Femoral sulcus angle measurements

We sought to determine whether the femoral sulcus angle measurement is consistent on different radiographic projections of the knee. Seventy-four cadaveric knees were radiographed using Merchant, Laurin, and Hughston projections. The measurements of the sulcus angle (mean, 138.6 degrees; SD, 6.9 degrees; and range, 120 degrees to 155 degrees) obtained with the Merchant technique were similar (P = 0.0007) to those obtained with the Hughston (mean, 137.4 degrees; SD, 7.6 degrees; range, 122 degrees to 155 degrees) and Laurin (mean, 141.6 degrees; SD, 6.9 degrees; and range, 125 degrees to 162 degrees) projections. Therefore, we submit that either the Hughston or Laurin view can be used instead of the Merchant view to reliably measure the femoral sulcus angle.