Superior migration of the femoral head in patients with severe hip osteoarthritis influences the gait patterns of the coronal plane

Introduction:Patients with hip osteoarthritis (OA) show abnormal movement patterns, including the leaning of the trunk toward the affected limb (Duchenne limp). Patients with severe OA, especially those with OA due to hip dysplasia, show a lateral pelvic drop (Trendelenburg sign).Aim:The aim of this preoperative study is to investigate the relationship between superior migration of the arthritic femoral head, pain, and hip abductor muscle strength, and to clarify the relationship between the coronal plane gait patterns with pain and hip abductor muscle strength.Methods:The subjects of this study were 18 patients with unilateral hip OA secondary to dysplasia. A radiographic analysis was performed on standardised anteroposterior pelvis films. The abductor muscle strength of the OA hip joint was measured with a handheld dynamometer. The tilt angle of the pelvis and trunk lean angle during gait were obtained using a 3-dimensional motion analysis system. Visual analogue scale (VAS) of pain was obtained after t...