Total knee replacement (TKR) for the patients with degenerated joints and intractable pain has the rate of success over 80%. However, muscle wasting resulted from pain and disuse remained to be a function deficit after surgery. This study was to compare the muscle strength of involved and uninvolved knees for patients before and after unilateral TKR. Ten patients before and 13 patients post-6 month of unilateral TKR were included. Before surgery, the isometric peak torque were tested at 30 and 60 degrees of knee flexion. Both the peak torque of the flexor and extensor of the involved leg were significantly lower than the uninvolved side at 30 degrees of knee flexion (p<0.05). In contrast, only the extensor of the involved knee was significantly weaker than the uninvolved knee tested at 60 degrees of knee flexion (p<0.05). For patients post-6 month of operation, the extensor of the involved knee was significantly weaker than the uninvolved knee during isometric contraction at 30 or 60 degrees of knee flexion (p<0.05). However, the peak torque of flexor at either 30 or 60 degrees of knee flexion is hot significantly different between the uninvolved and involved knees. Isokinetic tests were also performed at post-operation follow-up. At the test speed of 120 and 180 degrees/sec, the peak torque of flexor and extensor of the operated knee were all significantly lower than the uninvolved leg (p<0.05). Furthermore, the hamstring/quadriceps (H/Q) ratio measured at post-6 month operation in 60 degrees of knee flexion in the involved knee is significantly higher than the uninvolved knee. This result is valuable in designing an effective strengthening program for patients after TKR. This result suggests that quadriceps strengthening and fast speed exercises for both flexor and extensor could be considered during the period of post operation.
Total knee replacement (TKR) for the patients with degenerated joints and intractable pain has the rate of success over 80%. However, muscle wasting resulted from pain and disuse remained to be a function deficit after surgery. This study was to compare the muscle strength of involved and uninvolved knees for patients before and after unilateral TKR. Ten patients before and 13 patients post-6 month of unilateral TKR were included. Before surgery, the isometric peak torque were tested at 30 and 60 degrees of knee flexion. Both the peak torque of the flexor and extensor of the involved leg were significantly lower than the uninvolved side at 30 degrees of knee flexion (p<0.05). In contrast, only the extensor of the involved knee was significantly weaker than the uninvolved knee tested at 60 degrees of knee flexion (p<0.05). For patients post-6 month of operation, the extensor of the involved knee was significantly weaker than the uninvolved knee during isometric contraction at 30 or 60 degrees of knee flexion (p<0.05). However, the peak torque of flexor at either 30 or 60 degrees of knee flexion is hot significantly different between the uninvolved and involved knees. Isokinetic tests were also performed at post-operation follow-up. At the test speed of 120 and 180 degrees/sec, the peak torque of flexor and extensor of the operated knee were all significantly lower than the uninvolved leg (p<0.05). Furthermore, the hamstring/quadriceps (H/Q) ratio measured at post-6 month operation in 60 degrees of knee flexion in the involved knee is significantly higher than the uninvolved knee. This result is valuable in designing an effective strengthening program for patients after TKR. This result suggests that quadriceps strengthening and fast speed exercises for both flexor and extensor could be considered during the period of post operation.