back & anterior abdominal wall Flashcards
what are the 3 layers of the thoracolumbar fascia?
- the posterior layer
- middle layer
- anterior layer
describe the posterior layer of the thoracolumbar fascia
- covers the erector spinae
- extends up to the lower neck
- reinforced by the latissimus dorsi
- medially attached to the spinous processes of the lumbar and sacral vertebrae
what are the functions of the thoracolumbar fascia?
- involved in mvt and load transfer between the trunk and limbs
- houses several deep muscles of the back
- contains a number of nociceptors which may be responsible for some back pain
describe the middle layer of the thoracolumbar fascia
- middle layer is attacged medially to the tips of the transverse processes and laterally to the iliac crest & 12th rib
- lies between the quadratus lumborum and erector spinae
Describe the** anterior layer **of the thoracolumbar fascia
- this layer is attached to the lumbar transverse processes and iliocolumbar ligament
- extends from iliac crest to rib 12
- lies anterior to quadratus lumborum muscles and seperates it from the psoas major muscle
what are the 3 groups of muscles in the back?
- superficial group - associated with mvts of the shoulder
- intermediate group- associated with mvts of the thoracic cage
- deep group- associated with mvts of the vertebral column
what are the superficial muscles of the back?
- trapezius
- Latissimus dorsi
- rhomboids
- levator scapulae
what are the intermediate back muscles?
- serratus posterior superior
- serratus posterior inferior
what nerve innervates the trapezius muscle?
spinal accessory nerve (cranial nerve 11)
what nerve innervates the latissimus dorsi?
thoracodorsal nerve
what nerve innervates the rhomboids and the levator scapulae?
- dorsal scapular nerve - branch off c5
what are the intrinsic muscles of the back responsible for?
- posture and control of the spinal column
how are the deep muscles of the back divided?
3 groups
1. splenius muscles (superfical - 2muscles)
2. erector spinae (intermediate - 3 muscles)
3. transversospinal muscles (deep - 3 muscles)
what are the 2 deep back muscles in the splenius group?
- splenius cervicis
- splenius capitus
Describe the origin and the insertion of the splenius capitus muscle?
O: spinous processes of C7-T3 & the lower half of the nuchal ligament
I: inserts onto the mastoid process and the superior nuchal line of the occipital bone
what is the origin and insertion of the splenius cervicis muscle?
o: spinous processes of vertebrae T3-T6
I: inserts onto the transverse processes of C1-C4
what are the 3 erector spinae muscles (intermediate group of the deep muscles of the back)?
- iliocostalis
- longissimus
- spinalis
what are the actions of the erector spinae?
- extends the head and part of all of the vertebral column
- laterally flexes the head
- longissimus rotates the head
- straightends the flexed spine
what is the deep deep layer of the muscles of the back also called?
also called the transversospinalis group
what groups of muscles are in the deep deep group of muscles in the back / the transversospinalis group?
- semispinalis
- multifidus
- rotatores
Describe the semispinalis group of the deep deep group of the back
- most superficial
- attaches onto the occipital bone of the skull and runs through the thoracic and cervical regions of the spinal column
what are the 3 muscles in the semispinalis (deep deep muscle group of the back)?
- semispinalis thoracis
- semispinalis cervicis
- semispinalis capitus
which layer does the multifudus muscle of the back belong to?
the intermediate layer of the deep muscle group
what are the origins and insertions of the multifidus group?
- O: sacral, lumbar , thoracic and cervical vertebrae (transverse processes)
- I: tips of the spinous processes
