were excluded from the study. Operative time was correlated with patient demographics, comorbidities, and concomitant procedures. All adverse events were correlated with operative time, while controlling for the above preoperative variables, using multivariate Poisson regression with a robust error variance. RESULTS: A total of 27,524 procedures met inclusion and exclusion criteria. The mean age of patients was 58.4 ± 10.9 years, the mean operative time was 86.9 ± 37.4 minutes, and the mean body mass index was 30.4 ± 7.0 kg/m2. Concomitant biceps tenodesis, glenohumeral debridement, SLAP repair, labral repair, and distal clavicle excision significantly increased operative time (P < .001) but not the risk of adverse events (P > .05). The overall rate of adverse events was 0.88%. After adjusting for demographic and procedural characteristics, a 15-minute increase in operative duration was associated with an increased risk of anemia requiring transfusion (relative risk [RR], 1.27 [95% CI, 1.14-1.42]; P < .001), venous thromboembolism (RR, 1.17 [95% CI, 1.02-1.35]; P = .029), surgical site infection (RR, 1.13 [95% CI, 1.03-1.24]; P = .011), and extended length of hospital stay (RR, 1.07 [95% CI, 1.00-1.14]; P = .036). CONCLUSION: Although the rate of short-term complications after arthroscopic rotator cuff repair is low, incremental increases in operative time are associated with an increased risk of adverse events such as surgical site infection, pulmonary embolism, transfusion, and extended length of hospital stay. Efforts should be made to maximize surgical efficiency in the operating room through optimal coordination of the staff or increased preoperative planning.