Assessment of Scapular Morphology as a Predictor of Notching in Reverse Shoulder Replacements

BackgroundThere has been increased focus on understanding the risk factors associated with scapular notching in reverse shoulder arthroplasty (RSA). The purpose of this study is to evaluate the effect of scapular morphology and surgical technique on the occurrence of scapular notching using the notching index as a comprehensive predictive tool.MethodsNinety-one patients treated with a primary RSA were followed for a minimum of 24 months. Using a previously published notching index formula ((PSNA × 0.13) + (PGRD)), a notching index value for all patients was calculated. Radiographic assessment of patients were grouped by Nerot grade of scapular notching, group mean differences for prosthetic scapular neck angle (PSNA), peg glenoid rim distance (PGRD), preoperative scapular neck angle (SNA), notching index and clinical outcomes were compared.ResultsSeventy-five (82%) of the ninety one shoulders in the study developed scapular notching. There was no significant difference in average notching index for group ...