Sternocleidomastoid

Other Names

• Sterno-mastoid
• Neck (Front / Sides)
• Neck Flexors

Heads

1. Anterior Fibers
2. Posterior Fibers

Movement

Neck (Atlantooccipital & Atlantoaxial)

• Flexion [1]
  • Both Sides
• Rotation [1, 2]
  • Rotation right [Left Sternocleidomastoid]
  • Rotation left [Right Sternocleidomastoid]
• Lateral Flexion [1, 2]
  • Lateral flexion right [Right Sternocleidomastoid]
  • Lateral flexion left [Left Sternocleidomastoid]
• Extension [2]

Spine (Cervical)

• Flexion [1, 2]
  • Both Sides
• Rotation [1, 2]
  • Rotation right [Left Sternocleidomastoid]
  • Rotation left [Right Sternocleidomastoid]
• Lateral Flexion [1, 2]
  • Lateral flexion right [Right Sternocleidomastoid]
  • Lateral flexion left [Left Sternocleidomastoid]

Attachments

Origin

• Sternum [1]
  • Manubrium
• Clavicle (Medial) [2]

Insertion

• Skull [1, 2]
  • Mastoid Process

Related Muscles

• Splenius