Is outpatient shoulder arthroplasty safe in patients aged ≥65 years? A comparison of readmissions and complications in inpatient and outpatient settings.

BACKGROUND: Recent studies indicate that outpatient total shoulder arthroplasty (TSA) is cost-effective and may have a low complication rate similar to inpatient TSA. However, existing studies have included younger patient cohorts who typically possess fewer medical comorbidities. Patients aged ≥65 years are commonly enrolled in Medicare, which has traditionally designated TSA as an inpatient-only procedure. The purpose of this study was to compare surgical complication rates and 90-day readmission rates between inpatient and outpatient TSA performed in adults aged ≥65 years. METHODS: Medical records for all patients aged ≥65 years who underwent primary anatomic or reverse TSA by a single surgeon from July 2015 to May 2020 were reviewed. Patients were preselected for outpatient or inpatient surgery based on lack of significant cardiopulmonary comorbidities and patient preference. Demographics, body mass index (BMI), and American Society of Anesthesiologists (ASA) scores were collected in addition to emergency department (ED) visits and readmissions within 90 days of the index surgery. Relationships among frequency and types of complications and surgical setting (inpatients vs. outpatient) were assessed. Complication rates and demographic variables between inpatient and outpatient procedures were compared. Logistic regressions were performed to account for interacting predictor variables on the odds of having complications. RESULTS: A total of 145 shoulders (138 patients; 95 male, 43 female) were included in the analysis, of which 98 received inpatient TSA and 47 received outpatient TSA. Average age was 75.5 ± 7.2 for inpatient TSA and 70.5 ± 4.5 for outpatient TSA (P < .001). Patient age (P < .001), ASA score ≥3 (P < .001), and reverse TSA (P = .002) were significantly positively correlated with receiving inpatient surgery. There were 16 complications (16.3%) in the inpatient group and 9 complications (19.1%) in the outpatient group (P = .648). There were no significant differences in the frequency of postoperative complications, return to the ED, or reoperations between inpatient and outpatient procedures (P > .05). Each 1-year increase in age increased the predicted odds of having a surgical complication by 14% (odds ratio = 1.14; P = .021), irrespective of surgical setting. Those who underwent inpatient TSA had a significantly higher frequency of 90-day readmission (inpatient=16, outpatient=1; P = .034). CONCLUSIONS: Postoperative complications and ED returns were not significantly different between inpatient and outpatient TSA. Each 1-year increase in age increased the odds of postoperative surgical complications by 14%, regardless of surgical setting. Outpatient TSA was found to be safe for appropriately selected patients aged ≥65 years, and re-evaluation of TSA as an inpatient-only procedure should be considered.

A Geographic Population-level Analysis of Access to Total Shoulder Arthroplasty in the State of Texas.

INTRODUCTION: Managing costs and improving access to care are two important goals of healthcare policy. The purposes of this study were to (1) evaluate the changes in distribution of total shoulder arthroplasty (TSA) cases in the state of Texas from 2010 to 2015 and (2) to evaluate patient access to TSA surgery centers as measured by driving miles. METHODS: Inpatient (IP) and outpatient (OP) records were obtained from 2010 to 2015 from the Texas Department of State Health Services. All primary elective anatomic or reverse TSAs for patients with Texas-based home residence zip codes were included. Driving miles between patient zip codes and their chosen TSA surgery centers were estimated, and the results were compared between IP (high-volume [HV-IP] or low-volume [LV-IP]) and OP centers. Paired student t-tests, multivariate regressions, and mixed-model analysis of variance (ANOVA) were performed for volume comparisons, interactions between TSA centers types, and yearly trend data, respectively. RESULTS: Between 2010 and 2015, a total of 21,092 TSA procedures were performed across 321 surgery centers in the state of Texas (19,629 IP [93.1%] and 1,463 OP [6.9%]). During this time, the cumulative volume of IP TSA per 100,000 Texas residents increased by 109.1%, whereas the cumulative volume of OP TSA increased by 143.7%. Approximately 85.5% of included patients resided within 50 miles of any TSA surgery center; however, only 47.0% of the total Texas population resided within 50 miles of any TSA surgery center. This relationship remained true at every time point irrespective of their volume designations (OP, IP, HV-IP, and LV-IP). CONCLUSION: Despite the overall increase in TSA volume over time, the majority all TSA utilization in the state of Texas occurred in patients who resided within 50 miles of a TSA center. Increasing volume seems to reflect concentration of care into HV-IP and OP centers. Strategies to improve access to TSA care for underserved areas should be considered. LEVEL OF EVIDENCE: Level II.

A comparison of bone regeneration with human mesenchymal stem cells and muscle-derived stem cells and the critical role of BMP.

Adult multipotent stem cells have been isolated from a variety of human tissues including human skeletal muscle, which represent an easily accessible source of stem cells. It has been shown that human skeletal muscle-derived stem cells (hMDSCs) are muscle-derived mesenchymal stem cells capable of multipotent differentiation. Although hMDSCs can undergo osteogenic differentiation and form bone when genetically modified to express BMP2; it is still unclear whether hMDSCs are as efficient as human bone marrow mesenchymal stem cells (hBMMSCs) for bone regeneration. The current study aimed to address this question by performing a parallel comparison between hMDSCs and hBMMSCs to evaluate their osteogenic and bone regeneration capacities. Our results demonstrated that hMDSCs and hBMMSCs had similar osteogenic-related gene expression profiles and had similar osteogenic differentiation capacities in vitro when transduced to express BMP2. Both the untransduced hMDSCs and hBMMSCs formed very negligible amounts of bone in the critical sized bone defect model when using a fibrin sealant scaffold; however, when genetically modified with lenti-BMP2, both populations successfully regenerated bone in the defect area. No significant differences were found in the newly formed bone volumes and bone defect coverage between the hMDSC and hBMMSC groups. Although both cell types formed mature bone tissue by 6 weeks post-implantation, the newly formed bone in the hMDSCs group underwent quicker remodelling than the hBMMSCs group. In conclusion, our results demonstrated that hMDSCs are as efficient as hBMMSCs in terms of their bone regeneration capacity; however, both cell types required genetic modification with BMP in order to regenerate bone in vivo.