Anatomic shoulder arthroplasty in workers’ compensation patients: predictors of success and return to work

Abstract

BackgroundIn patients with shoulder arthritis, workers’ compensation (WC) status presents unique challenges to the clinician because of the socioeconomic and psychosocial aspects attendant to patients covered on this type of insurance. Patients, surgeons, and these insurance programs would be informed by a better understanding of the factors that may impact the results of a shoulder arthroplasty as treatment for glenohumeral arthritis in this population. The objectives of this study were to determine: (1) the extent to which patient-reported outcomes are impacted by WC status in comparison to patients covered by other types of insurance, (2) which factors are predictive of a successful outcome of shoulder arthroplasty as defined by improvement exceeding the minimal clinically important difference (MCID), (3) the ability of WC patients to return to their presurgical occupation after arthroplasty. MethodsThis was a retrospective study of a longitudinally maintained institutional database of 677 patients who underwent primary anatomic shoulder arthroplasty with a minimum 2-year follow-up, 39 of whom had WC insurance. These patients were compared to a matched cohort of 78 patients without WC insurance. Primary outcome measures included SST scores, SANE scores, and need for revision surgery. Univariate and multivariate analyses were performed to determine preoperative characteristics associated with success as defined by improvement greater than the MCID of the SST. ResultsSuccess, defined as improvement beyond MCID, occurred in a significantly lower proportion of WC patients compared to non-WC patients (64% vs. 94%, P< .001). Older age (P= .010) and a higher preoperative SF-36 role physical domain score (a measure of the patient's perceived limitations in routine activities;P= .007) were associated with improvement beyond the MCID on univariate analysis. Higher preoperative SF-36 role physical domain scores had the greatest correlation with a successful outcome (OR 1.19, 95% 0.99-1.43, P= .07). A significantly lower percentage of patients with physically-demanding jobs returned to previous occupation compared to patients with non-physically-demanding jobs (13% vs. 73%, P= .001). ConclusionsThe challenges in treating patients covered by WC are underscored by the high percentage of these patients that do not improve beyond the MCID and the high percentage of patients with physically-demanding jobs that are unable to return to their presurgical occupation. Those patients who report less disability with routine daily activities (ie, higher SF-36 role physical domain scores) may fare better with anatomic shoulder arthroplasty. Patients with physically-demanding jobs should be counseled that return to their previous occupation is unlikely. Level of EvidenceLevel III; Retrospective Cohort Comparative Study