Cervical spine and shoulder

What is the only movement at the AO joint

Flexion and extension

Trapezius

O: Occipital bone, ligamentum nuchae, spinous processes C7–T12.

I: Lateral third of clavicle, acromion, and spine of scapula.

A: Elevates, retracts, depresses, and upwardly rotates scapula.

Levator Scapulae

O: Transverse processes C1–C4.

I: Superior medial border of scapula.

A: Elevates and downwardly rotates scapula; assists cervical lateral flexion.

Rhomboid Major

O: Spinous processes T2–T5.

I: Medial border of scapula from spine to inferior angle.

A: Retracts and downwardly rotates scapula.

Rhomboid Minor

O: Spinous processes C7–T1.

I: Medial end of scapular spine.

A: Retracts and downwardly rotates scapula.

Serratus Anterior

O: External surfaces of ribs 1–8 or 1–9.

I: Anterior surface of medial border of scapula.

A: Protracts and upwardly rotates scapula; stabilizes scapula against thorax.

Pectoralis Minor

O: Ribs 3–5.

I: Coracoid process of scapula.

A: Protracts and depresses scapula; assists forced inspiration.

Subclavius

O: First rib and its costal cartilage.

I: Inferior surface of middle third of clavicle.

A: Depresses and stabilizes clavicle.

Pectoralis Major

O: Medial clavicle, sternum, costal cartilages of upper ribs, and external oblique aponeurosis.

I: Lateral lip of intertubercular groove of humerus.

A: Flexes, adducts, and medially rotates shoulder.

Latissimus Dorsi

O: Spinous processes T7–T12, thoracolumbar fascia, iliac crest, and lower ribs.

I: Floor of intertubercular groove of humerus.

A: Extends, adducts, and medially rotates shoulder.

Deltoid

O: Lateral third of clavicle, acromion, and spine of scapula.

I: Deltoid tuberosity of humerus.

A: Middle fibers abduct; anterior fibers flex and medially rotate; posterior fibers extend and laterally rotate shoulder.

Supraspinatus

O: Supraspinous fossa of scapula.

I: Superior facet of greater tubercle of humerus.

A: Initiates shoulder abduction and stabilizes glenohumeral joint.

Infraspinatus

O: Infraspinous fossa of scapula.

I: Middle facet of greater tubercle of humerus.

A: Laterally rotates shoulder and stabilizes glenohumeral joint.

Teres Minor

O: Middle portion of lateral border of scapula.

I: Inferior facet of greater tubercle of humerus.

A: Laterally rotates and weakly adducts shoulder; stabilizes glenohumeral joint.

Subscapularis

O: Subscapular fossa of scapula.

I: Lesser tubercle of humerus.

A: Medially rotates and adducts shoulder; stabilizes glenohumeral joint.

Teres Major

O: Posterior surface of inferior angle of scapula.

I: Medial lip of intertubercular groove of humerus.

A: Extends, adducts, and medially rotates shoulder.

Coracobrachialis

O: Coracoid process of scapula.

I: Middle third of medial humerus.

A: Flexes and adducts shoulder.

Biceps Brachii (Long Head)

O: Supraglenoid tubercle of scapula.

I: Radial tuberosity and bicipital aponeurosis.

A: Assists shoulder flexion and stabilizes shoulder; also flexes elbow and supinates forearm.

Triceps Brachii (Long Head)

O: Infraglenoid tubercle of scapula.

I: Olecranon process of ulna.

A: Extends shoulder and elbow; assists shoulder adduction.

Sternocleidomastoid

O: Manubrium of sternum and medial third of clavicle. I: Mastoid process and lateral superior nuchal line. A: Bilaterally flexes neck; unilaterally laterally flexes to same side and rotates head to opposite side.

Scalenus Anterior

O: Anterior tubercles of transverse processes C3–C6. I: Scalene tubercle of first rib. A: Flexes and laterally flexes neck; assists inspiration.

Scalenus Medius

O: Posterior tubercles of transverse processes C2–C7. I: Superior surface of first rib. A: Laterally flexes neck; assists inspiration.

Scalenus Posterior

O: Posterior tubercles of transverse processes C4–C6. I: External surface of second rib. A: Laterally flexes neck; assists inspiration.

Splenius Capitis

O: Lower half of ligamentum nuchae and spinous processes C7–T3/T4. I: Mastoid process and lateral superior nuchal line. A: Bilaterally extends head and neck; unilaterally rotates and laterally flexes to same side.

Splenius Cervicis

O: Spinous processes T3–T6. I: Transverse processes C1–C3/C4. A: Bilaterally extends neck; unilaterally rotates and laterally flexes to same side.

Longissimus Capitis

O: Transverse processes T1–T5 and articular processes C4–C7. I: Mastoid process. A: Extends and laterally flexes head; rotates head to same side.

Longissimus Cervicis

O: Transverse processes T1–T5. I: Posterior tubercles of transverse processes C2–C6. A: Extends and laterally flexes cervical spine.

Semispinalis Capitis

O: Transverse processes T1–T6 and articular processes C4–C7. I: Occipital bone between superior and inferior nuchal lines. A: Extends head and neck; rotates head to opposite side.

Semispinalis Cervicis

O: Transverse processes T1–T6. I: Spinous processes C2–C5. A: Extends cervical spine and rotates it to opposite side.

Spinalis Cervicis

O: Spinous processes C7–T2. I: Spinous processes C2–C4. A: Extends cervical spine.

Longus Capitis

O: Anterior tubercles of transverse processes C3–C6. I: Basilar portion of occipital bone. A: Flexes head and cervical spine.

Longus Colli

O: Bodies of T1–T3 and C5–C7; transverse processes C3–C5. I: Anterior tubercle of C1 and bodies of C2–C4. A: Flexes and stabilizes cervical spine; assists slight contralateral rotation.

Rectus Capitis Anterior

O: Lateral mass and anterior surface of transverse process of C1. I: Basilar portion of occipital bone. A: Flexes head at atlanto-occipital joint.

Rectus Capitis Lateralis

O: Transverse process of C1. I: Jugular process of occipital bone. A: Laterally flexes and stabilizes head.

Rectus Capitis Posterior Major

O: Spinous process of C2. I: Lateral part of inferior nuchal line. A: Extends head and rotates it to same side.

Rectus Capitis Posterior Minor

O: Posterior tubercle of C1. I: Medial part of inferior nuchal line. A: Extends and stabilizes head.

Obliquus Capitis Superior

O: Transverse process of C1. I: Occipital bone between superior and inferior nuchal lines. A: Extends and laterally flexes head.

Obliquus Capitis Inferior

O: Spinous process of C2. I: Transverse process of C1. A: Rotates head to same side.

Multifidus (Cervical)

O: Articular processes C4–C7. I: Spinous processes 2–4 vertebral levels above origin. A: Stabilizes cervical spine; assists extension and contralateral rotation.

Rotatores (Cervical)

O: Transverse processes of cervical vertebrae. I: Lamina and spinous processes of vertebrae one or two levels above. A: Stabilize vertebrae; assist extension and contralateral rotation.

Interspinales (Cervical)

O: Spinous processes of cervical vertebrae. I: Spinous processes of adjacent vertebrae. A: Assist cervical extension and stabilization.

Intertransversarii (Cervical)

O: Transverse processes of cervical vertebrae. I: Transverse processes of adjacent vertebrae. A: Laterally flex and stabilize cervical spine.