Summary

Although performed less frequently, total shoulder arthroplasty is associated with significantly shorter hospital stays, quicker discharges, lower likelihoods of readmission, and fewer complications than total hip and knee arthroplasties.

Abstract

Introduction

Total shoulder arthroplasty (TSA) has been demonstrated as an effective treatment for multiple shoulder pathologies. While numerous studies have compared the associated costs, outcomes, and complications between arthroplasties of the hip (THA) versus knee (TKA), the safety and efficacy of TSA remain poorly characterized. This study leverages a large, risk-adjusted national database to compare operative factors, complication rates, and utilization trends associated with TSA compared to those of THA and TKA.

Methods

The American College of Surgeon’s National Surgical Quality Improvement Program (NSQIP) database was utilized to investigate perioperative outcomes for patients undergoing TSA, THA, or TKA from 2012-2020. Patients included in this study were >18 years old and received a unilateral primary total joint arthroplasty, as determined using CPT codes 23472 (TSA), 27130 (THA), and 27447 (TKA). Patient demographics, comorbidities, operative times, length of stay, readmissions, and serious/minor adverse events were compared between cohorts using Chi-square tests or one-way ANOVA, as appropriate. Utilization trends were assessed using Cochran-Armitage trend tests. Multivariable analyses and binomial logistic regression models adjusted for baseline patient characteristics were employed to compare operative factors, lengths of stay, and 30-day complications. THAs and TKAs were combined into a single comparison group for all adjusted analyses.

Results

Results: Of 748,153 included patients, 32,222 (4.31%), 279,528 (37.36%), and 436,403 (58.33%) underwent TSA, THA, and TKA, respectively. TSA operative times ([mean ± SD]: 109.21 ± 44.62 minutes) were longer than those for THA (91.28 ± 38.48 minutes) and TKA (90.02 ± 34.85 minutes). Conversely, TSA patients experienced shorter hospital stays (1.67 ± 3.36 days; p<0.001) relative to those receiving hip (2.38 ± 3.90 days) or knee (2.38 ± 3.51 days) arthroplasty. Logistic regression models controlling for demographics and comorbidities revealed patients undergoing TSA were less likely to be readmitted [adjusted relative risk (ARR) 0.78, 95% confidence interval (CI) 0.73-0.83] or sustain serious [ARR 0.79, 95% CI 0.73-0.85] or minor [ARR 0.59, 95% CI 0.52-0.66] adverse events than those receiving THA or TKA (p<0.001 for all). Finally, when comparing arthroplasty utilization rates from 2012-2020, the proportion of TSA increased significantly (3.16% to 5.08%) relative to THA (38.4% to 39.8%) and TKA (58.5% to 55.1%; p<0.001).

Discussion

This study demonstrates TSA is associated with lower likelihoods of 30-day readmissions or adverse events than THA and TKA, after controlling for patient demographics and comorbidities. Coupled with literature evincing clinical and functional benefits of TSA, these findings corroborate TSA as a safe and effective treatment for pathologies of the shoulder, and utilization trends from 2012-2020 suggest its relative prevalence may continue to grow.


ACKNOWLEDGEMENTS: Conine Family Foundation for Joint Preservation; Mark Cote DPT, MS at MGH for assistance with statistical analysis.