*Article* **Reverse Shoulder Arthroplasty for Proximal Humerus Head-Split Fractures—A Retrospective Cohort Study**

**Jan-Philipp Imiolczyk 1,\*, Ulrich Brunner 2, Tankred Imiolczyk 3, Florian Freislederer 4, David Endell 4 and Markus Scheibel 1,4,\***


**Abstract:** Head-split fractures are proximal humerus fractures (PHF) that result from fracture lines traversing the articular surface. While head-split fractures are rare, surgical treatment of these complex injuries can be extremely challenging and is associated with high rates of complications. Treatment using primary reverse shoulder arthroplasty (RSA) has been associated with moderate complication rates and reproducible clinical results. The aim of this study was to evaluate clinical and radiographic outcomes, and complication rates of RSA for head-split PHF. Twenty-six patients were evaluated based on Constant Score (CS) and range of motion of both shoulders and Subjective Shoulder Value (SSV). Radiographic analysis evaluated tuberosity healing, prosthetic loosening and scapular notching. Patients achieved good clinical results with a CS of 73.7 points and SSV of 82% after a mean follow-up of 50 months. The relative CS comparing operated versus the unaffected shoulder was 92%. Greater tuberosity healing was achieved in 61%. Patients who suffered a high-energy trauma reached a significantly greater functional outcome. Patients who suffered multifragmentation to the humeral head performed the worst. There were no cases of loosening; scapular notching was visible in two cases. The complication rate was 8%. RSA is an adequate treatment option with for head-split PHF in elderly patients.

**Keywords:** head split; splitting; tuberosity; healing; union; trauma; humerus; trauma; low; high; energy; double shadow; pelican sign
