Evaluating the impact of strabismus surgery on the association of musculoskeletal injuries, fractures, and falls with disorders of binocular vision in medicare beneficiaries

Disorders of binocular vision that are increasingly prevalent among aged, fee-for-service Medicare beneficiaries are associated with fractures, falls, and musculoskeletal injuries. We evaluate whether strabismus surgery influences the association of injuries in elderly patients with disorders of binocular vision in a 5% random sample of Medicare fee-for-service claims data from 2010 to 2013. There were 22,237 Medicare beneficiaries with a claim that included a diagnosis of a disorder of binocular vision. Of these, the majority had strabismus (49.5%); amblyopia (9.14%), diplopia (53.5%), and nystagmus (2.72%) were also represented. There were 530 patients who underwent strabismus surgery. The unadjusted odds ratio for the association between undergoing strabismus surgery and any of the three musculoskeletal injuries defined above was 0.868 (95% CI, 0.725-1.040; P = 0.13), and the adjusted odds ratio was 1.004 (95% CI, 0.833-1.210; P = 0.97). This study did not reveal a difference in the subsequent risk of musculoskeletal injuries, fractures, or falls in Medicare beneficiaries who underwent surgery. The failure to find an association could represent a true lack of correlation, selection bias, study design using administrative claims data, or a very small effect.