Radiographic analysis of the Brooker-Wills interlocking nail in the treatment of comminuted femoral fractures.

Forty-three patients with 43 comminuted femoral shaft fractures treated with the Brooker-Wills interlocking nail were followed through bony union to determine the device's ability to maintain length and rotational control of these difficult injuries. Only severely comminuted fractures, types III and IV, were included. Implant complications were also studied. Average shortening for type III and type IV fractures measured 0.43 and 0.51 cm, respectively. Overall average shortening measured 0.47 cm (range, 0.0-2.2 cm). Maximal shortening occurred in a 72-year-old osteopenic female. Six of the 23 femurs stabilized with the smaller 13- and 14-mm-diameter nails shortened more than 1.0 cm, whereas lesser degrees of shortening tended to occur with larger-diameter implants. The proximal locking diagonal screw provided adequate proximal control and was never found to be the cause of fracture shortening. Rod deformation occurred in nine patients (21%) and was seen only in 13.0- and 14.0-mm-diameter rods. The distal lock was found to control rotation clinically but played only a minor role in preventing shortening. Distal shortening appeared to be controlled by bone-rod contact at the metaphysis, as nailings within 0.5 cm of the epiphyseal scar resulted in the least amount of shortening. Although this intramedullary device produced adequate clinical and radiographic results in comminuted femoral shaft fractures in the young, multiply injured patient, we caution against the use of the 13.0- and 14.0-mm implants. In addition, the efficacy of this implant is unproved in the osteopenic patient.