Sternocleidomastoid muscle
Start: upper margin of anterior part of manubrium sterni, upper surface of extremitas sternalis claviculae.
Tendril: processus mastoideus, lateral part of linea nuchalis superior.
Innervation: n. accessorius and fibres from C2-C4.
Function:
- Bowing of the head to the same side and rotation to the opposite (unilateral contraction);
- forward movement and forward tilt of the head (bilateral contraction);
- posterior bundles of head flexion.
Wedge: when m. sternocleidomastoideus is shortened, there is a striking tilt of the head to the ipsilateral side of the affected muscle and rotation to the opposite side. The condition is called torticollis.
Used literature
ČIHÁK, Radomír. Anatomy 1. 2. edition. Grada, 2001. 497 pp. ISBN 80-7169-970-5.
