Tuberosity Healing in Reverse Shoulder Arthroplasty for Proximal Humeral Fractures with a Diaphyseal Press-Fit Humeral Stem

Abstract

IntroductionReverse shoulder arthroplasty (RSA) is a viable option for proximal humerus fractures (PHFs) in the elderly and cemented humeral fixation is the standard of care. This study evaluates the influence of a diaphyseal press fit stem with a 142o humeral inclination on tuberosity healing (TH) and functional outcome in RSA for PHF. MethodsTwenty-three patients received a RSA for PHF by a single surgeon at one center over a 2 year period. The humeral stem design was intended for diaphyseal press fit with a 142o humeral inclination. The tuberosities were repaired for each patient with bone graft and a standard suture technique. Patient clinical and radiographic outcomes were collected with a minimum 12 month follow-up. ResultsNineteen of 23 patients (83%) with a mean age of 75 + years were available for follow-up at an average of 14 months. Radiographic analysis showed 68% of patients had evidence of TH. Grade 1 scapular notching was found in 32% of patients. There was no implant loosening or subsidence noted. Average range of motion was 163o+ 15o degrees of forward flexion, 113o+ 24o of abduction, internal rotation to the waist and an average external rotation of 7 + 1.5 as measured by the Constant-Murley score. Average ASES score was 81.8 and average Constant Murley score was 67.9. While not significant, those with TH trended towards better clinical outcomes. There was a 0% revision rate. ConclusionA press fit stem designed for diaphyseal fixation provides consistent reliable results in RSA for PHF. A high percentage of TH was appreciated with a 142o humeral inclination, neutral glenosphere construct and a standardized bone grafting, suture technique. TH is associated with improved patient outcomes.