Fluoroscopic measurement of tibial torsion in adults. A comparison of three methods.

Three methods based on the fluoroscopic technique for measurement of tibial torsion were analyzed. The measurements were performed bilaterally in 100 normal adults. The values for bilateral tibial torsion were recorded and the values for the difference in torsion between the right and left tibia were calculated. The standard error of all investigated methods was found to be lower than published figures for computerized tomography and ultrasonic methods. The method found to be most convenient for routine use also presented the best repeatability. With this method, the standard error of a single determination of tibial torsion was estimated to be 0.7 degrees.