Humeral shaft fractures are relatively common injuries, with an incidence of 13 per 100,000 per year. There is a bimodal incidence with a peak in the young and elderly, with most cases in the elderly being fragility fractures. Fracture locations in the proximal and middle thirds of the humeral shaft are considered to be fragility fractures,[1] and in the elderly, these fractures are associated with poor post-injury outcomes such as increased mortality rates and decreased quality of life.[2] It is important to consider prognosis in the elderly when selecting optimal management of fragility fractures.

Historically, humeral shaft fractures have been primarily managed nonoperatively using a functional brace, which results in good functional outcome. Nevertheless, operative treatment for humeral shaft fractures has been increasing. Rämö et al. conducted a multicentre randomised control trial comparing operative with nonoperative treatment using a functional brace among patients with closed displaced humeral shaft fractures. They showed that upper extremity function was not significantly different in the two treatment groups at 12 months and that initial operative treatment provides a faster and more predictable course of recovery than nonoperative treatment. Among patients in the nonoperative treatment group, 30% underwent later operative treatment due to unforeseen adverse events, mainly nounions.[3] The increase in operative treatment can be attributed to the above advantages that have become apparent. However, it is unclear whether operative or nonoperative treatment is better in terms of life expectancy.

A prior study indicated that the overall 1-year mortality rate following humeral shaft fractures, comprising both pathological fractures and high-energy traumas, was 9.2%.[4] For proximal humeral fractures in the elderly, the 1-year mortality rate is 8.0%, according to Korean national data.[5] However, to the best of our knowledge, information regarding mortality following fragility fractures of the humeral shaft is limited, and factors associated with such mortality are unknown. In hip fractures, which are the most common fragility fractures, men, cardiovascular disorders, and kidney disease have been reported as factors associated with mortality.[6,7]

In this multicentre study, we aimed to show the mortality rate of humeral shaft fragility fractures (HSFF) in the elderly. Our secondary objective was to clarify the independent predictors of mortality among patients suffering HSFF.