Intrinsic Muscles Flashcards
What is the insertion of the multifidus?
Obliquely to entire length of spinous processes of vertebrae 2-4 segments superior to origin. Thickest in lumbar
What is the origin of the multifidus?
Posterior sacrum, post. sup iliac spine of ilium, aponeurosis of erector spinae, sacroiliac ligaments, mamillary processes of lumbar, transverse processes of thoracic, articular processes C4-C7
What innervates the multifidus?
Posterior ramus of spinal nerves
What are the actions of multifidus?
Unilateral contraction rotates to contralateral side; stabilizes vertebrae during local movements of vertebral column
What is the origin of rotatores?
Transverse processes of vertebrae
What is the insertion of rotatores?
Superomedially to attach to junction of lamina and transverse process or spinous process of vertebra immediately (brevis) or two segments (longus) superior to vertebra of origin
What innervates the rotatores?
Posterior rami of spinal nerves
What are the actions of rotatores?
Organs of proprioception, stabilize vertebra and assist with local extension. Rotatory movements of vertebral column
What is the origin of semispinalis?
Transverse processes of C4-T10 vertebrae
What is the insertion of semispinalis?
Occipital bone and spinous processes in upper thoracic and cervical regions, 4-6 segments
What innervates semispinalis?
Posterior rami of spinal nerves
What are the actions of semispinalis?
Extend head and thoracic and cervical regions of vertebral column and rotates them contralaterally
Splenius
Origin
Spinous processes of C7-T6 vertebrae and nuchal ligament
Splenius
Insertion
Capitis-mastoid process of temporal bone and lateral third of superior nuchal line of occipital bone
Cervicis-tubercles of transverse processes of C1-C3 or C4 vertebrae
Splenius
Innervation
Posterior rami of spinal nerves
Splenius
Actions
Alone-laterally flex neck and rotate head to side of active muscles
Together-extend head and neck
Iliocostalis
origin
Posterior surface of sacrum, sacroiliac ligaments, supraspinous ligament, posterior part of iliac crest, spinous processes of inferior lumbar and sacral
Iliocostalis
Insertion
Angles of lower ribs and cervical transverse processes
Iliocostalis
Innervation
Posterior rami of spinal nerves
Iliocostalis
Actions
Unilaterally-laterally flex vertebral column
Bilaterally-extend vertebral column and head
Longissimus
Origin
Posterior surface of sacrum, posterior part of iliac crest, sacroiliac ligaments, supraspinous ligament, spinous processes of inferior lumbar and sacral
Longissimus
Insertion
between tubercles and angles to transverse processes in cervical and thoracic, mastoid process of temporal bone
Longissimus
Innervation
Posterior rami of spinal nerves
Longissimus
Actions
Unilaterally-laterally flex vertebral column
Bilaterally-extend vertebral column and head
Spinalis
Origin
Posterior surface of sacrum, posterior part of iliac crest, sacroiliac ligaments, supraspinous ligament, spinous processes of inferior lumbar and sacral
Spinalis
Insertion
Spinous processes in upper thoracic region to cranium
Spinalis
Innervation
Posterior rami of spinal nerves
Spinalis
Actions
Unilaterally-laterally flex vertebral column
Bilaterally-extend head and vertebral column
