Background/Purpose: Obesity is a risk factor for development of knee osteoarthritis due to altered gait biomechanics. Gait analysis was performed mostly on older obese adults with knee osteoarthritis. Biomechanics of young obese individuals is unclear. The aim of this study was to investigate the effect of obesity on gait biomechanics in young women; and the relationship between obesity and occurrence of knee osteoarthritis.

Methods: 31 healthy normal-weighted and 31 obese women aged between 30-45 years and body mass indexes (BMI) between 30-40 kg/m2 were included in this study. Anthropometric measurements like body weight (BW), height, waist/hip ratios were measured. Skinfold thickness (SFT) was measured from right side of the body. Isokinetic quadricesps and hamstring muscle strengths were measured at 60°/s angular velocity and 0-90° joint range of motion. Body composition analyses were determined before breakfast. Gait analyses were performed by Vicon 612 gait analyses system with the subjects’ comfortable walking speed.

Results: Mean age of obese group was 39.4 years and control group was 35.8 years (p˃0.05). Circumferences and SFT, body fat ratio, fat free mass (FFM) found higher in obese group (p«0. 001) and there was a strong relation between fat ratio and circumferences (r =0.89), BMI (r=0.85) and SFT (r=0.83). When peak torque were normalized to BW, Isokinetic quadricesps and hamstring muscle strengths were significantly lower in obese individuals (p<0.001). Walking speed, single support time, step length and stride length were lower and stance phase, double support time and step width was higher in obese individuals (p<0.001). In obese group we found that total excursion of pelvic obliquity, hip rotation and knee flexion-extension angle was lower (p<0.001), knee varus moment (p<0.05) and second peak of vertical ground reaction force was higher in obese group (p<0.001).

Conclusion: In obese subjects, isokinetic quadriceps and hamstring muscles strengths were lower, knee and hip joint range of motion was diminished. Knee peak varus moment and vertical ground reaction force at the end of stance phase were significantly higher in obese group. These results suggest that obesity may contribute to knee osteoarthritis. Thus, prospective studies are needed to identify the influence of higher loading rates on knee osteoarthritis.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/the-effect-of-obesity-on-walking-comparison-of-the-spatiotemporal-kinematic-and-kinetic-parameters-of-young-obese-and-non-obese-healthy-women/