Comparison of functional and conventional hamstring/quadriceps ratio in patients with knee osteoarthritis

  Introduction: As quadriceps (QC) and hamstring (H) work functionally in concentric and eccentric contraction pattern in the activities of daily living, it is necessary to evaluate functional H/Q ratio. The functional Hamstring/Quadriceps ratio (H/Q ratio) has not been investigated in the patients with knee osteoarthritis (OA). Therefore, we compared functional and conventional H/Q ratio in patients with knee osteoarthritis.   Materials and Methods: Thirty five patients with knee OA (21 females and 14 males 45-70 years old) were participated in this cross sectional study. Maximum torque of QC and H were evaluated during concentric and eccentric contraction (at 30°/s, 60°/s and 90°/s) and isometric contraction (at 30°,60° and 90° of knee flexion). Conventional H/Q ratio was calculated by maximum torque of H concentric or isometric contractions divided by maximum torque of QC concentric or isometric contractions. Functional H/Q ratio was calculated by maximum torque of H eccentric contraction divided by maximum torque of QC concentric contraction.   Results: The findings indicated that conventional H/Q ratio in compared with the functional H/Q ratio in lower angular velocity did not show significant difference statistically while this difference was significant in higher angular velocity. Higher significantly functional H/Q ratio was found in higher angular velocity (P< 0.005).   Conclusion: Considering that the daily activities and exercise therapy in patients with knee osteoarthritis are doing in lower velocity, not only the strengthening of quadriceps muscle but also quadriceps and Hamstring muscles balance should be noticed in exercise therapy of these patients. Also our findings showed functional H/Q ratio increased in higher angular velocity in patients with knee OA like normal subjects.