Residual shortening after Legg-Calve-Perthes disease, focusing on the response of the ipsilateral tibia.

Residual shortening of the affected limb was measured at skeletal maturity by teleoroentgenograms in 68 patients with Legg-Calve-Perthes disease (LCPD); special attention was paid to the length of the ipsilateral tibia. Of these 68 patients, 38 were treated by abduction orthosis (AO) and 30 by femoral varus osteotomy (FVO). Residual shortening in AO group was significantly greater than that in FVO group. The femoral lengths in both of these groups were similar (12.5 mm in the AO group and 10.1 mm in the FVO group), but the tibial lengths were significantly different (2.5 mm shortening in the AO group and 0.9 mm lengthening in the FVO group). Residual shortening in the patients treated by FVO was less than that in patients treated by AO. The difference is speculated to be caused by the overgrowth of the ipsilateral tibia.