Injury of the femoral nerve associated with acetabular fracture

Background: The purpose of the present study was to document the prevalence of, and recovery from, injuries of the femoral nerve associated with displaced acetabular fractures. Methods: From 1986 to 2001, 726 acetabular fractures were treated with open reduction and internal fixation. Four patients who had an injury of the femoral nerve associated with a displaced acetabular fracture were identified and were followed for a mean of 3.4 years. The nerve injury was iatrogenic in two patients and traumatic in two patients. Results: Clinically detectable quadriceps femoris motor function returned at an average of eighteen weeks (range, four to fifty-two weeks). All patients had satisfactory recovery of nerve function with a return of grade-4 or 5 motor power (the level of motor power needed to allow a normal gait) by an average of ten months (range, three to twentyfour months). Sensory recovery was incomplete but not debilitating. Conclusions: Preoperative examination of a patient who has an acetabular fracture should include an assessment of femoral nerve function. Regardless of whether the injury is traumatic or iatrogenic in origin, recovery of motor and sensory function without surgical exploration can be expected. Level of Evidence: Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence.