Body mass index moderates the association between gait kinetics, body composition, and femoral knee cartilage characteristics

This study compared femoral cartilage characteristics between age‐ and sex‐matched individuals with (n = 48, age = 22.8 ± 3.5 years; body mass index [BMI] = 33.1 ± 4.1 kg/m2) and without obesity (n = 48 age = 22.0 ± 2.6 years; BMI = 21.7 ± 1.7 kg/m2) and evaluated the associations between body composition, quadriceps function, and gait kinetics with femoral cartilage characteristics. Medial and lateral femoral cartilage thickness, medial:lateral thickness ratio and medial and lateral cartilage echo intensity were measured using ultrasound imaging. Body composition was assessed using air displacement plethysmography. Quadriceps function was assessed via maximal isometric knee extension. Three‐dimensional gait biomechanics were recorded to extract peak external knee flexion and adduction moments, and peak loading rate of the vertical ground reaction force. Cartilage outcomes were compared between groups using one‐way multivariate analysis of variance. Stepwise moderated regression evaluated the association between body composition, quadriceps function, and gait kinetics with femoral cartilage outcomes in individuals with and without obesity. Medial (75.24 vs 65.84; P