Evaluation of functional results of surgical treatment in children with Legg-Calve-Perthes disease using a portable gait analysis system

Introduction Typical consequences of Legg-Calve-Perthes disease (LCPD) in its severe stage are pathological changes in the anatomy of the hip joint which lead to functional disorders of the musculoskeletal system, clinically manifested by limp. Objective To study biomechanical characteristics of walking in children with unilateral Legg-Calve-Perthes disease to determine the functional state of the musculoskeletal system after surgical treatment with the use of various methods. Material and methods Temporal and dynamic parameters of gait were studied in 31 patients with unilateral Legg-Calve-Perthes disease aged from 8 to 13 years old. They were examined two to five years after surgical treatment. In the control group of patients (15 children), varus osteotomy (VO) was performed. In the main group (16 children), triple pelvic osteotomy (TPO) was used. All children were operated in the disease stages II-IV corresponding to the classifications of S.A. Reinberg (1964) and to groups III-IV according to the classification of Catterall (1971). To objectify the study, 18 healthy children of the same age without signs of orthopaedic pathology were examined. Gait biomechanics were studied using the STEDIS complex (Neurosoft LLC, Ivanovo) that includes a set of platformless inert sensors "Neurosens" that record the data on accelerations in three mutually perpendicular planes. The temporal characteristics of the gait cycle and shock loads during walking were recorded. Results After surgical treatment, the biometrics of the support and shock load phases in both groups of children with LCPD did not reach the level of healthy individuals. It indicates preservation of deviations in walking parameters. The least significant asymmetry between the affected and unaffected limb were detected in patients after TPO, compared with patients after VO in whom the asymmetry of temporal parameters in the phase of the forefoot rocker and asymmetry of shock loads in the phases of rocking over the heel and ankle joint were preserved. Conclusion After ТPO operations in patients with LCPD, the gait was closer to the physiological one in comparison with patients after VO who retained a non-optimal motor stereotype. The reasons for such differences in motor activity between the groups of patients lies in the gluteal muscle dysfunction due to high position of the greater trochanter after corrective (varus) femur osteotomy and iatrogenic shortening of the affected limb. Triple pelvic osteotomy lacks these negative effects.