The Impact of Insurance Status on the Development of Nonunion following Scaphoid Fracture.

Purpose  Certain factors have been associated with the development of scaphoid nonunion, including delayed diagnosis, smoking, inadequate initial management, proximal location, and carpal instability. We hypothesized that insurance status would also be a risk factor for the development of scaphoid nonunion. Methods  A case-control study was performed on patients who presented to a single surgeon at a tertiary referral center during 2006 to 2015. Cases were patients presenting with nonunions, controls, and patients with acute fractures. Patients were characterized as underinsured if they lacked any type of insurance or if they were on Medicaid. Results  Patients (39 nonunions [cases] and 32 primary fractures [controls]) presenting with nonunions were more likely than controls to have had displaced fractures (72 vs. 41%) and fractures located at the proximal aspect of the scaphoid (18 vs. 0%), and to be underinsured (46 vs. 19%). Conclusion  Patients presenting with nonunions were more likely to be underinsured than patients presenting with primary fractures. This finding suggests that underinsurance is a risk factor for the development of nonunion. Assuming delay between fracture and intervention is a known risk factor for the development of nonunion, and it is likely that the association between nonunion and underinsurance is mediated through this delay. Level of Evidence  Prognostic, level III, case-control study.