Osteosynthesis of Three- and Four-Part Proximal Humerus Fractures in Elderly Patients Using Locking Plates and Synthetic Bone Grafts: A Clinical and Radiographic Evaluation

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 (CaSO4) paste graft. 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 CaSO4 paste graft. Primary outcome was clinical evaluation using the Constant-Murley (CM) score at 12 months. Secondary outcomes included scores from the University of California, Los Angeles (UCLA), American Shoulder and Elbow Surgeons (ASES), Visual Analog Scale (VAS), Disabilities of the Arm, Shoulder and Elbow (DASH), bilateral active range of motion (ROM), abduction strength, Constant Relative Index (CRI), radiographic findings, and complications. 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 CaSO4 paste graft are satisfactory, with relatively low complications and reoperation rates.