Humeral shaft fractures: union outcomes in a large cohort.

Background: Humeral shaft fractures can be managed conservatively or operatively. Fracture characteristics were analyzed to identify patients who would benefit from early operative fixation.

Methods: We performed a retrospective cohort study of 126 consecutive humeral shaft fractures (2008-2015). Fractures were classified according to fracture type, location, separation, and comminution.

Results: Of 126 patients, 96 were managed conservatively. In 54%, union occurred before 26 weeks, and 13% had delayed union after 26 weeks, whereas 33% did not achieve union. Of 30 patients managed surgically, 63% had union before 26 weeks, 33% had delayed union, and 4% did not achieve union. A statistically significant difference favored operative management. This difference was maintained in specific fracture patterns (simple and spiral fractures) and locations (proximal- or distal-third humeral fractures). Early surgery had a significantly higher union rate than delayed surgery. No difference was present between plate and nail fixation regarding union or neurologic injury. Separation of fragments, open injury, and comminution were not associated with nonunion. A psychiatric history (including psychotic disorders, bipolar disorder, multiple involuntary psychiatric admissions, or dementia) was significantly associated with nonunion after conservative management (P = .016). Two patients with dementia died after their conservatively managed fractures progressed to open injuries.

Conclusion: This study found high rates of delayed union and nonunion with conservative management. Patients with a significant psychiatric history may benefit from consideration of operative intervention.