Anatomy: Intrinsic muscles of the back
What are the attachments of rectus capitis posterior minor?
inferior nuchal line to posterior tubercle C1
What is the innervation and blood supply of the suboccipital muscles?
innervation: suboccipital nerve (C1 posterior ramus) blood supply: vertebral and occipital arteries
What are the intersegmental muscles?
intertransversii and interspinales (true segmental) levatores costarum
Describe the middle layer of the thoracolumbar fascia
separates deep back muscles from posterior abdominal wall (quadratus)
What is the unilateral and bilateral action of erector spinae?
unilateral: lateral flexion of the spine bilateral: extension of the spine *main extensors of the vertebral column*
What is the unilateral and bilateral action of transversospinales?
unilateral: rotation to the opposite side bilateral: support
Where is the suboccipital region found?
associated with posterior aspects of C1 (atlas) and C2 (axis) deep to semispinalis capitis
What are the attachments of obliquus capitis superior?
between superior and inferior nuchal lines to transverse process C1
What is the cervical myodural bridge?
connection between cervical dura and CT of suboccipital muscles implications in movements of CSF possible cause of cervicogenic headaches
What muscles are covered by thoracolumbar fascia?
intrinsic back muscles
A 35-year-old female presents with the chief complaint of upper back discomfort. Physical exam reveals that T3 - T8 vertebra are SL [side-bent left] and RR [rotated right]. what muscle is responsible?
left semispinalis
What muscles form the suboccipital triangle?
rectus capitis posterior major, obliqus capitis inferior, obliqus capitis superior
Describe the anterior layer of thoracolumbar fascia
separates abdominal cavity from posterior abdominal wall
What is the action of intertransversarii and interspinales?
support
What is the function of the suboccipital muscles?
support of the head in the upper cervical region extension of the head on the neck, lateral flexion
Label the parts of the following
thoracolumbar fascia (anterior middle and posterior) slide 5 for reference
What are the attachments of obliquus capitis inferior?
transverse process C1 to spinous process C2
What are the contents of the suboccipital triangle
vertebral artery and suboccipital nerve (C1)
What are the three layers of throacolumbar fascia and where will they terminate?
Anterior, middle, and posterior terminate at attachment of transversus abdominus muscle
Describe rotation of vertebrae
Direction of the body is used for direction Dysfunction will rotate vertebrae to left if it is on right and right if it is on left
What superficial back muscle will attach to thoracolumbar fascia?
Latissimus dorsi
What are the proximal and distal attachments of splenius cervicis?
P: SP's T3-T6 D: TP's C1-C3
What are the proximal and distal attachments of splenius capitis?
P: nuchal ligament and SPs C7-T4 D: mastoid process and superior nuchal line
What is the function of the greater occipital nerve, and what is the clinical relevance?
POsterior ramus of C2 is strictly sensory to the back of the head transverses semispinalis capitis : dysfunction in this muscle can lead to sensory issues on back of head
What is the attachment of iliocostalis?
Proximal: ileum, sacrum, lumbar Distal: ribs
What muscles form transversospinales?
Semispinalis, multifidus, and rotatores transverse process to spinous process
What are the attachments of rectus captis posterior major
inferior nuchal line to spinous process C2
What are the attachments of semispinalis capitis?
Tp's C7-T6 to occipital bone
Where is semispinalis found and how many vertebrae does it span?
most prominent in thoracic region spans 4-6 vertebrae
Describe the posterior layer of thoracolumbar fascia
most superficial, covers deep back muscles
What is the function of the suboccipital nerve?
motor to the muscles of the SOT, NO cutaneous sensory branch
Where is multifidus found and how many vertebrae does it span?
most prominent in lumbar region spans 2-4 vertebrae
What is a suboccipital release?
place pressure on back of skull in order to release semispinalis capitis muscle and relieve tension on greater occipital nerve (posterior rami C2)
What are the intrinsic back muscles innervated by? What covers these muscles
posterior rami of spinal nerves covered by throacolumbar fascia
Label the suboccipital muscles
slide 14 for reference
What are the unilateral and bilateral axions of spinotransversales?
splenius capitis and cervicis unilateral: rotation to ipsilateral side, lateral flexion bilateral action: extension of head and neck
What muscles compose spinotransversales?
splenius capitis and splenius cervicis
What muscles are included in erector spinae?
Iliocostalis, Longissimus, and spinalis
A 52-year-old male presents with the chief complaint of lower back pain. Physical exam reveals that his L1 vertebra is rotated on L2; SL [side-bent left] and RL [rotated left]. what muscle is responsible?
Right rotatores
What are the attachments of thoracolumbar fascia?
Superior: continuous with deep fascia of neck Inferior: lower border of Rib 12 and iliac crest Medial: spinous and transverse processes Lateral: angles of ribs and lateral abdominal wall muscles
What do the intrinsic back muscles act on?
act on vertebral column and skull
Where is rotatores and how many vertebrae does it span?
all throughout vertebral column spans 1-2 vertebrae
What are the attachments of longissimus?
proximal: ileum, sacrum, lumbar distal: mastoid process and transverse process
What is the action of levatores costarum?
elevates ribs (TP to ribs at thoracic region) *accessory respiratory muscles*
What is the blood supply to spinotransversales?
occipital and segmental arteries (come out at every level and supply body wall
What are the attachments of spinalis?
p: ileum, sacrum, lumbar d: spinous processes
