Humeral Shaft Fracture Healing Rates in Older Patients.

Nonoperative treatment has become the standard of care for the majority of humeral shaft fractures. Published studies have mainly come from trauma centers with a young cohort of patients. The purpose of this study was to determine the nonunion rate of humeral shaft fractures in patients older than 55 years. A retrospective study was performed on a group of orthopedic trauma group treated at a level I trauma center during a 10-year period (2007-2017). Patients 55 years or older and treated for a humeral shaft fracture nonoperatively, with or without manipulation, were identified. Nonunion was defined by no bridging callus radiographically or by gross motion at the fracture at least 12 weeks from injury. There were 31 patients identified with humeral shaft fractures who met the inclusion criteria. The cohort included 21 (67.7%) females and 10 (32.3%) males with a mean age of 72.5 years (range, 55-92 years). Twenty-one fractures went on to union, and there were 10 nonunions, with no significant differences in the demographics or comorbidities. There was no correlation between AO/OTA fracture classification or fracture location and union status. There was a tendency toward higher risk of nonunion in proximal third humeral shaft fractures (45%) compared with middle (26%) and distal third (20%) humeral shaft fractures, although this was not statistically significant. The overall nonunion rate for humeral shaft fractures was 32% for patients older than 55 years. The authors found a significant correlation between age and union rate: as age increased, union rate decreased (R=-0.9, P=.045). The incidence of humeral shaft nonunion in patients older than 55 years was significantly higher than that of younger adults. To the authors' knowledge, this study is the first to report a significant correlation between nonunion and increased age. [Orthopedics. 2020;43(3);168-172.].