A comparison of modified Knowles pins and cannulated cancellous screws for the treatment of nondisplaced or impacted femoral neck fractures.

A prospective study was performed comparing modified Knowles pins to cannulated cancellous screws for the treatment of nondisplaced and impacted femoral neck fractures. Forty-five impacted or nondisplaced fractures were identified: twenty-five were stabilized with modified Knowles pins and twenty with cannulated cancellous screws. Patient follow-up averaged twenty-four months (range 12 to 46 months) or until reoperation. Six patients (13%) required reoperation; these failures were evenly divided between the two groups. The remainder of patients (twenty-two patients (88%) in the Knowles pin group and seventeen patients (85%) in the cannulated screw group) were comparable with regard to functional outcome.