Superficial back - muscle origin, insertion, action, nerve
Types of scapular movement
- elevation and depression - protraction and retraction - superior rotation and inferior rotation
Deep back muscles (embryology)
- epaxial muscle mass - dorsal rami - move trunk and head
Superficial back muscles (embryology)
- hypaxial muscle mass - ventral rami - move upper extremity
Innervation of Trapezius
Accessory nerve (CN XI)
Costovertebral joints
Between the head or a rib and costal hemifacets of thoracic vertebrae; considered synovial joints
Costotransverse joints
Between the tubercle of a rib and transverse process of thoracic vertebrae; considered synovial joints
Origin of Levator Scapulae
C1-C4 transverse processes
Innervation of Levator Scapulae
C3-C4 ventral rami and dorsal scapular nerve
Origin of Rhomboid Minor
C7-T1 spinous processes
Origin of Serratus Posterior Superior
C7-T3 spinous processes
Secondary (acquired) curvatures
Cervical and lumbar
Innervation of Rhomboid Major
Dorsal scapular nerve
Innervation of Rhomboid Minor
Dorsal scapular nerve
Action of Levator Scapulae
Elevates, protracts pectoral girdle, inferiorly rotates scapula
Action of Latissimus Dorsi
Extends, adducts, and medially rotates humerus
Facets of thoracic vertebrae
Face anteriorly and posteriorly (allows rotation)
Facets of lumbar vertebrae
Face medically and laterally (allowing for flexion, extension and lateral flexion)
Facets of cervical vertebrae
Face superiorly and inferiorly (allowing for all movements)
Movement of thoracic vertebrae
Facets allow for rotation however lateral flexion is severely limited due to attachment to the rubs and flexion is almost non-existent
Movement of lumbar vertebrae
Facets allows for extension and lateral flexion (most marked) and flexion; rotation is prevented
Movement of cervical vertebrae
Flexion and lateral side bending
Insertion of Latissimus Dorsi
Floor intertubercular groove
Insertion of Serratus Posterior Inferior
Inferior borders of ribs 9-12
Ligamentum flavum
Located between laminae of adjacent vertebrae, highly elastic and yellowish, helps maintain upright posture; contribute to the posterior boundaries of intervertebral foramina
Insertion of Rhomboid Major
Medial border of scapula
Insertion of Rhomboid Minor
Medial border of scapula, superior to rhomboid major
Origin of Trapezius
Medial third superior nuchal line, EOP, ligamentum nuchae, and T1-T12 spinous processes (midline)
Action of Rhomboid Minor
Retracfts, elevates pectoral girdle, inferiorly rotates scapula
Action of Rhomboid Major
Retracts, elevates pectoral girdle, inferiorly rotates scapula
Insertion of Trapezius
Spine of scapula, acromion, lateral third of clavicle
Insertion of Levator Scapulae
Superior angle of scapula
Insertion of Serratus Posterior Superior
Superior borders of ribs 2-5
Origin of Serratus Posterior Inferior
T11-L3 spinous processes
Origin of Rhomboid Major
T2-T5 spinous process
Origin of Latissimus Dorsi
T7-L5 spinous processes, thoracolumbar fascia, dorsal sacrum, and iliac crest
Primary curvatures
Thoracic and sacrococcygeal
Innervation of Latissimus Dorsi
Thoracodorsal nerve
Action of Trapezius
Upper trapezius elevates scapula, middle trapezius retracts scapula, and lower trapezius depresses scapular and lowers shoulder (superiorly rotates scapula)
Innervation of Serratus Posterior Inferior
Ventral rami
Innervation of Serratus Posterior Superior
Ventral rami
Action of Serratus Posterior Inferior
Weakly depresses ribs 9-12
Action of Serratus Posterior Superior
Weakly elevates ribs 2-5
