Abstract
INTRODUCTION: Plate osteosynthesis is preferred for the treatment of proximal humerus fractures (PHFs). However, applying the locking plate flush against the bone may lead to varus malreduction and medial displacement of the humeral head. We hypothesized that slight valgus reduction and valgus bent locking plate fixation against potential varus deformation would yield better results than the traditional plate fixation. METHODS: We retrospectively reviewed patients with PHFs treated with locking plate fixation between March 2014 and July 2019. We evaluated changes in the neck-shaft angle (NSA) and humeral head height, as well as the development of complications postoperatively. Clinical outcomes were measured at 1-year post-surgery and at the last follow-up using the American Shoulder and Elbow Surgeons, the Disabilities of the Arm, Shoulder and Hand, and the Constant-Murley scores. RESULTS: A total of 58 patients with PHFs were enrolled in this study. They were divided into the valgus-aligned group (n = 28) and the anatomical group (n = 30). According to radiographic evaluation, immediate postoperative NSA was significantly greater in the valgus-aligned group. Moreover, the NSA measured at the last follow-up was significantly greater the valgus-aligned group. In contrast, the NSA became considerably more varus-aligned in the anatomical group. CONCLUSION: The appropriate valgus reduction and valgus bending plate fixation could lead to better short-term results and improve the ability of proximal humerus locking plates to prevent varus collapse and fixation failure. LEVEL OF EVIDENCE: Level III, retrospective cohort design.