Is reverse total shoulder arthroplasty a feasible treatment option for failed shoulder arthroplasty? A retrospective study of 44 cases with special regards to stemless and stemmed primary implants. BACKGROUND Due to humeral or glenoid bone-loss and rotator cuff insufficiency reverse total shoulder arthroplasty often means the only remaining treatment option in revision shoulder arthroplasty. This study investigates the clinical outcome of patients treated with a reverse total shoulder in revision cases with special regard to stemless and stemmed primary implants. METHODS From 2010 to 2012 60 failed shoulder arthroplasties were converted to reverse total shoulder arthroplasty. Forty-four patients were available for follow-up after a mean of 24 months. Patients were assessed with X-rays, Constant- and ASES Score and a questionnaire about their subjective satisfaction. RESULTS The total number of observed complications was seven (16%). Ninety-eight percent of the patients were satisfied with their clinical result. Patients achieved a mean normalized constant score of 70.2% and a mean ASES Score of 65.3. Patients with stemless primary implants achieved a higher normalized constant score than patients with stemmed primary implants (82 vs. 61.8%; p = 0009). CONCLUSIONS Reverse total shoulder arthroplasty provides satisfactory clinical results and a high patient satisfaction in revision shoulder arthroplasty. The complication rate needs to be considered and discussed with the patient prior to surgery. Presence or absence of a stem of revised shoulder arthroplasties interferes with the outcome. LEVEL OF EVIDENCE IV: (Retrospective study).