Effect of Hip Adductors Isometric Contraction on Knee Extensors Isokinetic Torque in Patellofemoral Pain Syndrome

Abstract

Objective: To investigate if the isometric contraction of the hip adductors has an effect on the knee extensor peak torque either at 60⁰/s and 180⁰/s in patients with unilateral patellofemoral pain syndrome. Methods: 30 male and female aged 18-35 years old, the peak torque of the knee extensor muscles was measured by using the isokinetic dynamometer at the speeds of 60⁰/s and 180⁰/s. The isometric peak torque of hip adduction was measured by using handheld dynamometer. The visual analogue scale was used for pain level assessment. Results: The correlation between hip adduction isometric peak torque and concentric knee extension peak torque at 60⁰/s was weak negative non-significant correlation (r = -0.04, p = 0.82) and the correlation between hip adduction isometric peak torque and concentric knee extension peak torque at 180⁰/s was weak positive non-significant correlation (r = 0.08, p = 0.66). There was a significant decrease in pain without hip adductors isometric contraction at 180⁰/s compared with that at 60⁰/s (p = 0.001). Conclusions: There was no significant interaction between the effect of hip adductors isometric contraction and knee extensor peak torque at angular velocities 60⁰/s and 180⁰/s. There was no significant difference in pain between with and without hip adductors isometric contraction at 60⁰/s and 180⁰/s. There was a significant decrease in knee pain with and without hip adductors isometric contraction at 180⁰/s compared with that at 60⁰/s.