To investigate the clinical efficacy of ORIF for treating humeral head split fractures.

A retrospective analysis was conducted on seven patients with humeral head split fractures involving >20% of the articular surface, with displacement of >2 mm or angulation of >20°, who were treated between July 2017 and February 2023. All patients underwent ORIF. Fracture exposure was achieved via a superior two-thirds subscapularis tenotomy and an interval approach between the supraspinatus and infraspinatus muscles. The articular fracture fragments were fixed with countersunk screws, followed by definitive fixation using a locking plate. Postoperative follow-up averaged 33.4 months. Functional outcomes were assessed using the Constant and ASES (American Shoulder and Elbow Surgeons) scores. Complications were recorded.

At the final follow-up, the functional scores were favourable (adjusted Constant score: 75.4±8.6; ASES score: 88.4±7.2). However, abduction strength was significantly weaker on the surgical side than on the non-surgical side (surgical side: 51±5.1 vs. non-surgical side: 79±17; P=0.002). However, no significant difference was found in internal rotation strength (P=0.96). One patient experienced malreduction of the articular surface and one patient developed humeral head osteonecrosis.

Open reduction and internal fixation (ORIF) enables anatomical reduction and stable fixation of humeral head split fractures, providing good mid-term functional outcomes for patients aged under 65 years and potentially reducing the risk of osteonecrosis. However, specific attention to restoring abduction strength is warranted.