Functional outcomes and mortality vary among different types of hip fractures: a function of patient characteristics

A review of prospectively collected data was done to compare functional outcomes and mortality among patients with different hip fracture types. Five hundred thirty-seven elderly patients who sustained a hip fracture were followed up prospectively. Orthopaedists blinded to treatment and outcome radiographically classified the fractures as either: (1) nondisplaced or impacted femoral neck; (2) displaced femoral neck; (3) stable intertrochanteric; or (4) unstable intertrochanteric fracture. Functional independence measure scores were calculated for preinjury function and at 2- and 6- month follow-ups. Comorbidities, operative details, postoperative complications, and deaths were recorded. Six-month mortality was lowest for patients with nondisplaced femoral neck fractures (5.7%) and highest for patients with displaced femoral neck fractures (15.8%), but multivariate analysis only identified preinjury function as an independent predictor of mortality. All preinjury and followup functional independence measure scores were greatest for patients with nondisplaced femoral neck fractures and least for patients with unstable intertrochanteric fractures. However, multivariate analysis identified only patient age and preinjury functional independence measure scores as independent predictors of functional outcome. These data show differences in mortality and functional outcomes among fracture types that can be attributed to differences in functional status before injury.