Foot biomechanics in patients with advanced subtalar- and Chopart joint osteoarthritis and poorly responding to conservative treatment

Abstract

Abstract Background A comprehensive insight into the effects of subtalar- and Chopart joint osteoarthritis on lower limb’s biomechanical characteristics during walking is lacking. Our goal was to assess joint kinematics and kinetics and compensatory mechanisms in patients with subtalar and Chopart joint osteoarthritis. Methods Patients with symptomatic and radiographically confirmed osteoarthritis of the subtalar and Chopart joint (n = 10) and an asymptomatic control group (n = 10) were compared. Foot joint kinematics and kinetics during the stance phase of walking were quantified using a four segment foot model. Results During pre-swing phase, the Ankle range of motion in the sagittal plane of the patient group decreased significantly (P = 0.001), whereas the Lisfranc joint range of motion in the sagittal plane was greater in the pre-swing phase (P = 0.003). The Chopart joint showed lower transverse plane range of motion in the patient group during the loading response and pre-swing phase (P < 0.001 resp. P = 0.002). The patient group showed a lower Ankle peak plantarflexion moment (P = 0.004), peak plantarflexion velocity (P < 0.001) and peak power generation in the sagittal plane (P < 0.001), and a lower Chopart joint peak adduction and abduction velocity (P < 0.001 resp. P < 0.001) and peak power absorption (P < 0.001). Conclusions These findings suggest that patients with subtalar and Chopart joint osteoarthritis adopt a cautious walking strategy potentially dictated by pain, muscle weakness, kinesiophobia and stiffness. Since this poorly responding population faces surgical intervention on the short term, we recommend careful follow-up after fusion surgery since biomechanical outcome measures associated to this post-surgical stage is lacking.