Quantitative measurement of muscle atropy after ACL reconstruction

点击翻译按钮获取中文摘要

(1) Quantitative measurement of the quadriceps atrophy and herniation after the ACL reconstruction using the iliotibial tract were performed with the magnetic resonance image (MRI). 11 competitive level athletes were investigated. From the 15 axial slices of the MRI,muscle volume of all components of qurdriceps femoris and hamstrings were measured. The muscle volume of the vastus medialis showed 8% decrease comparing to the normal side. The spatial position of the quadriceps femoris rotated about 40ﾟ externaly comparing to the normal side. Though the largest external rotation occured at vastus lateralis, vastus medialis and intermedius also showed certain tendency of the excessive external rotation. At 60 and 180 deg/sec leg extension of the operated side showed 15% and 9% decrease of the peak torque in comparison with the control side.(2) Quantitative volume measurements of quadriceps femoris and hamstrings after ACL reconstruction were performed with the same MRI technique. 33 competitive or recreational level athletes who underwent ACL reconstruction with semitendinosus and gracilis tendons were investigated more than 1 year after the operatio. The muscle volume of quadriceps femoris and hamstrings showed 5-9% decrease in comparison with the control side. Though the tendinous portions were extirpated, the semitendinosus and gracilis muscles still preserved 60% and 71% of the control side volume, and exhibited muscle contraction at the Tagging Snapshot. There was no regeneration of the extirpated tendons. Slight hypertrophy of semimembranosus and biceps femoris muscle were observed in ha f of the cases. These morphological changes of thigh muscles were slightly related to the peak torque of knee extension and flexion.