Avascular necrosis and nonunion after osteosynthesis of femoral neck fractures: effect of fracture displacement and time to surgery.

This study assessed the effect of fracture displacement and elapsed time before surgery on the development of avascular necrosis and nonunion after internal fixation of femoral neck fractures. Twenty-eight patients with 30 femoral neck fractures who underwent internal fixation and completed a minimum of 2 years' follow-up were retrospectively analyzed. The rates of avascular necrosis and nonunion were 12.5% and 25%, respectively, among patients who underwent surgery before 12 hours had elapsed and 14% and 27% among those who underwent surgery after that time. The rates of avascular necrosis and nonunion associated with fracture displacement were 6% and 18%, respectively, among patients with undisplaced (Garden stages 1 and 2) fractures and 23% and 38% among those with displaced (Garden stages 3 and 4) fractures. Nonunion and avascular necrosis led to the necessity for additional surgery in 11 of 30 (36%) hips. Internal fixation of femoral neck fractures is associated with a high initial complication rate, but if successful, the procedure ensures an excellent long-term outcome. Internal fixation should be considered the treatment of choice in young patients with nondisplaced fractures.