Speed of return to normalcy after total shoulder arthroplasty

Understanding outcome expectations is a key component of pre-operative counseling before shoulder arthroplasty. However, the capacity of surgery to restore the shoulder back to normal and how long this may take remains unclear. The purpose of this study is to evaluate shoulder arthroplasty patients who have rated their shoulder as normal, characterize the overall time taken to achieve this level, the time intervals where improvement occurs, and define the plateau in improvement.

A retrospective query of our institution's shoulder and elbow surgery repository identified patients treated with primary anatomic total shoulder arthroplasty (aTSA) or reverse total shoulder arthroplasty (rTSA) between November 2006 and April 2024. Patients were included if they had a post-operative Single Assessment Numeric Evaluation (SANE) score available to review. SANE scores and additional patient-reported outcome measure data were evaluated at all routine post-operative follow-up intervals: 3 months, 6 months, and yearly from 1 year to 10 years. Those patients who reported a SANE score of ≥95 were designated as having returned to normal level of function. The percentage of patients who returned to normal was compared between those treated with aTSA and rTSA. A similar subanalysis comparing aTSA and rTSA patients treated for glenohumeral osteoarthritis (OA) with an intact rotator cuff was also conducted.

A total of 1,399 aTSA and 1,505 rTSA patients met inclusion criteria, with 714 aTSA (51.0%) and 562 rTSA (37.3%) achieving a post-operative SANE score ≥95. aTSA patients returned to normal at a higher rate (P < .001) but did not return to normal faster than rTSA patients (1 year vs. 1 year; P = .607). However, in the OA subanalysis, rTSA patients returned to normal faster than aTSA patients (0.5 year vs. 1 year; P = .020), despite aTSA patients (52.3%) having a higher rate of returning to normal than rTSA patients (42.8%; P < .001). Of those who returned to normal, at least 70% of patients did so within 1 year. Similar trends were observed in the OA cohort. There was a consistent plateau in improvement at three years across all cohorts.

Patients treated with aTSA have a greater chance of rating their shoulder as normal when compared to rTSA, and typically both achieve this level by 1 year. This is true when comparing all indications as well as OA with an intact rotator cuff. However, rTSA patients treated for OA with an intact rotator cuff have a faster return to normal than aTSA patients.