Back Myology Flashcards
Trapezius
Layer 1 O: Upper spine, occipital B. I: Scapula A: Whole muscle-retraction of scapula Upper part-elevation of scapula Lower part-depression of scapula Bilaterally: extension of neck Unilaterally: rotates face away, laterally flexes neck N: Spinal Accessory N. C3-C4 Blood supply: Transverse Cervical A.
Latissimus Dorsi M.
Layer 1 O: Lower spine I: front of humerus A: Medial rotation, ADduction, and extension of arm N: Thoracodorsal N. C6-C8 Blood supply: Thoracodorsal A.
Rhomboid Major M.
Layer 2 O: Thoracic spine I: Scapula (below spine) A: Retract and elevate scapula N: Dorsal Scapular N. C5 Blood supply: Dorsal Scapular A.
Rhomboid Minor M.
Layer 2 O: Spine cervical and thoracic I: Scapula at spine A: Retract and elevate scapula N: Dorsal Scapular N. C5 Blood supply: Dorsal scapular A.
Levator Scapulae M.
Layer 2 O: Cervical spine I: Scapula superior spine A: Elevates scapula, extend and laterally flex neck N: Dorsal Scapular N. C5 Blood supply: Dorsal scapular A.
Serratus posterior superior M.
Layer 3 O: Cervical and thoracic spine I: Superior surface of high ribs A: Elevate ribs w/ forced inspiration N: Intercostal N. Blood supply: Intercostal As.
Serratus posterior inferior M.
Layer 3 O: Thoracic and lumbar spine I: Inferior surface of low ribs A: Depresses ribs with forced expiration N: Anterior rami T9-T12 Blood supply: Intercostal As.
Splenius Capitis M.
Layer 4: Intrinsic O: Cervical vertebrae I: occipital and temporal Bs. A: Bilaterally-extend neck Unilaterally-laterally flex neck and rotate face toward N: Posterior rami C3-C5 Blood supply: Muscular branches of aorta
Splenius Cervicis M.
Layer 4: Intrinsic O: Thoracic vertebrae I: Cervical vertebrae A: Bilaterally-extend neck Unilaterally-laterally flex neck and rotate face toward N: Posterior rami C5-C7 Blood supply: muscular branches of aorta
Erector Spinae Ms.
Layer 5 Iliocostalis Longissimus Spinalis A: Bilaterally: Maintain posture and extend spine and head Unilaterally: Flex vertebral column N: Posterior rami
Iliocostalis M.
Layer 5
Most lateral
Lumborum, Thoracis, and Cervicis
Longissimus M.
Layer 5
Middle (not medial or lateral)
Thoracis, Cervicis, and Capitis
Spinalis M.
Layer 5
Medial
Thoracis, Cervicis, and Capitis
Rotatores Brevis M.
Layer 6
Extending to adjacent spinal segment
A: Extends and rotates spine away
N: posterior rami
Rotatores Longus M.
Layer 6
Extending 2 spinal segments superior
A: Extends and rotates spine away
N: Posterior rami
Multifidus M.
Layer 6
Extending 3 or 4 spinal segments
A: Extend and rotate spine away
N: Posterior rami
Semispinalis Ms.
Layer 6
Extending 5 or more spinal segments
Thoracis, Cervicis, and Capitis
Semispinalis Thoracis M.
Layer 6
O: Thoracic vertebrae (transverse processes)
I: Cervical and thoracic vertebrae (spinous processes)
A: Extend and rotate spine away
N: Posterior rami
Semispinalis Cervicis M.
Layer 6
O: Transverse processes of thoracic vertebrae
I: Spinous processes of cervical vertebrae
A: extend and rotate spine away
N: Posterior rami
Semispinalis Capitis M.
Layer 6 O: Transverse processes of cervical and thoracic vertebrae I: Occipital B. A: Extend head, rotate face away N: Posterior rami
Interspinalis M.
Deep back muscle O: Spinous process I: Adjacent spinous process A: Extend spine N: Posterior rami
Intratraversarii M.
Deep back muscle O: spinous process I: Adjacent transverse process A: Laterally flex spine N: Posterior portion=posterior rami, anterior portion=anterior rami
Levator Costarum Longus
Deep back muscle O: Transverse process C7-T11 I: 2nd rib inferior to origin A: Elevate ribs N: Posterior rami
Levator Costarum Brevis M.
Deep back muscle O: Transverse process C7-T11 I: Adjacent rib inferior to origin A: Elevate ribs N: Posterior rami
Rectus capitis posterior major M.
Medial border of Suboccipital triangle O: Spinous process C2 I: Lateral portion inferior nuchal line A: Extend head, rotate face toward N: Subbocipital N.
Rectus capitis posterior minor M.
O: posterior tubercle C1
I: below inferior nuchal line
A: Extend head
N: Subbocipital N.
Obliquus capitis inferior M.
Inferior border Suboccipital triangle Does not actually come in contact with skull O: spinous process C2 I: transverse process C1 A: rotate face toward N: Suboccipital N.
Obliquus capitis superior M.
Lateral border of Suboccipital triangle O: Transverse process C1 I: Between superior and inferior nuchal lines A: Extend and laterally flex head N: Subbocipital N.
