Development of gait performance and dynamic hip and knee joint loading after containment improving surgery in patients with Legg-Calvé-Perthes disease

•Long-term gait characteristics in LCPD following containment improving surgery.•Restricted flexion/extension ROM at the knee during gait compared to controls.•“Stiff knee gait pattern” as compensatory mechanism for leg length discrepancy.•Normalization of sagittal plane hip angles and trunk movement during gait.•Knee and hip joint loading during gait normalized during the postoperative period.

Current surgery outcome evaluations in patients with Legg-Calvé-Perthes disease (LCPD) are usually based on static radiological changes. The aim of the present study was to assess the development of characteristic gait parameters and passive hip range of motion (ROM) measurements during the postoperative period up to healed stage of the femoral head represented by Stulberg classification. Twelve children (10 male, 2 female) with unilateral diagnosis of LCPD and 19 healthy control subjects at the same age participated in this prospective longitudinal study. Instrumented gait analysis was performed preoperatively, 13.4 (±1.7), and 28.0 (±4.4) months postoperatively. At final follow-up, the mean leg length of the involved side was reduced by 1.10 (±0.53) cm compared to the non-involved side. In addition, a significant reduction in maximum knee flexion (−26%, p = 0.037) and knee flexion/extension ROM (−26%, p = 0.017) in stance was still present in the patient group compared to controls indicating a “stiff knee gait pattern”. In contrast, the sagittal plane hip parameters, the ipsilateral trunk lean toward the involved stance limb, and the knee and hip joint loading during gait normalized during the postoperative period. The results of the present study should motivate further exploration if patients with LCPD stiffen their knees to compensate for leg length discrepancy. Besides the standard radiological evaluation of the surgery outcome, instrumented gait analysis is a valuable method of recording functional deficits and early recognition of the need for physiotherapeutic treatment or insole supply in patients with LCPD.