Deep back Flashcards
Are the deep back muscles intrinsic or extrinsic (explain)
- Intrinsic ( they originate and insert in the back )
What are the main muscle groups of the deep back
- ) Splenius (most superficial)
- ) Erector spinae (intermediate)
- ) Transversospinales (deepest)
MInor muscles of the deep back
- ) Interspinales
- ) Intertransversarii (might be innervated by medial dorsal nerve)
- ) levatores costarum
In general what actions do all deep back muscles perform
Extensors- extension of the spine/head (ALL)
CAN assist with…
- lateral felxion (side bending) of VC or head/neck
- smaller muscles are stabilizers and proprioceptors
Thoracolumbar facia and the deep back
- deep fascia of the thorasic and lumbar regions
- covers erector spinae muscle group
- thicker in the lumbar region compared to throasic region
Thoracolumbar facia in the thoracic region
location, attachment
- deep to the extrinsic (superficial back) muscles
- attaches to thoracic spinous processes and to the rib angles
Thoracolumbar facia in the lumbar region (location, attachment)
- thicker (three layers)
- fuses laterally with aponeuroses of lateral abdominal muscles and superficial back muscles
Posterior Thoracolumbar facia attachment
- lumbar spinious processes
- median sacral crest
- superior illium
Middle Thoracolumbar facia attachment
- lumbar transverse processes
Anterior Thorocolumbar facia attachment
- lumbar transverse processes
Muscles in the Spinotransversales group
- Splenius Capitus
- Splenius Cervicis
Splenius capitus (location, O and I)
- deep to the trapezius
- fibers run superolaterally (perpendicular) to upper trap fibers
- Origin:
Inferior half of ligamentum nuchae
spinous processes (C7-T4)
- Insertion:
Mastoid process
lateral 1/3 of superior nuchal line
-
Splenius capitus action
- unilateral: lateral flexion (side bend)
Ipsilateral rot. head and neck - Bilateral: extend head and neck
Splenius cervicis (location, O and I)
- separates from splenius capitus around T3 area
- Orientation: spinous processes (T3-T6)
- Insertion : posterior tubercles of the transverse processes of C1-C4
Splenius cervicic action
- unilateral: lateral flex (side bend)
ipsilateral rot. neck
-bilateral: extension
Erector Spinae muscles
- ) Illiocostalis
- ) Longissims
- ) Spinalis
all have common orientation in lower segments = thoracolumbar fascia
Illiocostalis
- most lateral
Origin thoracolumbar fascia
Insertion: Rib angles and cervical transverse processes (C4-C6)
Illiocostalis action
Unilateral: Lateral flex (side bend)
Bilateral: Extension
Longissimus (location, O and I)
- medial to the illiocostalis
- spans sacrum to skull
Origin: thoracodorsal lumbar
thorasic spinous processes
Insertion: medial to the rib angles
transverse processes (C and T)
mastoid process
Longissimus action
Unilaterally: lateral flex (side bend)
Ipsilateral rot. head and neck
Bilateral: extends column
Spinalis (location, O and I)
- most medial
- arches between spinous processes
- arches across 6-10 vertebra
Origin/Insertion : attaches between spinous
processes ( O and I)
ligamentum nuchae (O)
Spinalis action
Extend the vertebral column
Transversopinalis muscle group
location, general O& I, and action
- deep to the erector spinous group
- fibers slant superomedially
General O: Mamillary processes (L)
Transverse processes (T)
Articular processes (C)
General I: Spinous process of more superior
vertebra
Action:
Unilateral: lateral flexion (side
bending)
Contralateral rotation
Stabilizers
Proprioceptors
Muscles included in Transversospinalis muscle group
- ) Semispenalis
- ) Multifidus
- ) Rotatores
Semispenalis (description and action)
- spans half the spine
- spans in 4-6 vertebral segments
- divided into thoracis, cervicis, and capitis
- Action:
-Unilateral: thorasics/cervicis
contralaterally rotate- Bilaterally- extend the vertebral column
Multifundis
- spans 2-4 vertebral segments
- robust in the lumbar region (deep to
erector spinae) - more superiorly it is deep to the
semispenalis
