A technical tip for assessing leg length discrepancy in radiographs with windswept hips.

Restoration of equal leg lengths is essential when performing total hip arthroplasty. Pre-operatively, surgeons should assess leg length discrepancy (LLD) on plain radiographs to help adequately plan their operation. Often the hips are in a minor windswept position on radiographs and this can make assessing LLD unreliable. We have devised a simple method for assessing LLD on plain radiographs in patients with windswept hips.