Robot-Assisted Total Hip Arthroplasty is Associated with an Increased Risk of Periprosthetic Fracture.

INTRODUCTION: Total Hip Arthroplasty (THA) aims to restore joint function and relieve pain. New technology, such as robot assistance, offers the potential to reduce human error, improve precision, and improve postoperative outcomes. The aim of this study was to compare outcomes between conventional and robot-assisted THA. METHODS: This is a retrospective cohort study utilizing a national database from 2016 to 2019. Patients undergoing THA, conventional or robot-assisted, were identified via the International Classification of Diseases, Tenth Revision (ICD-10) code. Multivariate regressions were performed to assess outcomes between groups. Negative binomial regressions were performed to assess discharge disposition, readmission, and reoperation. Gamma regressions with log-link were used to assess total charges and lengths of hospital stays. Patient demographics and comorbidities, measured via the Elixhauser comorbidity index, were controlled for in our analyses. A total of 1,216,395 patients undergoing THA, 18,417 (1.51%) with robotic assistance, were identified. RESULTS: Patients undergoing robot-assisted procedures had increased surgical complications (odds ratio (OR) 1.31 [95% CI (confidence interval) 1.14 to 1.53]; P < 0.001), including periprosthetic fracture (OR 1.63 [95% CI 1.35 to 1.98]; P < 0.001). Notably, these patients also had significantly greater total charges (OR 1.20 [95% CI 1.11 to 1.30]; P < 0.001). CONCLUSION: Robotic assistance in THA is associated with an increased risk of surgical complications, including periprosthetic fracture, while incurring greater charges.

A Geometrical Explanation for Change in Pelvic Tilt (or Lack of Change) Following Long Spinal Fusions.

STUDY DESIGN: Retrospective Cohort. OBJECTIVE: Examine the relationship between compensatory pelvic retroversion, positive sagittal imbalance (measured by C2 tilt), and the C2 pelvic angle (C2PA) in patients prior to long spinal fusions; and to determine the association between changes in C2PA and pelvic tilt (PT) following long spinal fusions. BACKGROUND: Adult spinal deformity surgical goals often include a PT target, yet patients frequently demonstrate persistent compensatory pelvic retroversion following surgery. MATERIALS AND METHODS: Adults>18y undergoing long spinal fusions (>4 levels) with standing preoperative and postoperative radiographs were included. To examine drivers of preoperative sagittal balance, regression models were fit to estimate the association between preoperative C2PA and pelvic incidence, with preoperative PT and C2 tilt. To predict postoperative change in PT, multivariable regression was used to estimate change in PT, adjusting for change in C2PA and preoperative C2 tilt. RESULTS: Among 80 patients identified, median age was 61 (IQR, 45 to 72) and 46 (58%) were female. Median number of levels fused was 10 (IQR, 8 to 13) and 55 (69%) were instrumented to the sacrum/pelvis. Preoperative C2PA had a significant nonlinear association with preoperative PT (r2=0.81, P<0.001), and preoperative C2 tilt (r2=0.41, P=0.002). Postoperative change in PT was strongly associated with change in C2PA (ß=0.81; P<0.001) and preoperative C2 tilt (ß=0.55; P<0.001). CONCLUSIONS: Following long spinal fusions, change in PT (or lack thereof) can be reliably predicted based on change in C2PA and preoperative C2 tilt. In patients with normal preoperative C2 tilt, the change in C2PA is nearly equivalent to the change in PT, but in patients with more positive C2 tilt (sagittal imbalance), a greater change in C2PA will be required to achieve equivalent change in PT. LEVEL OF EVIDENCE: III.

A component-based analysis of metabolic syndrome's impact on 30-day outcomes after hip fracture: reduced mortality in obese patients.

Introduction: Hip fractures are a common injury associated with significant morbidity and mortality. In the United States, there has been a rapid increase in the prevalence of metabolic syndrome (MetS), a condition comprised several common comorbidities, including obesity, diabetes mellitus, and hypertension, that may worsen perioperative outcomes. This article assesses the impact of MetS and its components on outcomes after hip fracture surgery. Methods: Patients who underwent nonelective operative treatment for traumatic hip fractures were identified in the 2015-2020 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Baseline characteristics between groups were compared, and significant differences were included as covariates. Multivariate regression was performed to assess the impact of characteristics of interest on postoperative outcomes. Patients with MetS, or a single one of its constitutive components-hypertension, diabetes, and obesity-were compared with metabolically healthy cohorts. Results: In total 95,338 patients were included. Patients with MetS had increased complications (OR 1.509; P < 0.001), but reduced mortality (OR 0.71; P < 0.001). Obesity alone was also associated with increased complications (OR 1.14; P < 0.001) and reduced mortality (OR 0.736; P < 0.001). Both hypertension and diabetes alone increased complications (P < 0.001) but had no impact on mortality. Patients with MetS did, however, have greater odds of adverse discharge (OR 1.516; P < 0.001), extended hospital stays (OR 1.18; P < 0.001), and reoperation (OR 1.297; P = 0.003), but no significant difference in readmission rate. Conclusion: Patients with MetS had increased complications but decreased mortality. Our component-based analysis showed had obesity had a similar effect: increased complications but lower mortality. These results may help surgeons preoperatively counsel patients with hip fracture about their postoperative risks.

Effects of mesenchymal stromal cell-conditioned media on measures of lung structure and function: a systematic review and meta-analysis of preclinical studies.

BACKGROUND: Lung disease is a leading cause of morbidity and mortality. A breach in the lung alveolar-epithelial barrier and impairment in lung function are hallmarks of acute and chronic pulmonary illness. This review is part two of our previous work. In part 1, we demonstrated that CdM is as effective as MSCs in modulating inflammation. Herein, we investigated the effects of mesenchymal stromal cell (MSC)-conditioned media (CdM) on (i) lung architecture/function in animal models mimicking human lung disease, and (ii) performed a head-to-head comparison of CdM to MSCs. METHODS: Adhering to the animal Systematic Review Centre for Laboratory animal Experimentation protocol, we conducted a search of English articles in five medical databases. Two independent investigators collected information regarding lung: alveolarization, vasculogenesis, permeability, histologic injury, compliance, and measures of right ventricular hypertrophy and right pulmonary pressure. Meta-analysis was performed to generate random effect size using standardized mean difference with 95% confidence interval. RESULTS: A total of 29 studies met inclusion. Lung diseases included bronchopulmonary dysplasia, asthma, pulmonary hypertension, acute respiratory distress syndrome, chronic obstructive pulmonary disease, and pulmonary fibrosis. CdM improved all measures of lung structure and function. Moreover, no statistical difference was observed in any of the lung measures between MSCs and CdM. CONCLUSIONS: In this meta-analysis of animal models recapitulating human lung disease, CdM improved lung structure and function and had an effect size comparable to MSCs.

Mesenchymal stem cells and their application to rotator cuff pathology: A meta-analysis of pre-clinical studies.

Background: Rotator cuff injury (RCI) is a leading cause of morbidity in orthopaedics. Advances in regenerative medicine have led to the novel pleiotropic effects of mesenchymal stromal cells (MSCs) as therapeutic agents for RCI. Objective: Conduct a systematic evaluation of available preclinical studies to quantify the effects of MSCs on RCI. Methods: A literature search was performed in PubMed, Scopus, Cochrane, CINAHL, and Google Scholar. At least two independent investigators screened animal studies assessing the therapeutic effects of MSCs on: (i) biomechanical testing, imaging, and/or range-of-motion (primary outcome), and (ii) histologic analyses of wound healing, gene/protein expression of regenerative factors, and safety/long-term outcomes (secondary outcome). Meta-analysis data is reported as standardized mean difference (SMD) with 95% confidence interval (CI). Results: A total of 858 titles and abstracts were screened; 18 studies (n=576) met inclusion criteria. MSC therapy improved ultimate load failure [SMD -0.43 (95% CI -0.65, -0.22), p<0.0001; 15 studies, 28 comparisons], site stiffness [SMD -0.29 (95% CI -0.55, -0.04), p<0.05; 9 studies, 17 comparisons], bone mineral density [SMD -0.77 (95% CI -1.16, -0.38), p<0.0001; 2 studies, 6 comparisons], and stimulated fibrocartilage formation [SMD of -1.37 (95% CI -1.99, -0.74), p<0.0001; 4 studies, 7 comparisons]. Heterogeneity between studies was high and risk of bias was unclear. Conclusion: Administration of MSCs in preclinical models recapitulating RCI improved aspects of shoulder biomechanics, imaging, and collagen formation. Although these findings are promising, future studies should attempt to limit the risk of bias and focus on optimizing MSCs by standardizing methodologies.

Mesenchymal stromal cell conditioned media for lung disease: a systematic review and meta-analysis of preclinical studies.

BACKGROUND: Inflammation plays an important role in the pathogenesis of many lung diseases. Preclinical studies suggest that mesenchymal stromal cell (MSC) conditioned media (CdM) can attenuate inflammation. Our aim was threefold: (1) summarize the existing animal literature evaluating CdM as a therapeutic agent for pediatric/adult lung disease, (2) quantify the effects of CdM on inflammation, and (3) compare inflammatory effects of CdM to MSCs. METHODS: Adhering to the Systematic Review Protocol for Animal Intervention Studies, a systematic search of English articles was performed in five databases. Meta-analysis and meta-regression were performed to generate random effect size using standardized mean difference (SMD). RESULTS: A total of 10 studies met inclusion. Lung diseases included bronchopulmonary dysplasia, asthma, pulmonary hypertension, and acute respiratory distress syndrome. CdM decreased inflammatory cells (1.02 SMD, 95% CI 0.86, 1.18) and cytokines (0.71 SMD, 95% CI 0.59, 0.84). The strongest effect for inflammatory cells was in bronchopulmonary dysplasia (3.74 SMD, 95% CI 3.13, 4.36) while pulmonary hypertension had the greatest reduction in inflammatory cytokine expression (1.44 SMD, 95% CI 1.18, 1.71). Overall, CdM and MSCs had similar anti-inflammatory effects. CONCLUSIONS: In this meta-analysis of animal models recapitulating lung disease, CdM improved inflammation and had an effect size comparable to MSCs. While these findings are encouraging, the risk of bias and heterogeneity limited the strength of our findings.