Anatomy study note · Head and neck

Sternocleidomastoid

The oblique muscle crossing the side of the neck from the sternoclavicular joint to the mastoid process, dividing the neck into anterior and posterior triangles.

Key points

• Sternum + clavicle → mastoid.
• Accessory nerve (XI).
• One side: turns the face to the opposite side.
• Boundary between anterior and posterior triangles.
• Striated muscle: myotomes + local mesenchyme.
• Nerve supply indicates origin.
• Skeletal muscle: multinucleated, peripheral nuclei, striated.
• Epimysium → perimysium → endomysium.

The full note in the atlas also covers

Relations · Origin · Insertion · Action · Nerve supply · Histology · Development · Clinical notes

Sign in free to see it on the 3D model, read the full note and practise questions on it.

Written from

• Snell’s Clinical Anatomy by Regions, 10th ed., ch. 12, PDF pp. 1616–1617, 1624–1626
• Inderbir Singh’s Human Embryology, ch. 7, PDF pp. 92, 108–109; ch. 10, PDF p. 138
• BRS Cell Biology & Histology, 7th ed., ch. 8, PDF pp. 135–144

More from the head and neck

• Sternohyoid
• Sternothyroid
• Stylohyoid
• Stylopharyngeus
• Subclavian artery
• Subclavian vein
• Sublingual gland
• Submandibular gland
• Superficial and regional cervical lymph nodes
• Superior oblique
• Superior rectus
• Superior temporal gyrus

Privacy policy · Designed by DATXOC LLC.