619 Lab 8/27 Deep Back Anatomy

C2

landmark for intrinsic back muscles, attaches to semispinalis cervicis, muscles of suboccipital triangle are just below it

Each Muscle of the Erector Spinae Group is Named for the Superior Attachment of its Fibers

lumbar vertebra = lumbar subgroup

thoracic vertebra = thoracis subgroup

cervical vertebra = cervicis subgroup

skull = capitis subgroup

3 Erector Spinae Muscles (medial to lateral)

spinalis

longissimus

iliocostalis

Functions of Erector Spinae Muscles

bilateral contraction to pull the trunk into extension or hold the trunk stable during any degre of flexion

unilateral contraction side-bends the torso to the ipsilateral side

Spinalis Muscle Group

Location of Spinalis Muscle Group

medial to longissimus muscle group, deep to latissimus dorsi and serratus posterior inferior

Longissimus Muscle Group

Location of Longissimus Muscle Group

intermediate of iliocoastalis and spinalis, deep to latissimus dorsi and serratus posterior inferior

Iliocostalis Muscle Group

Location of Iliocostalis Muscle Group

lateral to longissimus muscle group, deep to latissimus dorsi and serratus posterior inferior

3 Transversospinals Muscles

semispinalis (capitis and cervicis)

multifidus lumborum

rotatores

Function of Semispinalis Muscles

extensors of the neck and skull, lonest of the transversospinalis muscles

Function of Multifidus Lumborum Muscle

major extensor and posterior stabilizer of the lumbar vertebrae, minor rotary role in the lumbar region

Function of Rotatores Muscles

have the most rotary action of the transversospinalis muscles but are the smallest (arise from transverse processes of te vertebra and are best visualized in the thoracic region, span 1-2 vertebral segments)

Semispinalis Capitis Muscle

Semispinalis Cervicis Muscle

Location of Semispinals Cervicis

deep to the semispinalis capitis/splenius/trapezius, superficial to the multifundus and rotatores

Location of Semispinalis Capitis

superior to semispinalis cervicis, deep to splenius and trapezius

Multifundus Lumborum Muscle

Rotatores Muscle

Attachements of Iliolumbar Ligament

between the lumbar transverse processes and ilium

Muscles and Structures of Suboccipital Ligament

obliquus capitis superior muscle

obliquus capitis inferior muscle

rectus capitis posterior major muscle

rectus capitis posterior minor muscle

suboccipital nerve

vertebral artery

semispinalis cervicis muscle

semisplicanlis capitis muscle

greater occipital nerve

Location of Suboccipital Nerve

within the suboccipital triangle formed by the rectus capitis posterior major, obliquus capitis superior muscle, and obliquus capitis inferior muscle

deep to the semispinalis capitis

Location of Vertebral Artery

within the suboccipital triangle formed by the rectus capitis posterior major, obliquus capitis superior muscle, and obliquus capitis inferior muscle

often deep to the suboccipital nerve

Suboccipital Nerve

Vertebral Artery

Obliquus Capitis Superior Muscle

Obliquus Capitis Inferior Muscle

Rectus Capitis Posterior Minor

Rectus Capitis Posterior Major

Location of Rectus Capitis Posterior Major

intermediate to rectus capitis posterior minor and obliquus capitis superior, supeiror to obliquus capitis inferior, deep to the semispinalis capitis and splenius capitis

Location of Rectus Capitis Posterior Minor

most medial of the occipital muscles, superior to rectus capitis posterior major and obliquus capitis inferior, deep to the semispinalis capitis and splenius capitis

Location of Obliquus Capitis Inferior Muscle

most inferior occipital muscle (inferior to obliquus capitis superior, and both rectus capitis posteriors), deep to the trapezius splenius capitis and semispinalis capitis

Location of Obliquus Capitis Superior Muscle

most lateral occipital muscle

deep to semispinalis capitis, splenius capitis, and longissimus capitis

Greater Occipital Nerve

Location of Greater Occipital Nerve

medial to most of occipital triangle muscles except the rectus capitis posterior minor, deep to the trapezius muscle, pierces the semispinalis capitis muscle

2 Muscles Innervated by the Greater Occipital Nerve

semispinalis capitis and obliquus capitis inferior

4 Muscles Innervated by the Suboccipital Nerve

rectus capitis posterior major

rectus capitis posterior minor

obliquus capitis supeiror

obliquus capitis inferior

Muslces Supplied by the Vertebral Artery

suboccipital muscles

How to Differentiate the Rotatores

only cross over 1-2 vertebrae

Erector Spinae Muscle Dysfunction

can cause restriction in the sacrum because of their common attachment to the sacrum

sacral dysfunctions should be evaluated for erector spinae dysfunctions

What types of muscles often cause type 1 dysfunctions in the lower back?

long restrictors, because they ross two or more vertebral segments

5 Muscles that can Cause Type 1 Dysfunctions

iliocostalis

semispinalis

longissimus

multifundus

rotatores longi

Muscle That can Cause Type 2 Dysfunctions

rotatores breves

Dura Mater

tough, fibrous membrane that surround the brain, spinal cord, and nerve roots

stretches from the foramen magnum of the occiput and C2 down to S2 and the coccyx

Dura Mater Dysfunction

since it spans almost the entire spinal cord, dysfunction in the sacrum may manifest in other areas of the spine such as the cranium