ISPR8-0437/The abnormalities of the hip and knee joints in patients with posterior tibialis tendon dysfunction: Comparison with healthy age-matched controls

Abstract

Loss of the longitudinal arch and progressive hindfoot valgus are common clinical observations in the foot deformities of patients with posterior tibial tendon dysfunction (PTTD). The biomechanical abnormalities in patients with PTTD have been described, but few studies have investigated biomechanical chains of adjacent joints. Therefore, we examined the abnormalities of hip and knee joints through the gait analysis in subjects with PTTD. We compared 19 PTTD patients (average age: 67.1) with 30 age-matched control subjects (average age: 65.1). Subjects’ demographics was showed in Table 1 . Gait analysis was performed with a nine-camera motion-capture system and four force plates, using the VICON Plug-In-Gait and VICON Nexus software. Temporal-spatial parameters were compared between PTTD and control subjects, and joint angle and joint moment data were compared between the affected limb, the contralateral limb, and the right limb in control subjects. Subjects with PTTD had increased stance phase ratio and decreased stride length, cadence, and gait speed. The limbs of subjects with PTTD showed increased knee internal rotation at lording response, which was biased to abduction in the knee joint during the gait cycle, and irregular hip flexion and knee extension moment in the terminal stance, especially in the contralateral limb. We believe that the subjects with PTTD have an increased risk of knee osteoarthritis in both the affected and contralateral limbs.