Conversion to reverse shoulder arthroplasty: Humeral stem retention versus revision

As the volume of shoulder arthroplasty procedures performed in the United States continues to increase, the predicted number of revision shoulder arthroplasties grows even higher. Conversion of failed shoulder arthroplasty to reverse total shoulder arthroplasty has become common. Many commercially available shoulder arthroplasty systems now offer a platform humeral stem that is used for both anatomic shoulder arthroplasty and reverse total shoulder arthroplasty. This study investigated whether retaining the humeral stem offers advantages over revising the humeral stem in conversion of failed shoulder arthroplasty to reverse total shoulder arthroplasty. The study included 26 patients (mean age, 68.46 years) with failed shoulder arthroplasty who underwent conversion to reverse total shoulder arthroplasty with a minimum 2-year follow-up (mean, 34.38 months). Patients who had retention of the humeral stem were compared with those who had stem revision. Humeral stem retention was associated with a significantly shorter operative time (178.92 vs 237 minutes, P=.02). Decreases in blood loss, complications, and length of hospitalization were observed, but the differences were not statistically significant. Minimal differences were observed for patient-reported outcomes. Of patients undergoing humeral stem removal, 21.4% had an intraoperative humeral shaft or tuberosity fracture compared with none in the stem retention group. Humeral stem retention was associated with decreased operative time compared with humeral stem revision in the conversion of failed shoulder arthroplasty to reverse total shoulder arthroplasty. The use of a platform shoulder arthroplasty system may benefit patients with failed shoulder arthroplasty undergoing conversion to reverse total shoulder arthroplasty by avoiding humeral stem revision.