Lakshmanan Sivasundaram

BACKGROUND: Computer navigation and robotic assistance technologies are used to improve the accuracy of component positioning in total knee arthroplasty (TKA), with the goal of improving function and optimizing implant longevity. The purpose of this study was to analyze trends in the use of technology-assisted TKA, identify factors associated with the use of these technologies, and describe potential drivers of cost. METHODS: The Nationwide Inpatient Sample database was used to identify patients who underwent TKA using conventional instrumentation, computer navigation, and robot-assisted techniques between 2005 and 2014. Variables analyzed include patient demographics, hospital and payer types, and hospital charges. Descriptive statistics were used to describe trends. Univariate and multivariate analyses were performed to identify differences between conventional and technology-assisted groups. RESULTS: Our analysis identified 6,060,901 patients who underwent TKA from 2005 to 2014, of which 273,922 (4.5%) used computer navigation and 24,084 (0.4%) used robotic assistance. The proportion of technology-assisted TKAs steadily increased over the study period, from 1.2% in 2005 to 7.0% in 2014. Computer navigation increased in use from 1.2% in 2005 to 6.3% in 2014. Computer navigation was more likely to be used in the Western United States, whereas robot-assisted TKAs were more likely to be performed in the Northeast. Increased hospital charges were associated with the use of technology assistance ($53,740.1 vs $47,639.2). CONCLUSIONS: The use of computer navigation and robot-assisted TKA steadily increased over the study period, accounting for 7.0% of TKAs performed in the United States in 2014. Marked regional differences in the use of these technologies were identified. The use of these technologies was associated with increased hospital charges.

PURPOSE: The purpose of this study was to evaluate a large population of shoulder arthroscopy cases in order to provide insight into the risk factors associated with readmission following this common orthopaedic procedure. METHODS: The American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database was queried using current procedural terminology (CPT) billing codes to identify all patients older than 18 years of age who underwent shoulder arthroscopy between 2011 and 2013. Univariate and multivariate analyses were conducted to identify factors associated with 30-day readmission. RESULTS: We identified 15,015 patients who had undergone shoulder arthroscopy, with a 30-day readmission rate of 0.98%. The most common reason for readmission was pulmonary embolism (0.09%). On multivariate analysis, operative time > 1.5 hours (odds ratio [OR], 1.80; 95% confidence interval [CI], 1.29 to 2.50), age 40 to 65 years (OR, 3.80; 95% CI, 1.37 to 10.59), age > 65 years (OR, 3.91; 95% CI, 1.35 to 11.35), American Society of Anesthesiologists (ASA) class 3 (OR, 4.53; 95% CI, 1.90 to 10.78), ASA class 4 (OR, 7.73; 95% CI, 2.91 to 27.25), chronic obstructive pulmonary disease (COPD; OR, 2.65; 95% CI, 1.54 to 4.55), and chronic steroid use (OR, 2.96; 95% CI, 1.46 to 6.01) were identified as independent risk factors for readmission. CONCLUSIONS: Operative time > 1.5 hours, age > 40 years, ASA classes 3 or 4, COPD, and chronic steroid use are independent risk factors for readmission following elective arthroscopic shoulder surgery, although the readmission rate following these procedures is low. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Background: Although initial studies have demonstrated that concentrated bone marrow aspirate (cBMA) injections promote rotator cuff repair (RCR) healing, there are no randomized prospective studies investigating clinical efficacy. Hypothesis/Purpose: To compare outcomes after arthroscopic RCR (aRCR) with and without cBMA augmentation. It was hypothesized that cBMA augmentation would result in statistically significant improvements in clinical outcomes and rotator cuff structural integrity. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: Patients indicated for aRCR of isolated 1- to 3-cm supraspinatus tendon tears were randomized to receive adjunctive cBMA injection or sham incision. Bone marrow was aspirated from the iliac crest, concentrated using a commercially available system, and injected at the aRCR site after repair. Patients were assessed preoperatively and serially until 2 years postoperatively via the following functional indices: American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), Simple Shoulder Test, 12-Item Short Form Health Survey, and Veterans RAND 12-Item Health Survey. Magnetic resonance imaging (MRI) was performed at 1 year to assess rotator cuff structural integrity according to Sugaya classification. Treatment failure was defined as decreased 1- or 2-year ASES or SANE scores as compared with preoperative baseline, the need for revision RCR, or conversion to total shoulder arthroplasty. Results: An overall 91 patients were enrolled (control, n = 45; cBMA, n = 46): 82 (90%) completed 2-year clinical follow-up and 75 (82%) completed 1-year MRI. Functional indices significantly improved in both groups by 6 months and were sustained at 1 and 2 years (all P < .05). The control group showed significantly greater evidence of rotator cuff retear according to Sugaya classification on 1-year MRI (57% vs 18%; P < .001). Treatment failed for 7 patients in each group (control, 16%; cBMA, 15%). Conclusion: cBMA-augmented aRCR of isolated supraspinatus tendon tears may result in a structurally superior repair but largely fails to significantly improve treatment failure rates and patient-reported clinical outcomes when compared with aRCR alone. Additional study is warranted to investigate the long-term benefits of improved repair quality on clinical outcomes and repair failure rates. Registration: NCT02484950 (ClinicalTrials.gov identifier).