A radiographic analysis of the effects of prosthesis design on scapular notching following reverse total shoulder arthroplasty.

Abstract

Scapular notching is a well-recognized complication of reverse total shoulder arthroplasty (RTSA). This paper analyzes the effects of prosthesis design on scapular notching in RTSA. From a database of all RTSA performed by the senior author, shoulders with minimum 12-month follow-up were included (65 shoulders). Notching in shoulders with a prosthesis neck-shaft angle of 155° and no center-of-rotation (COR) offset (group 1) was compared to notching in shoulders with a neck-shaft angle of 143° and 2.5-mm COR offset (group 2). P values less than .05 were considered significant. The notching grade was significantly higher in group 1 than in group 2, even after statistically adjusting for differences in length of follow-up (P = .0081). The incidence of notching in group 1 at 60.7% was significantly higher than the 16.2% incidence in group 2 (P = .0107). Using prostheses with a smaller neck-shaft angle and increased COR offset can significantly reduce scapular notching in RTSA at 1 year, possibly improving prosthesis survival.