Leg Length Discrepancy Assessment: Accuracy and Precision in Five Clinical Methods of Evaluation

Five clinical methods of leg length discrepancy assessment were tested against one another for their relative accuracy and precision compared to exact anatomical standards as determined by radiograph. Five normal subjects, one with a known discrepancy of 1.3 cm, were evaluated by twenty physical therapists each using every method of assessment. T-tests and F-tests (a = 0.05) were used to determine statistical accuracy and precision among methods. Absolute values of mean differences, standard deviations, and ranges were used to determine clinical significance. The indirect method, which employed lift blocks under a foot with a subject in the standing position, proved to be the most accurate and precise method of any tested. Of the direct methods tested, which employ a tape measure between various anatomical landmarks, the technique shown to be the most accurate and precise utilized the landmarks of the anterior superior iliac spine and the lateral malleolus of the fibula.J Orthop Sports Phys 1984;5(5):230-239.