To prospectively compare the results, function, and complications of antegrade and retrograde femoral nailing for femoral shaft fractures.

Prospective, randomized.

Urban Level 1 trauma center.

One hundred consecutive femoral shaft fractures. Fifty-four nails inserted retrograde and forty-six inserted antegrade.

Ten-millimeter antegrade or retrograde nail inserted for a femoral shaft fracture after reaming.

A comparison of the outcomes after antegrade and retrograde nailing of the femur. Data were collected for analysis on comminution, set-up and starting point times, open grade, location of fracture, injury severity score, body mass index, time to union, knee pain and motion, hip and thigh pain, and nail to intramedullary canal diameter difference. A linear regression model was employed.

Knee motion was 120 degrees in all but one knee in each group. The antegrade nailed femurs healed faster than those treated retrograde (A = 14.4, R = 18.1 weeks, p = 0.0496). More patients required dynamization for union in the retrograde insertion group (17 percent versus 5 percent, p = 0.10, NS). In a linear regression model, a nail-to-canal-diameter difference and retrograde nailing had an association with an increased time to union. Knee pain was equal in both groups; however, thigh pain was higher in the antegrade group (p = 0.0108). All of the antegrade nailed femurs healed (100 percent), and 98 percent (one nonunion) of the retrograde femurs healed after secondary procedures.

Both antegrade and retrograde nailing yielded high union rates. Each insertion technique has its own advantages and disadvantages. The two insertion modes appear to be relatively equal for the treatment of femoral shaft fractures.