Establishing maximum medical improvement following reverse total shoulder arthroplasty for rotator cuff deficiency

Abstract

Background: Since US Food and Drug Administration approval of the reverse prosthesis in 2003, the incidence of shoulder arthroplasty in the United States has risen dramatically. With increasing demand, efforts have shifted from traditional volume-based health care models to more patient-centered care. The purpose of this systematic literature review is to establish the time point of maximum medical improvement (MMI) following reverse total shoulder arthroplasty (rTSA).

Materials and methods: We conducted a systematic review of studies reporting validated patient-reported outcome measures (PROMs) across multiple postoperative time points following rTSA. Established minimal clinically important difference values for PROMs specific to shoulder arthroplasty were used to determine significant clinical improvement. The time point beyond which significant improvement did not occur was established as MMI.

Results: MMI occurred at 1 postoperative year following rTSA. When preoperative measures were compared with 1-year postoperative outcomes, all but 1 PROM demonstrated significant clinical improvement (P < .001). There were no significant improvements between any 2 subsequent time points beyond 1 year (P > .050). Range of motion significantly improved between preoperative and 1-year levels (P < .001). No PROMs or range-of-motion parameters significantly improved beyond 1 year (P > .999).

Conclusions: Patients achieved MMI at 1 postoperative year following rTSA. Patients showed rapid improvements in subjective symptoms within the first 3 months and continued to gradually improve until 1 year. Surgeons should counsel patients with these evidence-based expectations for clinical recovery, particularly the time frame of expected improvements in pain, function, and range of motion, as well as risks of and plans of action for postoperative complications.

Keywords: Reverse total shoulder arthroplasty; maximum improvement; maximum medical improvement; rotator cuff; rotator cuff tear arthropathy; shoulder arthroplasty.