Loss of Functional Internal Rotation Following Various Combinations of Bilateral Shoulder Arthroplasty

Limited internal rotation (IR) remains a concern for activities of daily living (ADLs) following bilateral shoulder arthroplasty (BSA). The purpose of this study was to evaluate the loss of the ability to perform functional IR tasks following BSA using various combinations of anatomic (TSA) and reverse (RSA) shoulder arthroplasty.

A retrospective review of an institutional shoulder-surgery database was conducted for patients who underwent BSA with any combination of TSA or RSA with at least a 2-year follow-up. IR range of motion (ROM) and individual American Shoulder and Elbow Surgeons (ASES) score and Simple Shoulder Test (SST) questions specific to IR were used to assess a patient's ability to perform IR tasks with at least one of their shoulders.

Seventy-three patients met the inclusion criteria (47 TSA/TSA, 17 RSA/RSA, and 9 TSA/RSA). Average age at surgery was 72.1 years. Average follow-up was 51.4 months. Loss of ability to wash one's back was observed in 30.4% TSA/TSA, 33.3% TSA/RSA, and 52.9% RSA/RSA. Loss of ability to tuck in a shirt was observed in 10.6% TSA/TSA, 11.1% TSA/RSA, and 29.4% RSA/RSA. Loss of ability to manage toileting was observed in no TSA/TSA or TSA/RSA, but in 11.8% RSA/RSA. For each of the tasks, there were no significant differences in the ability to perform the task among the groups (p>0.05). Post-operative IR ROM for TSA/TSA was superior to those for TSA/RSA and RSA/RSA (p<0.01). IR ROM efficacies for both RSA/RSA and TSA/RSA were inferior to that for TSA/TSA (p<0.05).

Bilateral RSA patients can perform most IR tasks, and their ability to complete these tasks does not differ significantly from those in patients with other BSA.