Quadriceps Impairment Is Associated with Gait Mechanics in Young Adults with Obesity

Abstract

Purpose Obesity influences gait and muscle function, which may contribute to knee osteoarthritis. This study aimed 1) to compare gait biomechanics and quadriceps function between individuals with and without obesity and 2) to examine the association between quadriceps function and gait biomechanics. Methods Forty-eight individuals with and 48 without obesity participated and were matched on age and sex. Gait biomechanics at standardized and self-selected speeds were used to assess peak vertical ground reaction force (vGRF), vertical loading rate (vLR), internal knee extension moment (KEM), peak knee flexion angle (KFA), knee flexion excursion (KFE), and knee joint stiffness. Quadriceps function was assessed using peak isometric strength (peak torque), early (RTD100) and late (RTD200) rate of torque development (RTD), and vastus lateralis cross-sectional area (CSA) and echo intensity (EI). Results When normalized to fat-free mass, individuals with obesity had lower RTD100 (P = 0.04) and RTD200 (P = 0.02) but higher vastus lateralis CSA (P < 0.01) and EI (P < 0.01) compared with normal weight controls. The group–speed interaction was significant for normalized vGRF (P < 0.01), normalized vLR (P = 0.02), normalized KEM (P = 0.03), and normalized knee joint stiffness (P = 0.02). Post hoc analyses indicate a smaller normalized vGRF and normalized KEM, and lower knee joint stiffness in individuals with obesity compared with normal weight controls at self-selected speed. There were main effects of speed for all kinematic and kinetic variables, and body mass index group for all absolute kinetic variables as well as normalized vGRF (all P < 0.001). A lower vastus lateralis EI (P = 0.04) and greater RTD100 (P < 0.01) were associated with a larger KEM in individuals with obesity. Conclusion Individuals with obesity have quadriceps dysfunction that is weakly associated with KEM during walking. Exercise interventions that improve quadriceps function may improve walking mechanics.

Quadriceps Muscle Size, Quality, and Strength and Self-Reported Function in Individuals With Anterior Cruciate Ligament Reconstruction

“…Conversely, quadriceps CSA and EI contributed to functional ability in young adults with obesity, older adults, and individuals with KOA. 17,19,33 In individuals with KOA, greater quadriceps intramuscular fat was associated with greater disease severity and less strength. 19 Similarly, greater thigh muscle fat infiltration was associated with higher odds of mobility limitations independent of muscle size and strength in older adults.…”

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

“…A value of 1 cm was substituted for the value of x (subcutaneous tissue thickness) to obtain a correction factor, and thus, the correction factor represents the addition of echo intensity for every 1.0 cm of subcutaneous tissue thickness using the average slope and y-intercept Marker trajectories and force plate data were low-pass filtered at 5 and 50 Hz following residual analyses, respectively, using a zero-phase-lag fourth-order Butterworth filter. 9,32 Filter parameters were selected to retain the heelstrike transient associated with high loading rates in adults with obesity, 32,33 and unmatched low-pass filter cutoffs have minimal influence on joint moments during walking. 34 External joint moments were calculated using inverse dynamics 35 and normalized to a product of body weight and height.…”

“…For example, individuals with obesity have higher absolute but smaller external knee flexion moments compared with controls when scaled to anthropometrics. 9 The external knee flexion moment contributes to greater patellofemoral contact force. 10 Furthermore, a reduced knee flexion moment is indicative of a quadriceps avoidance gait pattern that is common in adults with knee OA.…”

“…11 The quadriceps act eccentrically to control knee flexion during gait and attenuate ground reaction force (GRF). Consequently, adults with obesity have lower quadriceps rate of torque development (RTD), 9 and higher vertical GRF loading rates compared with controls. 12 While many studies have evaluated the association between gait and cartilage outcomes in patients with knee OA, few studies have examined these relationships in young adults with obesity, 5 despite their high risk for knee OA.…”

Longitudinal Assessment of Quadriceps Muscle Morphology Before and After Anterior Cruciate Ligament Reconstruction and Its Associations With Patient-Reported Outcomes

“…7,10 In fact, patients with knee osteoarthritis, who demonstrate quadriceps muscle weakness similarly to ACLR patients, have a higher proportion of intramuscular PF compared with healthy controls. 8,12,17 Given that quadriceps muscle size and quality are associated with overall muscle strength, patient-reported function, quality of life, and functional ability in young healthy adults, 14,23 individuals with obesity, 40 and the elderly, 8,31,37 it seems plausible that a similar relationship may exist in patients after ACLR. Therefore, further study on postoperative alterations in quadriceps size and quality (ie, intramuscular fat content) may expand our understanding of potential contributors to poor patient outcomes after ACLR.…”