Comparing patient-reported outcome measures and physical examination for internal rotation in patients undergoing reverse shoulder arthroplasty: does surgery alter patients' perception of function?

Abstract

Background: The purpose of this study was to evaluate how patients treated with reverse shoulder arthroplasty (RSA) achieve internal rotation (IR) using video assessment and to compare this to patient-reported outcome measures (PROMs). Methods: We reviewed 215 preoperative and 657 postoperative videos (3-78 months) for 215 patients who underwent primary RSA, performing IR using the modified vertebral level method. Their functional motion pattern was then grouped into 3 types: type I, could not reach behind their back; type II, able to reach to at least waist level, with assistance; and type III, able to reach to a minimum of waist level in an uninterrupted fashion. Patients completed functional questions (put on a coat, wash back, tuck in a shirt, and manage toileting) and a diagram of perceived IR. Patients' functional motion types were compared to PROM answers. Pre-and postoperative scores were also compared to assess the effect of surgery on patients' perception of IR function. Results: Patients undergoing RSA will achieve IR in 3 distinct motion patterns. Analysis of self-reported IR indicated statistically significant difference between the 3 functional types of IR (P < .001). Patient-perceived IR was not significantly different between the 3 studied IR functional types (P ¼ .076) in the analysis of preoperative measures but was significantly different in the postoperative setting (P < .001). Conclusion: Patients attempt IR in 3 distinct functional motion patterns. The improvement of IR after RSA is measured better by patient questionnaires than by physical examination.This study was determined to be exempt from review by the Western Institutional Review Board (WIRB).