Gait Biomechanics

The Influence of Body Mass Index and Sex on Frontal and Sagittal Plane Joint Moments During Walking.

Obesity and female sex are considered independent risk factors for the development of knee osteoarthritis (KOA) which may be due to aberrant gait biomechanics. Few data exist on the interaction of obesity and female sex despite their independent influence on KOA risk. The purpose of this study was to examine the influence of sex and BMI on knee joint sagittal and frontal plane gait mechanics. Dependent variables included the knee flexion moment (KFM) and first peak knee adduction moment (KAM1). Gait biomechanics were assessed in 42 obese and 39 normal weight participants that were matched on age and sex. Kinematic and kinetic data were sampled using a 9-camera Qualisys system and 2 AMTI force-plates. Participants completed walking trials in laboratory standard neutral-cushion footwear at self-selected speed and the external KFM and KAM1 during the first 50% of stance was extracted and normalized to a product of bodyweight (N) and height (m). A 2 (BMI) by 2 (Sex) analysis of co-variance (α=0.05) was used to examine dependent variables with gait speed as a covariate. The BMI by sex interaction was not significant for KFM (p=0.073) or KAM1 (p=0.703). A main effect was observed for sex and females exhibited smaller KFM (p=0.05) and greater KAM1 (p=0.004) compared to males. No differences were found in normalized knee moments between BMI groups. Regardless of BMI, females exhibited aberrant gait mechanics that are indicative of KOA progression. Further studies are needed examining the influence of altered gait in young, healthy females on knee cartilage morphology.
Listed In: Biomechanics, Gait