Back, Chest, and Shoulder Muscles Flashcards
SUPERFICIAL ERECTOR SPINAE
The superficial erector spinae are a complex muscle group made up of the iliocostalis, longissimus, and spinalis muscles, each of which are subdivided based on the vertebrae at which they insert, respectively. All muscles of the superficial erector spinae share a common origin of the iliac crest of the pelvis, sacrum, and spinous and transverse processes of T1–L5.
ILIOCOSTALIS: LUMBORUM DIVISION
ORIGIN
Common origin
INSERTION
Inferior border of ribs 7–12
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of thoracic and lumbar nerves
ILIOCOSTALIS: THORACIS DIVISION
ORIGIN
Common origin
INSERTION
Superior border of ribs 1–6
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of thoracic nerves
ILIOCOSTALIS: CERVICUS DIVISION
ORIGIN
Common origin
INSERTION
Transverse processes of C4–C6
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of thoracic nerves
LONGISSIMUS: THORACIS DIVISION
ORIGIN
Common origin
INSERTION
Transverse processes of T1–T12 and ribs 2–12
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of thoracic and lumbar nerves
LONGISSIMUS: CERVICUS DIVISION
ORIGIN
Common origin
INSERTION
Transverse processes of C6–C2
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of cervical nerves
LONGISSIMUS: CAPITIS DIVISION
ORIGIN
Common origin
INSERTION
Mastoid process of the skull
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of cervical nerves
SPINALIS: THORACIS DIVISION
ORIGIN
Common origin
INSERTION
Spinous processes of T7–T4
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of thoracic nerves
SPINALIS: CERVICUS DIVISION
ORIGIN
Common origin
INSERTION
Spinous processes of C3–C2
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of cervical nerves
SPINALIS: CAPITIS DIVISION
ORIGIN
Common origin
INSERTION
Between the superior and inferior nuchal lines on occipital bone of the skull
ISOLATED FUNCTION
Concentric Action
Spinal extension, rotation, and lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion, rotation, and lateral flexion
Isometric Action
Stabilizes the spine during functional movements
INNERVATION
Dorsal rami of cervical nerves
QUADRATUS LUMBORUM
ORIGIN
Iliac crest of the pelvis
INSERTION
12th rib and transverse processes L2–L5
ISOLATED FUNCTION
Concentric Action
Spinal lateral flexion
INTEGRATED FUNCTION
Eccentric Action
Decelerates contralateral lateral spinal flexion
Isometric Action
Stabilizes the lumbo-pelvic-hip complex
INNERVATION
Spinal nerves (T12–L3)
TRANSVERSOSPINALIS: THORACIS DIVISION
ORIGIN
Transverse processes of T12–T7
INSERTION
Spinous processes of T4–C6
ISOLATED FUNCTION
Concentric Action
Produces spinal extension and lateral flexion; extension and contralateral rotation of the head
INTEGRATED FUNCTION
Eccentric Action
Decelerates lateral flexion of the spine, flexion, and contralateral rotation of the head
Isometric Action
Stabilizes the spine
INNERVATION
Dorsal rami C1–T6 spinal nerves
TRANSVERSOSPINALIS: CERVICUS DIVISION
ORIGIN
Transverse processes of T6–C4
INSERTION
Spinous processes of C5–C2
ISOLATED FUNCTION
Concentric Action
Produces spinal extension and lateral flexion and extension and contralateral rotation of the head
INTEGRATED FUNCTION
Eccentric Action
Decelerates lateral flexion of the spine, and flexion and contralateral rotation of the head
Isometric Action
Stabilizes the spine
INNERVATION
Dorsal rami C1–T6 spinal nerves
TRANSVERSOSPINALIS: CAPITUS DIVISION
ORIGIN
Transverse processes of T6–C7 Articular processes of C6–C4
INSERTION
Nuchal line of occipital bone of the skull
ISOLATED FUNCTION
Concentric Action
Produces spinal extension and lateral flexion and extension and contralateral rotation of the head
INTEGRATED FUNCTION
Eccentric Action
Decelerates lateral flexion of the spine, and flexion and contralateral rotation of the head
Isometric Action
Stabilizes the spine
INNERVATION
Dorsal rami C1–T6 spinal nerves
MULTIFIDUS
ORIGIN
Posterior aspect of the sacrum and processes of the lumbar, thoracic, and cervical spine
INSERTION
Spinous processes 1 to 4 segments above the origin
ISOLATED FUNCTION
Concentric Action
Spinal extension and contralateral rotation
INTEGRATED FUNCTION
Eccentric Action
Spinal flexion and rotation
Isometric Action
Stabilizes the spine
INNERVATION
Corresponding spinal nerves
LATISSIMUS DORSI
ORIGIN
Spinous processes of T7–T12, iliac crest of the pelvis, thoracolumbar fascia, and ribs 9–12
INSERTION
Inferior angle of the scapula and intertubercular groove of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder extension, adduction, and internal rotation
INTEGRATED FUNCTION
Eccentric Action
Shoulder flexion, abduction, external rotation, and spinal flexion
Isometric Action
Stabilizes the lumbo-pelvic-hip complex and shoulder
INNERVATION
Thoracodorsal nerve (C6–C8)
SERRATUS ANTERIOR
ORIGIN
Ribs 4–12
INSERTION
Medial border of the scapula
ISOLATED FUNCTION
Concentric Action
Scapular protraction
INTEGRATED FUNCTION
Eccentric Action
Scapular retraction
Isometric Action
Stabilizes the scapula
INNERVATION
Long thoracic nerve (C5–C7)
RHOMBOIDS
ORIGIN
Spinous processes of C7–T5
INSERTION
Medial border of the scapula
ISOLATED FUNCTION
Concentric Action
Produces scapular retraction and downward rotation
INTEGRATED FUNCTION
Eccentric Action
Scapular protraction and upward rotation
Isometric Action
Stabilizes the scapula
INNERVATION
Dorsal scapular nerve (C4–C5)
LOWER TRAPEZIUS
ORIGIN
Spinous processes of T6–T12
INSERTION
Spine of the scapula
ISOLATED FUNCTION
Concentric Action
Scapular depression
INTEGRATED FUNCTION
Eccentric Action
Scapular elevation
Isometric Action
Stabilizes the scapula
INNERVATION
Cranial nerve XI and ventral rami C2–C4
MIDDLE TRAPEZIUS
ORIGIN
Spinous processes of T1–T5
INSERTION
Acromion process of the scapula and superior aspect of the spine of the scapula
ISOLATED FUNCTION
Concentric Action
Scapular retraction
INTEGRATED FUNCTION
Eccentric Action
Scapular protraction and elevation
Isometric Action
Stabilizes scapula
INNERVATION
Cranial nerve XI and ventral rami C2–C4
UPPER TRAPEZIUS
ORIGIN
External occipital protuberance of the skull and spinous process of C7
INSERTION
Lateral third of the clavicle and acromion process of the scapula
ISOLATED FUNCTION
Concentric Action
Cervical extension, lateral flexion, and rotation and scapular elevation
INTEGRATED FUNCTION
Eccentric Action
Cervical flexion, lateral flexion, rotation, and scapular depression
Isometric Action
Stabilizes the cervical spine and scapula and stabilizes the medial border of the scapula creating a stable base for the prime movers during scapular abduction and upward rotation
INNERVATION
Cranial nerve XI and ventral rami C2–C4
LEVATOR SCAPULAE
ORIGIN
Transverse processes of C1–C4
INSERTION
Superior vertebral border of the scapula
ISOLATED FUNCTION
Concentric Action
Cervical extension, lateral flexion, and ipsilateral rotation when the scapula is anchored and assists in elevation and downward rotation of the scapula
INTEGRATED FUNCTION
Eccentric Action
Cervical flexion, contralateral cervical rotation, lateral flexion, scapular depression, and upward rotation when the neck is stabilized
Isometric Action
Stabilizes the cervical spine and scapula
INNERVATION
Ventral rami C3–C4 and dorsal scapular nerve
PECTORALIS MAJOR
ORIGIN
Anterior surface of the clavicle, anterior surface of the sternum, and cartilage of ribs 1–7
INSERTION
Greater tubercle of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder flexion (clavicular fibers), horizontal adduction, and internal rotation
INTEGRATED FUNCTION
Eccentric Action
Shoulder extension, horizontal abduction, and external rotation
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Medial and lateral pectoral nerves (C5–C7)
PECTORALIS MINOR
ORIGIN
Ribs 3–5
INSERTION
Coracoid process of the scapula
ISOLATED FUNCTION
Concentric Action
Protracts the scapula
INTEGRATED FUNCTION
Eccentric Action
Scapular retraction
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Medial pectoral nerve (C6–T1)
ANTERIOR DELTOID
ORIGIN
Lateral third of the clavicle
INSERTION
Deltoid tuberosity of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder flexion and internal rotation
INTEGRATED FUNCTION
Eccentric Action
Shoulder extension and external rotation
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Axillary nerve (C5–C6)
MEDIAL DELTOID
ORIGIN
Acromion process of the scapula
INSERTION
Deltoid tuberosity of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder abduction
INTEGRATED FUNCTION
Eccentric Action
Shoulder adduction
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Axillary nerve (C5–C6)
POSTERIOR DELTOID
ORIGIN
Spine of the scapula
INSERTION
Deltoid tuberosity of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder extension and external rotation
INTEGRATED FUNCTION
Eccentric Action
Shoulder flexion and internal rotation
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Axillary nerve (C5–C6)
TERES MINOR
ORIGIN
Lateral border of the scapula
INSERTION
Greater tubercle of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder external rotation
INTEGRATED FUNCTION
Eccentric Action
Shoulder internal rotation
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Axillary nerve (C5–C6)
INFRASPINATUS
ORIGIN
Infraspinous fossa of the scapula
INSERTION
Middle facet of the greater tubercle of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder external rotation
INTEGRATED FUNCTION
Eccentric Action
Shoulder internal rotation
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Suprascapular nerve (C5–C6)
SUBSCAPULARIS
ORIGIN
Subscapular fossa of the scapula
INSERTION
Lesser tubercle of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder internal rotation
INTEGRATED FUNCTION
Eccentric Action
Shoulder external rotation
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Upper and lower subscapular nerves (C5–C6)
SUPRASPINATUS
ORIGIN
Supraspinous fossa of the scapula
INSERTION
Superior facet of the greater tubercle of the humerus
ISOLATED FUNCTION
Concentric Action
Abduction of the arm
INTEGRATED FUNCTION
Eccentric Action
Adduction of the arm
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Suprascapular nerve (C5–C6)
TERES MAJOR
ORIGIN
Inferior angle of the scapula
INSERTION
Lesser tubercle of the humerus
ISOLATED FUNCTION
Concentric Action
Shoulder internal rotation, adduction, and extension
INTEGRATED FUNCTION
Eccentric Action
Shoulder external rotation, abduction, and flexion
Isometric Action
Stabilizes the shoulder girdle
INNERVATION
Lower subscapular nerve
