The anatomy and morphometry of the proximal semimembranosus muscle tendon - a cadaveric study with clinical implications.

INTRODUCTION

The semimembranosus muscle (SM) is a key component of the posterior thigh and an integral part of the hamstring group. It plays a crucial role in lower limb movement, particularly in knee flexion, hip extension, and medial rotation of the tibia (with the knee flexed), in cooperation with other muscles of the hamstring complex. The aim of this study was to assess the anatomy and morphometry of the SM proximal tendon.

MATERIALS AND

METHODS

The proximal tendon of the semimembranosus muscle was carefully dissected and examined in 60 cadaveric specimens (32 left and 28 right) obtained from 60 cadavers (27 females and 33 males).

RESULTS

During dissection, one tendon variant was identified on the medial side, whereas two tendon variants (Type I and Type II) were distinguished on the lateral side. Type I was observed in 42 specimens, while Type II was identified in 18 specimens. Morphometric parameters, including the lateral and medial lengths of the superficial part of the SM tendon, the lateral and medial lengths of the deep part of the tendon, as well as tendon thickness and width, were measured in detail.

CONCLUSIONS

This study demonstrates that the proximal tendon of the semimembranosus muscle exhibits distinct anatomical variability. These findings may provide valuable reference data for clinicians, particularly orthopedic surgeons and radiologists, in the diagnosis and treatment of hamstring injuries.