Intrinsic Back Muscles Flashcards
Splenius Capitis
Proximal: nuchal ligament & spinous process (C7-T3)
Distal: superior nuchal line & mastoid process
Innervation: dorsal rami of cervical spinal nerves (C2-C3)
Blood supply: occipital artery
Functions: neck/head EXT (B) & ipsilateral SB/RT
Splenius Cervicis
Proximal: spinous process T3-T6
Distal: transverse process C3-C6
Innervation: dorsal rami of spinal nerves
Blood supply: occipital artery & posterior intercostal artery
Functions: neck EXT (B) & ipsilateral SB/RT
Iliocostalis Cervicis (erector spinae)
Proximal: superior angle of ribs 3-6
Distal: posterior tubercle of transverse processes C4- C6
Innervation: dorsal rami of spinal nerves
Blood supply: posterior intercostal arteries
Function: back EXT (B) & ipsilateral back SB (L/R)
Iliocostalis Thoracis (erector spinae)
Proximal: superior angle of ribs 7-12 & medial tendon of lumborum
Distal: superior angle of ribs 1-6 & C7 transverse process
Innervation: dorsal rami of spinal nerves
Blood supply: subcostal arteries
Functions: back EXT (B), ipsilateral back SB (L/R)
Iliocostalis Lumborum (erector spinae)
Proximal: lateral erector spinae common tendon & iliac crest
Distal: inferior angle of ribs 6-7
Innervation: dorsal rami of spinal nerves
Blood supply: lumbar arteries
Functions: ipsilateral RT (L/R) & expiration
Longissimus Capitis (erector spinae)
Proximal: transverse processes of C4-T5
Distal: mastoid process
Innervation: dorsal rami of spinal nerves
Blood supply: posterior intercostal arteries
Functions: ipsilateral RT of head (L/R)
Longissimus Cervicis (erector spinae)
Proximal: transverse processes of T1-T5
Distal: posterior tubercle of transverse processes of C2-C6
Innervation: dorsal rami of spinal nerves
Blood supply: subcostal arteries
Functions: back EXT & back SB (L/R)
Longissimus Thoracis (erector spinae)
Proximal: erector spinae common tendon, thoracolumbar fascia, transverse & maxillary processes of lumbar vertebrae
Distal: transverse process of all thoracic vertebrae
Innervation: dorsal rami of spinal nerves
Blood supply: lumbar arteries
Functions: depress ribs for expiration
Spinalis Capitis (erector spinae)
Proximal: spinous process T1/C7
Distal: superior nuchal line with semispinalis
Innervation: dorsal rami of spinal nerves
Blood supply: posterior intercostal arteries
Functions: back EXT(B), ipsilateral back SB (L/R), & RT
Spinalis Cervicis ( erector spinae)
Proximal: spinous process from T1-T2
Distal: spinous process C1-C4
Innervation: dorsal rami of spinal nerves
Blood supply: subcostal arteries
Functions: back EXT (B), ipsilateral SB (L/R), & RT
Spinalis Thoracis (erector spinae)
Proximal: T11-L2 spinous process
Distal: spinous process of thoracic vertebrae
Innervation: dorsal rami of spinal nerves
Blood supply: lumbar arteries
Functions: back EXT, ipsilateral SB (L/R), & RT
Multifidi
Proximal: sacrum, PSIS, SI ligament, lumbar mamillary processes, & transverse processes of C4-T12
Distal: lateral aspects and tips of the spinous processes of vertebrae 2-5 levels above until C2
Innervation: dorsal rami of spinal nerves
Blood supply: varies at diff levels
Functions: back EXT (B), ipsilateral SB (L/R), & contralateral RT (L/R)
Semispinalis Capitis
Proximal: transverse process of C7-T7 & articular processes of C4-C6
Distal: btwn superior/inferior nuchal line & deep to trapezius attatchment
Innervation: dorsal rami of spinal nerves
Blood supply: various arteries at diff levels
Functions: head EXT, ipsilateral SB (L/R), & contralateral RT (L/R)
Semispinalis Cervicis
Proximal: transverse processes of T1-T6
Distal: spinal processes of C2-C5
Innervation: dorsal rami of spinal nerves
Blood supply: varies at diff levels
Functions: back EXT (B), ipsilateral SB (L/R), & contralateral RT (L/R)
Semispinalis Thoracis
Proximal: transverse process of T6-T10
Distal: spinous processes of T4-T6
Innervation: dorsal rami of spinal nerves
Blood supply: varies at diff levels
Functions: back EXT (B), ipsilateral SB (L/R), & contralateral RT (L/R)
