The accessory bands of Gracilis and Semitendinosus: an anatomical study

Arthroscopic anterior cruciate ligament (ACL) reconstruction using Semitendinosus and Gracilis tendons is a popular technique for the treatment of ACL deficient knees. It is common to find accessory tendinous bands arising from these two tendons when harvesting them. The implications are that extra care must be taken with the use of the tendon stripper if one is to avoid cutting the main tendon. Our aim was to map these accessory bands and assess their variability using a cadaveric model. In particular we were interested to identify the presence of bands arising proximally beyond 10 cm. We dissected the tendons of Gracilis and Semitendinosus of 10 embalmed adult human cadaveric legs. We found that accessory bands have a high variability. Bands were seen between tendons, connecting them to the popliteal fascia, Sartorius, Gastrocnemius, pre-tibial and superficial fascia. Accessory bands originated more than 10 cm proximally from Semitendinosus and Gracilis in 8 and 2 occasions, respectively. There was a constant connection band between Semitendinosus and the Gastrocnemius fascia. Our results confirm that the anatomy of accessory bands is more variable than previously reported. Surgeons should be aware of our new finding of bands commonly originating beyond 10 cm proximally.