Postural control in assessing the effectiveness of motor recovery following total hip arthroplasty

Introduction Postural control (PC) is a predictor of gait recovery and can be performed in the early postoperative period following total hip arthroplasty (THA) for adequate appraisal of the treatment and recovery of orthopedic patients. The search for PC markers is practical for relevant evaluation of the effectiveness of motor rehabilitation following THA of one (contralateral) hip or both joints. The objective was to establish specific features of PC assessing effectiveness of motor rehabilitation in patients with hip osteoarthritis after unilateral and bilateral THA. Material and methods A total of 40 patients with grade III–IV hip osteoarthritis were examined as Group 1 (n = 21) with unilateral THA of the contralateral hip joint and Group 2 (n = 19) with bilateral THA. The PC was assessed using an inertial sensor placed at the L4–L5 projection to record angular and spectral parameters of postural fluctuations from the vertical in the coronal and sagittal axes. Examinations were performed on admission and upon discharge after a course of motor rehabilitation in the inpatient medical rehabilitation department. Results Improvements in the PC during the inpatient rehabilitation were accompanied by greater deviations in the coronal plane and less deviations in the sagittal plane in the unilateral THA group suggesting frontal instability. There was no increase in frontal axis deviations with sagittal deviations being maintained in the bilateral THA group. Models for predicting the effectiveness of motor recovery were offered. Discussion Objective indicators of the PC in patients with hip osteoarthritis treated with unilateral or bilateral THA, were obtained with inertial sensor technology and could be used to identify compensatory musculoskeletal mechanisms, determine markers of the effectiveness of rehabilitation and adjust recovery programs. Conclusion Motor rehabilitation of THA patients suggests that bilateral arthroplasty destabilizes the biomechanics of the hip joint to a lesser extent, limiting excessive deviations in the frontal plane and slows down restoration of statokinetic stability due to proprioceptive insufficiency.