Background

Osteoarthritis and the pain associated with it result in gait pattern alteration, in particularly gait asymmetry when the disease is unilateral [1–2]. The quantification of such asymmetry could assist with the diagnosis and follow up. Various asymmetry indices have been proposed to compare the spatiotemporal, kinematic and kinetic parameters of lower limbs during the gait cycle. One, the Continuous Relative Phase [3] compares the joints angle and its derivatives to assess the gait asymmetry during the gait cycle. However, the indices rely on marker based gait measurement systems that are costly and generally require manual examination, calibration procedures and the precise placement of sensors/markers on the body of the patient.