Effect of Pain Severity on Quadriceps Isokinetic Peak Torque in Knee Osteoarthritis

Abstract

Objectives: to study the extent to which the pain severity in moderate knee osteoarthritis could affect the force production of the quadriceps in terms of eccentric and concentric isokinetic torque under different angular velocities. Methods: Sixty male patients diagnosed as moderate bilateral knee osteoarthritis according to Altman grade II were assigned to patient groups (group I; mild pain, group II; moderate pain and group III; sever pain) and twenty healthy subjects were assigned to healthy group. The peak torques of the eccentric and concentric contractions of the quadriceps at angular velocities of 40°/s and 120°/s in both knees were measured for all groups by using Biodex isokinetic dynamometer and pain severity was measured by using VAS. Results: A multiple measures analysis of variance revealed that there were no significant differences in the isokinetic peak torque values of quadriceps muscle between healthy group and group I in the following conditions; concentric contraction at angular velocity 120°/sec (p = 0.333) and eccentric contraction at both angular velocities 40°/sec (p = 0.158 ) and 120°/sec (p = 0.290). Otherwise, the isokinetic peak torque values of quadriceps muscle were significantly lower in group II and III in both concentric and eccentric contractions at both angular velocities. Conclusion Pain intensity has a negative uneven impact on isokinetic concentric and eccentric quadriceps peak torques in males with moderate knee osteoarthritis.