Atrophy of thigh muscles after meniscal lesions and arthroscopic partial menisectomy.

The purpose of this study was to investigate the atrophic pattern of the muscle groups and their individual muscles in the thigh after meniscal lesions and arthroscopic partial menisectomy. A total of 32 individuals (17 men and 15 women) who underwent arthroscopic knee surgery participated in this study. Their operated and non-operated thighs were scanned by magnetic resonance imaging to determine the volume of the quadriceps (QF), hamstring (HM), and adductors (AD). Compared with the non-operated limb, the volume of the QF was significantly lower in the operated limb; however, no significant difference was observed in the HM and AD. The volume of individual muscles of the QF, i.e. the rectus femoris (RF), vastus lateralis (VL), vastus intermedius (VI), and vastus medialis (VM), in the operated limb was significantly lower than the volume of those in the non-operated limb (P<0.01, all). Although the relative change in the VM was significantly higher than that of the RF (P<0.05), specific atrophy was not found among four individual muscles in the QF. We concluded that meniscal lesions and partial menisectomy induce atrophy in the QF only in the thigh, and that no specific atrophy, e.g. VM, seemed to occur within the individual muscles in the QF.