Muscle Name: semitendonosus

AKA:  musculus semitendinosus

Abbreviation: ST

Spinal Nerve Roots:
    L4
    L5
    S1
Plexus:
    lumbosacral plexus

Named Nerves:
    sciatic nerve (tibial division)

Proximal Attachment:  ischial tuberosity

Distal Attachment:  Medail surface of the proximal tibia

Action: Extension of the thigh, Flexion of the knee, Internal rotation when the knee is bent.

Needle Insertion: Approximately midway midway between the medial epicondyle and the ischial tuberosity.

Activation for EMG:   Have the patient flex the knee

Pitfalls:  If the needle is too laeral the biceps femoris will be sampled. Too medial and the semitendinosus will be sampled.

Notes: