Semitendinosus

Authors

Affiliations

Nathaniel Yomogida, B.S., SPT

Doctor of Physical Therapy

B.S. in Kinesiology

Chloë Kerstein, B.S., SPT

Doctor of Physical Therapy

B.A. in Neuroscience

Overview

Muscle	Origin	Insertion	Innervation	Action
Semitendinosus	Ischial tuberosity Sacrotuberous lig. (common head with biceps femoris long head)	Pes anserine	Tibial n. L5 - S2	Hip: Extension Knee: Flexion, IR Pelvis: Sagittal stabilization

Origin

• Ischial tuberosity¹
• Sacrotuberous lig.¹
• (common head with long head of biceps femoris)¹

Insertion

• Medial to the tibial tuberosity in the Pes Anserine¹
  • (along with the tendons of gracilis and sartorius)¹

Nerve

Tibial N. (division of Sciatic N.) (L5, S1, S2)¹

Action

• Hip: Extension¹
• Pelvic Stabilization: Sagittal plane¹
• Knee: Flexion and Internal rotation¹

Overview

“The semitendinosus muscle (see Fig. 19-8) arises from the upper portion of the ischial tuberosity via a shared tendon with the long head of the biceps femoris. From there, it travels distally, becoming cord-like about two-thirds of the way down the posteromedial thigh. Passing over the MCL, it inserts into the medial surface of the tibia and deep fascia of the lower leg, distal to the gracilis attachment, and posterior to the sartorius attachment. These three structures are collectively called the pes anserinus (“goose foot”) at this point. Like the semimembranosus, the semitendinosus functions to extend the hip, flex the knee, and internally rotate the tibia.”²

References

1.

Gilroy AM, MacPherson BR, Wikenheiser JC, Voll MM, Wesker K, Schünke M, eds. Atlas of Anatomy. 4th ed. Thieme; 2020.

2.

Dutton M. Dutton’s Orthopaedic Examination, Evaluation, and Intervention. 5th ed. McGraw Hill Education; 2020.