Muscles of Vertebral Column, Superficial Back, Deep Back and Suboccipital Region Flashcards Preview

Gross Anatomy > Muscles of Vertebral Column, Superficial Back, Deep Back and Suboccipital Region > Flashcards

Flashcards in Muscles of Vertebral Column, Superficial Back, Deep Back and Suboccipital Region Deck (17):
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Trapezius Origin? Insertion? Innervation? Action?

O: Medial third of superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7-T12 vertebrae.

I: Lateral third of clavicle, acromion, and spine of scapula.

Innervation: Spinal accessory nerve (CN11 - motor fibers) C3-C4 of cervical plexus (pain and proprioceptive fibers).

Action:
Descending - elevates scapula
Ascending - depresses scapula
Transverse (or all parts together) - retracts scapula; descending and ascending parts act together to rotate glenoid cavity superiorly

1

Latissimus dorsi Origin? Insertion? Innervation? Action?

O: Spinous processes of T7-T12, thoracolumbar fascia, iliac crest, and inferior 3 or 4 ribs.

I: Floor of intertubercular sulcus (groove) of humerus

Innervation: Thoracodorsal nerve (C6-C8)

Action: Internal rotation, adduction, extension, respiration (Cough muscle), raises body during climbing

2

Splenius capitis origin? Insertion? Innervation? Action?

O: Arises from nuchal ligament and spinous processes of C7-T3 or T4

I: Mastoid process, lateral superior nuchal line

Innervation: Posterior rami of spinal nerves

Action:
Alone-> Laterally flex neck and rotate head to side of active muscles
Together-> Extend head and neck

3

Splenius cervicis origin? Insertion? Innervation? Action?

O: Arises from nuchal ligament and spinous processes of C7-T3 or T4

I: Tubercles of transverse processes of C1-C3 vertebrae

Innervation: Posterior rami of spinal nerves

Action:
Alone-> Laterally flex neck and rotate head to side of active muscles
Together-> Extend head and neck

4

Levator scapulae Origin? Insertion? Innervation? Action?

O: Posterior tubercles of transverse processes of C1-C4

I: Medial border of scapula superior to root of spine.

Innervation:
Dorsalscapular nerve (C5) and cervical nerves (C3-C4)

Acton: Elevates scapula and tilts its glenoid cavity inferiorly by rotating scapula.

5

Longissimus capitis, cervicis, and thoracis Origin? Insertion? Innervation? Action?

O: Arises by broad tendon from posterior part of iliac crest, posterior surface of sacrum, sacro-iliac ligaments, sacral and inferior lumbar spinous processes, and supraspinous ligament.

I: Fibers run superiorly to ribs between tubercles and angles to transverse processes in thoracic and cervical regions and to mastoid process of temporal bone.

Innervation: Posterior rami of spinal nerves

Action:
Bilateral-> Extend vertebral column and head; as back is flexed, control movement by gradually lengthening their fibers
Unilateral-> Laterally flex vertebral column

6

Rhomboid minor Origin? Insertion? Innervation? Action?

O: Nuchal ligament; spinous processes of C7 and T1 vertebrae

I: Triangular area at medial end of scapular spine.

Innervation: Dorsal scapular nerve (C4-C5)

Action: Retracts scapula and rotates it to depress glenoid cavity; fixes scapula to thoracic wall.

7

Spinalis capitis, cervicis, and thoracis Origin? Insertion? Innervation? Action?

O: Arises by broad tendon from posterior part of iliac crest, posterior surface of sacrum, sacro-iliac ligaments, sacral and inferior lumbar spinous processes, and supraspinous ligament.

I: Fibers run superiorly to spinous processes in upper thoracic region and to cranium.

Innervation: Posterior rami of spinal nerves

Action:
Bilateral-> Extend vertebral column and head; as back is flexed, control movement by gradually lengthening their fibers
Unilateral-> Laterally flex vertebral column

8

Illiocostalis cervicis, thoracis and lumborum Origin? Insertion? Innervation? Action?

O: Arises by broad tendon from posterior part of iliac crest, posterior surface of sacrum, sacro-iliac ligaments, sacral and inferior lumbar spinous processes, and supraspinous ligament.

I: fibers run superiorly to angles of lower ribs and cervical transverse processes.

Innervation: Posterior rami of spinal nerves

Action:
Bilateral-> Extend vertebral column and head; as back is flexed, control movement by gradually lengthening their fibers
Unilateral-> Laterally flex vertebral column

9

Rectus capitis posterior major Origin? Insertion? Innervation? Action?

O: C2 spinous process

I: Lateral part of the inferior nuchal line of occipital bone.

Innervation: Suboccipital nerve (C1) (posterior ramus)

Action: Bilateral-> extends head Unilateral-> rotates head to same side

10

Multifidus Origin? Insertion? Innervation? Action?

O: Arise from posterior sacrum, posterior superior iliac spine of ilium, aponeurosis of erector spinae, sacro-iliac ligaments, mammillary processes of lumbar vertebrae, transverse processes of T1-T3 and articular processes of C4-C7.

I: Thickest in lumbar region, fibers pass obliquely superomedially to entire length of spinous processes of vertebrae located 2-4 segments superior to origin.

Innervation: Posterior rami of spinal nerve

Action: Unilateral contraction rotates to contralateral side; stabilizes vertebrae during local movements of vertebral column

11

Semispinalis thoracis, cervicis, and capitis Origin? Insertion? Innervation? Action?

O: Arise from transverse processes of C4-T10 vertebrae

I: Fibers run superomedially to occipital bone and spinous process in upper thoracic and cervical regions, spanning 4-6 segments.

Innervation: Posterior rami of spinal nerve

Action: Extends head and thoracic and cervical regions of vertebral column and rotates them contralaterally.

12

Rectus capitis posterior minor Origin? Insertion? Innervation? Action?

O: C1 posterior tubercle

I: Medial third of inferior nuchal line.

Innervation: Suboccipital nerve (C1) (posterior ramus)

Action: Bilateral-> extends head Unilateral-> rotates head to same side

13

Rotatores longi and brevis Origin? Insertion? Innervation? Action?

O: Arise from transverse processes of vertebrae; are best developed in thoracic region

I: Fibers pass superomedially to attach to junction of lamina and transverse process or spinous process of vertebrae immediately (brevis) or 2 segments (longus) superior to vertebra of origin.

Innervation: Posterior rami of spinal nerve

Action: May function as organs of proprioception; possibly stabilize vertebrae and assist with local extension and rotatory movements of vertebral column

14

Obliquus capitis superior Origin? Insertion? Innervation? Action?

O: C1 transverse process

I: Occipital bone between the superior and inferior nuchal lines.

Innervation: Suboccipital nerve (C1) (posterior ramus)

Action: Bilateral-> extends head Unilateral-> tilts head to same side, rotates to opposite side

15

Obliquus capitis inferior Origin? Insertion? Innervation? Action?

O: C2 spinous process

I: C1 transverse process

Innervation: Suboccipital nerve (C1) (posterior ramus)

Action: Bilateral-> extends head Unilateral-> rotates head to same side

16

Rhomboid major Origin? Insertion? Innervation? Action?

O: Spinous processes of T2-T5 vertebrae

I: Medial border of scapula from level of spine to inferior angle

Innervation: Dorsal scapular nerve (C4-C5)

Action: Retracts scapula and rotates it to depress glenoid cavity; fixes scapula to thoracic wall.