Quantify osteoarthritis gait at the doctor’s office: a simple pelvis accelerometer based method independent from footwear and aging

Abstract

The gold standard to evaluate the severity of steoarthritis in the doctor’s office remains clinical scores (Bellamy 2002). The Western Ontario and McMaster Universities (WOMAC) oste- oarthritis index is the most largely used score in rheumatology for lower limb osteoarthritis. It is based on clinical observation and it assesses pain, stiffness, and physical function in patients with hip and knee osteoarthritis. It is valid, reliable, and sen- sitive to evaluate osteoarthritis and adapted to doctor’s office (Bellamy 2002). However, clinical scores are inherently subjective and they depend from the patient’s impression and from the clinician’s interpretation. Gait analysis in modern gait laboratories with force plates and photogrammetry is a good tool to have an objec- tive, quantified, and precise insight in osteoarthritis (Astephen et al. 2008). For practical reasons, skin-mounted inertial sensors are well suited for investigating gait kinematics (Auvinet et al. 2002). In accelerometer-based gait analysis, aging is also known to affect gait parameters (Oberg et al. 1993). To have a clinical measure of osteoarthritis, it is essential to find a technique that is independ- ent from aging. Footwear can also affect walking parameters (Chambon et al. 2014). Since it is too time consuming to ask the patient to take off his shoe for the measurement, it is essential to find a method independent from the shoe type. Walking ten meters go and ten meters back on a level sur- face at comfortable walking speed is a well-suited protocol for clinical situations. This study proposes to test a 3D pelvis accelerometer-based measurement method on a group of 47 patients suffering from lower limb osteoarthritis and 12 asymptomatic subjects. The aim was to see whether the ccelerometer-based method is correlated with the clinical severity of the lower limb osteoarthritis evalu- ated with the WOMAC index. In addition, this study valuates whether the accelerometer-based method is independent of aging on 75 asymptomatic subjects and whether the acceler- ometer-based method is independent from footwear on one asymptomatic subject.