Spinal Muscles (Origin, Insertion, Function)
Rectus abdominis
Crest of pubis and pubic symphysis TO cartilage of 5-7th ribs and xiphoid process. *Compresses abdominal cavity and flexes vertebral column.
External oblique
Lower 8 ribs TO Iliac crest and linea alba *compresses abdominal cavity and laterally flexes and rotates vertebral column.*
External Intercostals
Lower margin of upper 11 ribs TO Superior border of *rib below* (these do not go on costal cartilage) *pull ribs toward one another to ELEVATE rib cage*
Middle scalene
Upper surface of 1st rib to transverse process of *C2-C7*. *above will raise 1st rib, below will laterally flex neck*
Anterior Scalene
Upper surface of 1st rib to transverse processes of *C3-C6*. *bends cervical portion of vertebral column forward and laterally*
Subcostals
angle of rib (halfway) TO inner surface of 2nd or 3rd rib below. *draws ventral ribs downward* (Deep and synergistic to intercostals)
Internal oblique
Anterior 2/3 of Iliac crest TO last 3 ribs. *compresses abdominal contents, laterally bends and rotates vertebral column, helps flex vertebral column.
Transverse abdominus
Iliac crest and cartilage of lower 6 ribs to linea alba. *constricts abdomen and supports viscera.
Transverse thoracis
Inner surface of body of sternum to inner surface of costal cartilages of 2-6th ribs. *draws ventral part of rib downward)
Internal Intercostals
Inner surface of rib and costal cartilage to rib below. *draws ribs together and depress rib cage.* (difference between external and internal is that external does not go all the way medial like internal)
Diaphragm
L1-3, lower 6 costal cartilages and xiphoid process TO form central tendon. *flattens on contraction, increasing vertical dimensions of thorax*
Longus colli (Spinal flexor)
Origin: Anterior surfaces of cervical/thoracic Insertion: Transverse processes Action: Flexes/rotates
Longissimus thoracis (Intermediate)
Origin: Broad aponeurosis joining iliocostalis Insertion: Superior thoracic/lumbar transverse processes and inferior surfaces of lower 10 ribs Action: Extension; ipsilateral flexion
Longus capitis (Spinal flexor)
Origin: C4-6 transverse processes Insertion: Occipital bone Action: Flexion; ipsilateral rotation
Semispinalis cervicis (Deep)
Origin: C4-T6 transverse processes Insertion: C2-5 spinous processes Action: Extend and contra laterally rotate
Semispinalis capitis (Deep)
Origin: C4-T7 transverse processes Insertion: Nuchal line of Occipital bone Action: Extend; contralateral rotation
Spinalis cervicis (Intermediate)
Origin: C7 spinous process Insertion: C1, 3-4 spinous process Action: Extension
Quadratus lumborum (Spinal flexor)
Origin: Iliac crest Insertion: Last rib/transverse processes of L1-L4 Action: Depress ribs; lateral flexion
Iliocostalis lumborum (Intermediate)
Origin: Iliac, sacral crests; lumbar spinous processes Insertion: Inferior surface of ribs 6-12 Action: Extends vertebra; depresses ribs
Multifudus (Deep)
Origin: Sacrum, PSIS and transverse processes Insertion: *Spinous* processes of *superior* vertebrae Action: Extend and contra laterally rotate
Splenius capitis (Superficial)
Origin: Spinous process of C7-T4 TO Mastoid. *Extend neck; ipsilaterally rotate/laterally flexes head*
Interspinales (Deep)
Origin: Spinous processes Insertion: Spinous processes of next superior vertebra *gaps between C7-T1, T12-L1* Action: Extension
Iliocostalis thoracis (Intermediate)
Origin: Superior border of 6-12 ribs Insertion: Superior ribs and C7 transverse process Action: Stabilize thorax in extension
Iliocostalis cervicis (Intermediate)
Origin: Superior border of vertebrosternal ribs Insertion: C4-6 transverse processes Action: Extends vertebra; depresses ribs
Longissimus cervicis (Intermediate)
Origin: Superior thoracic vertebrae transverse process Insertion: Middle/superior cervical transverse process Action: Extend; ipsilateral rotation, flexion
Spinal thoracis (Intermediate)
Origin: T11-L2 spinous process Insertion: superior thoracic spinous processes Action: Extends
Semispinalis thoracis (Deep)
Origin: T7-T12 transverse processes Insertion: C6-T4 spinous processes Action: Extend and contra laterally rotate
Rotatores (Deep)
Origin: Transverse processes Insertion: Spinous processes one above and 2 above. Action: Extend and contra laterally rotate
Intertransversarii (Deep)
Origin: Transverse processes Insertion: Transverse processes superiorly Action: Lateral flexion
Longissimus capitis (Intermediate)
Origin: inferior cervical/superior thoracic transverse process Insertion: Mastoid process Action: Extend; ipsilateral rotation, flexion
Posterior Scalene
Outer surface of *2nd* rib to posterior transverse process of *C4-C6*. *Raises 2nd rib or bends lower cervical portion to same side*
Rectus Capitus POsterior Minor
Post tubercle of C1 (has no spinous process) TO straight up to medial nuchal line. *extends the head*
Rectus Capitis posterior Major
Spinous C2 then sup lateral to nuchal line *extends and rotates head to same side*
Obliquus Capitis Inferior
Spinous process of C2 to transverse process of C1. *rotates head*
Serratus posterior Superior
Spinous process of C6-T3 TO upper border of ribs 2-5. *raises ribs during inspiration* (deep to rhomboids)
Spinalis Thoracic
Spinous process of T11-L2 TO T1-T8. *Extends vertebral column*
Serratus posterior inferior
Spinous process of T11-L3 TO inferior borders and outer surfaces of lower 4 ribs (by angle) *depressess last 4 ribs.
Splenius cervicis
Spinous process of* T3-T6* TO transverse process of *C1-C3* *Extend neck , ipsilateral lateral flex and rotation*
Longus Colli
Superior: transverse 3-5 to atlas Medial: one big long line from C3-T2 Inferior: side of medial colli T1-3 to Transverse C5-6 *Flex neck, laterally bends, rotates opposite side*
pSOAS minor
T12 and L1 to Superior ramus of pubis
Rectus Capitus Lateralis
Transverse C1 straight up to occipital bone. (muscle is just lateral to Rec. capit Anterior) *bends head laterally*
Rectus Capitus Anterior
Transverse C1 then superior medial to occipital bone. *flexes head*
Obliquus Capitis Superior
Transverse C1 to oblique medial. *bends head backward and laterally to same side*
Spinalis Capitis
Transverse process of C4-T7 TO superior and inferior nuch al lines. *extends vertebral column*
Levatores Costarum
Transverse process of c7-T11 TO costal angle of next lower rib. *raises rib and laterally flexes and rotates vertebral column.