Effect of intensive conservative therapy on gait performance in patients with legg-calvé-perthes disease

Abstract

Introduction: The hip joint may develop early osteoarthritis in patientswithPerthesdisease [1]. Physical examinationoften shows a limitation in range of motion (ROM) for hip extension, abduction and internal rotationaswell as anabductorweakness [2]. Conservative therapeutic training is an alternative to surgical interventions that can be used to improve altered biomechanics of the hip.While mechanisms of gait compensation in these patients have beenwell described [3], there is a lack of research on the effects of therapeutic training on gait performance. The purpose of the present study was to evaluate whether physiotherapy treatment could improve gait parameters in patients with Perthes disease. Patients/materials and methods: 18 patients with unilateral Perthes disease and a mean age of 6.2 (±1.9) years participated in this prospective study. Gait analysis was performed immediately before and 12 weeks after intensive therapeutic training. Kinematic datawere collected using an eight-cameraVicon system.One force plate (AMTI) was used to calculate mechanical power. The Helen Hayesmarker set [4] was applied to determine joint centers. All subjects walked barefoot at a self-selected speed along a 15m walkway. Differences were tested for significance using a paired ttest (significance level was set at P<0.05). The absolute symmetry index (ASI) was determined on the basis of the symmetry index of Robinson et al. [5]. Results: The thorax obliquity ROM was significantly decreased and hip power generation was significantly increased for the affected side during stance phase after therapeutic training. Moreover, the ASI showed a tendency toward an increasing symmetry between the affected and unaffected side for spatio-temporal parameters. In the clinical evaluation, the passive hip flexion increased significantly. However, the significantly decreased hip extension/flexion ROM of the affected side compared to the unaffected side did not change after therapeutic training during walking. Discussion& conclusions: These results suggest that therapeutic training can improve gait symmetry. In addition, as a result of the reduced Duchenne gait pattern, the mechanical energy generation by the hip extensors was increased. However, the decreased hip ROM in the sagittal plane did not change during walking after a therapeutic training period of 12 weeks. In order to avoid longterm gait impairment, sagittal hip flexibility should be taken into account andwas also observedduring thephysiotherapy treatment period. Therefore, gait analysis can be used to objectively evaluate the functionality of the involved joint, to indicate the discrepancy between passive ROM and dynamic situations as well as for potentially therapeutic treatment modification.