OBJECTIVES: To evaluate clinical and radiographic outcomes and complications of three- and four-part proximal humerus fractures (PHF) in elderly patients treated with angular locking plate (LP) combined with calcium sulfate (CaSO MATERIALS AND METHODS: A prospective case series evaluating patients aged ≥ 60 years with three- or four-part PHF treated with LP and 10 ml of CaSO RESULTS: Thirty patients were evaluated. At 12 months, the mean scores were: 67.7 (CM), 30.5 (UCLA), 86.5 (ASES), 0.7 (VAS), and 18.9 (DASH). The mean active ROM was 121° (flexion), 109° (abduction), 53° (external rotation), and thumb-T12, with abduction strength of 5.7 kg. The mean head-shaft angle (HSA) on the first postoperative day was 133°, with minimal change to 129° at 12 months, and the mean humeral height (HH) remained unchanged (11 mm). There were five complications in four patients (13.3%): three cases of severe varus collapse (difference between the neck-shaft angle (NSA) on the first postoperative day and the 12th month postoperative >
20°), and two cases of cutout. Two reoperations (6.0%) were performed to remove screws that had penetrated the joint. CONCLUSION: Clinical and radiographic outcomes of three- or four-part PHF in elderly patients treated with LP and CaSO