Association of Transversus Abdominis with gait speed in patients with hip osteoarthritis.

Abstract

Gait speed is a major determinant of daily function and quality of life in hip osteoarthritis, yet evidence on how trunk muscles are associated with gait is scarce. We investigated factors associated with gait speed in hip osteoarthritis, focusing on the transversus abdominis (TrA). Forty-nine women with hip osteoarthritis (64.2 ± 7.1 years) awaiting first unilateral total hip arthroplasty were enrolled. On the day before surgery, physical condition and function, including gait speed, gait pain, lower-limb strength, and TrA contraction ratio, were evaluated. To clarify which physical and functional variables are associated with gait speed, we entered gait pain, hip and knee-strength, TrA contraction ratio, age, Japan Orthopaedic Association stage for the hip on the unaffected side, leg length discrepancy and cane use during gait into a stepwise multiple-regression model with gait speed as the outcome. Stepwise regression showed that hip abductor strength on the unaffected side, cane use during gait, age, and the TrA contraction ratio were independently associated with gait speed (overall p < 0.001). The model explained 46 % of the variance in gait speed (R² = 0.463) and showed acceptable predictive accuracy (PRESS = 3.555; predicted R² = 0.347; large effect size f² = 0.862). Beyond lower-limb strength, cane use during gait and age, our findings show that TrA function is also associated with gait speed in hip osteoarthritis. This study demonstrates that TrA function is an independent correlate of gait speed in hip osteoarthritis and should be routinely assessed in clinical practice.