The purposes of this retrospective study was to document peak torque of knee muscles and the ratio of hamstrings to quadriceps at initial evaluation in the patients following anterior cruciate ligament (ACL) reconstruction; and to evaluate the improvement of isokinetic strength of knee muscles after rehabilitation. There were 17 subjects, aged 20-year-old to 37-year-old (mean, 23.9-year-old), who had undergone ACL reconstruction with patella tendon graft and received rehabilitation program including hot packing or hydrotherapy, ROM exercise and strengthening exercise using isokinetic dynamometer at National Taiwan Universty Hospital. The muscle strength of bilateral quadriceps and hamstrings were assessed with CybexⅡ+ isokinetic dynamometer at the speed of 60, 120, 180, 240 degrees/sec before and after receiving rehabilitation programs for 1-3 months. The results revealed that, in the postoperative knees, there are significant difference from sound side in the deficiency of the peak torque (the extensor deficits were around 50-60%, flexor deficits around 20-40%) and the ratio of hamstrings to quadriceps in the first evaluation was higher than the sound side; but the deficiency shows no significant difference in patients grouped by the time of receiving first assessment first evaluation taken in 3 months post-operation, in 3-6 months post-operation and after 6 months post-operation). However, the percentage of improvement of muscle strength in the group of patients who received rehabilitation program in postoperatively 3 months were significantly greater than those who received rehabilitation program after 3 months postoperatively. The study suggests that the muscle strength of quadriceps and hamstrings show significant weakness following ACL reconstruction, and early rehabilitation program is important for these patients to get more efficiency in recovery of knee muscle strength.
The purposes of this retrospective study was to document peak torque of knee muscles and the ratio of hamstrings to quadriceps at initial evaluation in the patients following anterior cruciate ligament (ACL) reconstruction; and to evaluate the improvement of isokinetic strength of knee muscles after rehabilitation. There were 17 subjects, aged 20-year-old to 37-year-old (mean, 23.9-year-old), who had undergone ACL reconstruction with patella tendon graft and received rehabilitation program including hot packing or hydrotherapy, ROM exercise and strengthening exercise using isokinetic dynamometer at National Taiwan Universty Hospital. The muscle strength of bilateral quadriceps and hamstrings were assessed with CybexⅡ+ isokinetic dynamometer at the speed of 60, 120, 180, 240 degrees/sec before and after receiving rehabilitation programs for 1-3 months. The results revealed that, in the postoperative knees, there are significant difference from sound side in the deficiency of the peak torque (the extensor deficits were around 50-60%, flexor deficits around 20-40%) and the ratio of hamstrings to quadriceps in the first evaluation was higher than the sound side; but the deficiency shows no significant difference in patients grouped by the time of receiving first assessment first evaluation taken in 3 months post-operation, in 3-6 months post-operation and after 6 months post-operation). However, the percentage of improvement of muscle strength in the group of patients who received rehabilitation program in postoperatively 3 months were significantly greater than those who received rehabilitation program after 3 months postoperatively. The study suggests that the muscle strength of quadriceps and hamstrings show significant weakness following ACL reconstruction, and early rehabilitation program is important for these patients to get more efficiency in recovery of knee muscle strength.