Movement of Head and Neck Muscles
Obliquus capitis superior
Action: Rotates head to same side O: Transverse processes of atlas I: Inferior nuchal line of occipital bone Picture: D
Scalene muscle
Anterior, middle, and posterior Action: Flexes neck and elevate 1st and 2nd ribs during inspiration (breathing in) O: Transverse process of cervical vertebrae I: Superior surface of 1st and 2nd ribs
Posterior neck muscle
Muscles responsible for mainly rotating the head Picture: Splenius capitis and splenius cervicis is not shown
Splenius cervicis
Unilateral action: Rotation of head to same side Bilateral action: Extends head/neck O: Ligamentum nuchae (septum that extends from occipital protuberance to spine of C7) I: Occipital bone/mastoid process of temporal bone
Rectus Capitis Posterior Minor
Action: Extends head/neck O: Posterior tubercle of atlas I: Inferior nuchal line of occipital bone Picture: B
Rectus Capitis Posterior Major
Action: Extends head/neck O: Spinous process of axis I: Inferior nuchal line of occipital bone Picture: A
Obliquus capitis inferior
Action: Rotates head to same side O: Spinous process of axis I: Transverse process of atlas Picture: C
Anterolateral neck muscle
Head movement is controlled by both head and neck muscles O: Vertebral column, thoracic cage, and pectoral girdle I: Cranial bones These muscles can have more than 1 action: Unilateral - one muscles (left or right) is contracting Bilateral - both the left and right muscles are contracting Picture: cannot see posterior scalene muscle, next to the other scalene muscles but can only be seen posteriorly
Sternocleidomastoid
Unilateral action: Rotation of head to opposite side - if right side of this muscle contracts, head turns to the left side Bilateral action: Flexes neck O: Manubrium and sternal end of clavicle I: Mastoid process
Longissimus capitis
Unilateral action: Rotation of head to same side Bilateral action: Extends head/neck O: Transverse process of T1-T4 and articular processes of C4-C7 I: Mastoid process
Splenius capitis
Unilateral action: Rotation of head to same side Bilateral action: Extends head/neck O: Ligamentum nuchae (septum that extends from occipital protuberance to spine of C7) I: Occipital bone/mastoid process of temporal bone