Final: Lecture 14 Flashcards
Intrinsic muscles of the back…
- support upright posture and allow movements of the vertebral column
- involved in proprioception and are innervated by the dorsal rami of spinal nerves
Extrinsic muscles of the back…
- move the limbs
* Innervated by CN1 (accessory nerve) or branches of brachial plexus
Serratus posterior superior
- Proximal: nuchal ligament, spinous processes of C7-T3 vertebrae
- Distal: superior border of ribs 2-4
- Innervation: T2-T5 intercostal nerves (ventral rami)
Serratus Posterior Inferior
- PA: spinous processes of T11-L2
- DA: inferior borders of ribs 8-12, near their angles
- Actions: depress ribs
- Innervation: intercostal nerves and subcostal nerve (ventral rami)
Name the two extrinsic muscles of the back.
•serratus posterior superior and inferior
Splenius Cervicis
- Origin: nuchal ligament (ligamentum nuchae) and spinous processes of T1-T6
- Insertions: tubercles of transverse processes of C1-C4
- Actions: bilaterally- extend head and neck, Unilaterally-laterally flex neck and rotate head to side of contracting muscles
- Innervation: dorsal rami of spinal nerves
Splenius Capitis
- Origin: nuchal ligament and spinous processes of T1-T6
- Insertions: lateral parts of mastoid processes and superior nuchal line
- Actions: Bilaterally-extend head and neck, Unilaterally-laterally flex neck and rotate head to side of contracting muscle
- Innervation: dorsal rami of spinal nerves
Superficial layer of Erector spinae group
- Iliocostalis, longissimus, and spinalis
- Actions: bilaterally-extend vertebral column and head, Unilaterally-laterally flex vertebral column
- Innervation: dorsal rami of spinal nerves
Iliocostalis (most lateral portion)
- Lumborum, thoracis, and cervicis
- Orgin: broad common tendon attaches to iliac crest, posterior part of sacrum, sacroiliac ligaments, sacral and inferior lumbar spinous processes, and supraspinous ligament
Longissimus Thoracis
- Orgin: same as iliocostalis
* Insertion: ribs and adjacent transverse processes of thoracic vertebrae
Longissimus Cervicis
- Origin: transverse process of cervical vertebrae
* Insertion: transverse processes of cervical vertebrae
Longissimus Capitis
- Origin: transverse processes of cervical vertebrae
* Insertion: mastoid processes
Spinalis
- Thoracis: orgain on spinous processes and insert on spinous processes superior to them
- Cervicis and Capitis
Transversospinalis Group
- Semispinalis, Rotatores, Multifidus
- Posture muscles
- Innervation: dorsal rami of spinal nerves
Semispinalis Cervicis
- cervical transverse processes to spinous processes of 2nd cervical vertebra
- extend head, thoracic and cervical regions, rotates them contralaterally
Semispinalis Capitis
- superfical to cervicis
- transverse processes of 1-6 thoracic vertebrae to nuchal line
- extend head, thoracic, and cervical regions, rotates them contralaterally
Semispinalis Thoracis
- Transverse to spinous processes in thoracic region
* extend head, thoracic and cervical regions, rotates them contralaterally
Multifidus
- cover lamina and span vertebral segments from sacrum all the way to 2nd cervical
- originate on transverse processes and insert on spinous
- easiest to see in lumbar region
- Actions: stabilizes vertebrae during localized movements of vertebral column
Rotatores Brevis
- transverse process of one vertebra to base of spinous process of next vertebra above (spans one intervertebral joint)
- Action: extend head, thoracic and cervical regions, rotates them contralaterally
Rotatores Longus
- transverse process of one vertebra to spinous process of 2nd vertebra above (spans 2 intervertebral joints)
- Actions: extend head, thoracic and cervical regions, rotates them cotnralaterally
Interspinales
•Innervation: dorsal rami of spinal nerves
Intertransversari
• Innervation: dorsal and ventral rami of spinal nerves!!!!
Levator Costarum
•Innervations: ventral and dorsal rami of C8-T11 s. nerves
Suboccipital Triangels bones
•Atlas (C1) and Axis (C2)
Suboccipital Region Muscles
- Rectus capitis posterior major and minor, obliquus capitis superior and inferior
- mainly posterior muscles, aid in extension and rotation at atlantoaxial joint
- All are innervated by suboccipital nerves (dorsal rami of C1)
Occipital Neuralgia
- Caused by irritation of greater occipital (dorsal rami C2) and lesser occipital nerves (ventral rami C2)
- Symptoms include neck pain that spreads radiates upward and around the sides of the head, following the C2 dermatome
