Anatomical and morphological variations in the tendons constituting the pes anserinus of knee with its clinical significance: A human cadaveric study

Context: Pes anserinus (PA) includes conjoined tendinous insertion of the sartorius, gracilis, and semitendinosus muscles. Each tendon can have individual insertions attached nearly in a linear arrangement. The presence of accessory tendons, bands, and structures constituting in forming PA shows high variability and has been reported clinical importance in harvesting PA graft and tendon reconstruction procedure. Aim: The present study aimed to macroscopically observe anatomical and morphological variations in the structures constituting in the insertion of the PA tendon and establish its clinical significance. Subjects and Methods: A total of ninety cadaveric lower limbs including both sexes dissected to observe variations in the structures forming PA at the anteromedial surface of the upper part of the tibia. Statistical Analysis Used: The descriptive statistical analysis was done. Results: PA was constituted of sartorius, gracilis, and semitendinosus tendons in all the specimens. The most common pattern observed was monotendinous-sartorius, gracilis, and semitendinosus in 67 (74.44%) limbs. The semimembranosus and tibial collateral ligament participation was observed in 5 (5.55%) and 2 (2.22%) limbs, respectively. The accessory band of sartorius and semitendinosus was observed in 2 (2.22%) and 14 (15.55%) limbs, respectively. Conclusions: PA in the medial side of the knee is a common injury site. The presence of any accessory structures or bands within can handicap graft harvesting since the gracilis and semitendinosus tendons are routinely harvested for the reconstruction procedure. Furthermore, present anatomical knowledge can be helpful to surgeons for preoperative radiological examination and to avoid complications during transplant graft surgeries of the knee.