Deep Back Muscles Flashcards
What are the extrinsic back muscles?
The ones that connect lim to axial skeleton (superficial): trapezius, latissimus dorsi, levator scapulae, rhomboideus major and minor. AND the respiratory muscles (intermediate): serratus posterior superior and serratus posterior inferior
Superficial back muscles connect limb to axial skeleton and and innervated by CN XI. What are these extrinsic back muscles?
Trapezius Latissimus dorsi Levator scapulae Rhomboideus major Rhomboideus minor
Intermediate back muscles include respiratory muscles that include the serratus posterior group. What are these extrinsic back muscles?
Serratus posterior superior and serratus posterior inferior
What are the deep intrinsic back muscles?
Superficial: splenius capitus and splenius cervicis
Intermediate: iliocostalis, logissimus, and spinalis
Deep: semispinalis, multifidus, and rotatores
What are the epaxial muscles?
Spinalis
Longissimus
Iliocostalis
What are the hypaxial muscles?
Quadratus Lumborum External oblique Internal oblique Transversus Rectus abdominus
Serratus posterior superior origin
Ligamentum nuchae; spinous processes of C7 and T1-2
Serratus posterior superior insertion
Ribs 2-5
Serratus posterior superior action
Elevate upper ribs during inspiration
Serratus posterior inferior origin
Spinous processes of T11-12 and L1
Serratus posterior inferior insertion
Ribs 10-12
Serratus posterior inferior action
Pull lower ribs inferiorly and counteracts diaphragm
What are the 2 parts of the spinotrasversalis system?
Spenius capitis and splenius cervicis
The sacrospinalis sys aka…
Erector spinae
What are the 3 longitudinal bundles that form the sacrospinalis system
Iliocostalis, longissimus, and spinalis
What are the 3 groups of muscles that make up the transversospinalis system?
Semispinalis,multifidus, rotatores
Along either side of the midline of the back is innervated by
Dorsal rami of thoracic spinal nerves
More laterally along the back is innervated by
Lateral cutaneous branches of the intercostal nerves
Splenius capitis origin
Spinous processes of C7 and T1-4
Splenius capitis insertion
Superior nuchal line and mastoid
Splenius cervicis origin
Spinous processes of T3-6
Splenius cervicis insertion
C1-C4 transverse processes with levator scapulae
Iliocostalis is lateral/medial part of the erector spinae group?
Lateral
Iliocostalis extends back to do what for posture?
Keep erect
What are the components for iliocostalis?
Lumorum, thoracis, cervicis
Iliocostalis origin?
Ilium and sacrum
Iliocostalis insertion?
Most of the ribs
Longissimus is upper/middle/lower portion of erctor spinae group?
Middle
Longissimus components:
Thoracis, cervicis, capitis
Longissimus origin?
Transversus processes and sacrum
Longissimus insertion?
Most of ribs
Spinalis origin
Spinous processes of T11-L2
Spinalis insertion
Spinous processes of thoracic and lower cervical vertebrae
Multifidus are a thick muscle mass best seen in region of the
Sacrum
What are the 2 rotatores muscles and how many segments do they each span?
Long rotatores-spans 2 segments
Short rotatores-spans 1 segment
What are the 2 intrinsic segmental muscles?
Interspinales and intertransversarii
