Return to work after subacromial decompression, diagnostic arthroscopy, or exercise therapy for shoulder impingement: a randomised, placebo-surgery controlled FIMPACT clinical trial with five-year follow-up

BACKGROUND: Arthroscopic subacromial decompression is one of the most commonly performed shoulder surgeries in the world. It is performed to treat patients with suspected shoulder impingement syndrome, i.e., subacromial pain syndrome. Only few studies have specifically assessed return-to-work rates after subacromial decompression surgery. All existing evidence comes from open, unblinded study designs and this lack of blinding introduces the potential for bias. We assessed return to work and its predictors in patients with shoulder impingement syndrome in a secondary analysis of a placebo-surgery controlled trial. METHODS: One hundred eighty-four patients in a randomised trial had undergone arthroscopic subacromial decompression (n = 57), diagnostic arthroscopy, a placebo surgical intervention, (n = 59), or exercise therapy (n = 68). We assessed return to work, defined as having returned to work for at least two follow-up visits by the primary 24-month time point, work status at 24 and 60 months, and trajectories of return to work per follow-up time point. Patients and outcome assessors were blinded to the assignment regarding the arthroscopic subacromial decompression vs. diagnostic arthroscopy comparison. We assessed the treatment effect on the full analysis set as the difference between the groups in return-to-work rates and work status at 24 months and at 60 months using Chi-square test and the predictors of return to work with logistic regression analysis. RESULTS: There was no difference in the trajectories of return to work between the study groups. By 24 months, 50 of 57 patients (88%) had returned to work in the arthroscopic subacromial decompression group, while the respective figures were 52 of 59 (88%) in the diagnostic arthroscopy group and 61 of 68 (90%) in the exercise therapy group. No clinically relevant predictors of return to work were found. The proportion of patients at work was 80% (147/184) at 24 months and 73% (124/184) at 60 months, with no difference between the treatment groups (p-values 0.842 and 0.943, respectively). CONCLUSIONS: Arthroscopic subacromial decompression provided no benefit over diagnostic arthroscopy or exercise therapy on return to work in patients with shoulder impingement syndrome. We did not find clinically relevant predictors of return to work either. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00428870.