Deep Back Flashcards
Splenius capitis origin
Ligament nuchae
Spinous process of C7-T3
Splenius capitis insertion
Occipital bone, mastoid process
Splenius cervicis origin
Spinous process of T3-T6
Splenius cervicis insertion
Transverse process of C2-C4
Iliocostalis lumborum origin
Common tendon of erector spinae
Iliocostalis lumborum insertion
Angle of ribs 6-12
Iliocostalis thoracis origin
Lower 6 ribs
Iliocostalis thoracis insertion
upper 6 ribs
Iliocostalis cervicis origin
Ribs 3-6
Iliocostalis cervicis insertion
Transverse process of C4-C6
Longissimus thoracis origin
Part of common tendon of erector spinae group
Longissimus thoracis insertion
Lower 9 ribs
Longissimus cervicis origin
Transverse process of T1-T5
Longissimus cervicis insertion
Transverse process of C2-C6
Longissimus capitis origin
Tendon of insertion of longissimus cervicis (C2-C6)
Longissimus capitis insertion
Mastoid process
Spinalis thoracis origin
Spine of T11-L2
Spinalis thoracis insertion
Spine of T1-T4
Semispinalis cervicis origin
Transverse process of T1-T6
Semispinalis cervicis insertion
Spine of C2-C5
Semispinalis capitis origin
Transverse and articular processes of T1-T6
Semispinalis capitis insertion
Occipital bone
Long rotators origin
Transverse processes
Long rotators insertion
Spinous processes of 2nd vertebrae above
Short rotators origin
Transverse processes
Short rotators insertion
Spinous process of vertebrae above
Oblique capitis inferior origin
Spine of axis (C2)
Oblique capitis inferior insertion
Transverse process of atlas (C1)
Oblique capitis superior origin
Transverse process of atlas (C1)
Oblique capitis superior insertion
Occipital bone
Rectus capitis posterior major origin
Spine of axis (C2)
Rectus capitis posterior major insertion
Occipital bone
Rectus capitis posterior minor origin
Posterior tubercle of atlas (C1)
Rectus capitis posterior minor insertion
Occipital bone
Muscles of deep back develop from
mesoderm germ layer - myoblast cells
Myotomes divide into
Epaxial (dorsal) division
Hypaxial (ventral) division
Muscles derived from epaxial division are
Deep extensor muscles of back
Nerves supplying epaxial division muscles are
dorsal primary rami of spinal nerves
Nerves supplying hypaxial division are
ventral primary rami
Muscles derived from hypaxial division are
Infrahyoid
Flexor muscles of vertebral column
Quadratus lumborum
Deep back muscles function to
maintain posture and balance
move back - flexsion, extension, rotation
Back strains
results from extensive extension and rotation
microscopic tearing of muscle cells or ligaments
Splenius group
posterior midline of back
proceeds laterally and superiorly to insertion
Most superficial intrinsic muscles of posterior part of neck
Erector spinae group
posterior midline of back or more laterally
rung longitudinally
Largest muscle mass of back
Transversospinalis group
arise laterally
travel toward midline to insertion
deeper to erector spinae group
originate from transverse processes and proceed to spinous processes of more superiorly located vertebrae
Suboccipital muscles
movement of head and neck
Superficial layer
Erector spinae and splenius muscles
Intermediate layer
2 parts of Transversospinalis - semispinalis and multifidus
Deep layer
Segmental muscles and suboccipital muscles
Splenius capitis
partly covered by trapezius and SCM
Upper and larger of two splenius muscles
superiolaterally from origin and attach to skull
Splenius cervicis
narrow muscle below and parallel to splenius capitis
no fibers attach to skull
Common tendon of origin
attached to Sacrum, iliac crest, and spinous process of lumbar and last two thoracic vertebrae
Chief extensor of vertebral column is
Erector spinae group (Sacrospinalis)
Iliocostalis
associated with ribs
lumborum, thoracis, and cervicis parts
most lateral column of erector spinae group
Longissimus
associated with transverse processes of vertebrae
thoracis (largest part), cervicis, and capitis parts
Intermediate division
lower part blends with iliocostalis lumborum muscle
Spinalis
most medial and smallest division of erector spinae
usually only thoracic part is present
Spinous processes
Action of erector spinae group
Bilaterally extend head and vertebral column
Unilaterally laterally flex head and vertebral column
Chief extensor of vertebral column
Semispinalis
thoracis, cervicis, and capitis groups
span over 4-6 vertebrae
lacking in lumbar region
superficial to multifidus
Multifidus
Deeper to semispinalis
thickest in lumbar area, but present throughout back
Ends in cervical region
Sacral and lumbar areas covered by erector spinae; thoracic and cervical areas covered by semispinalis
Cover 2-4 vertebrae
Segmental muscles
Deepest part of transversospinalis group
Better developed in cervical and lumbar regions
Includes Interspinalis, Intertransversarii, and Rotators
Interspinalis
cervical and lumbar regions
Stretch between adjacent spinous processes from C2-T1/L1-L5
Intertransversarii
Run vertically between adjacent transverse processes
in cervical and lumbar regions
Rotators
Span one (short/Brevis) or two vertebrae (Long/Longus)
Best developed in thoracic region
Transverse to spinous processes
Suboccipital triangle formed by
Oblique capitis inferior, Oblique capitis superior, and Rectus capitis posterior major
All suboccipital muscles are supplied by
suboccipital nerve (dorsal ramus of C1)
Greater occipital nerve (dorsal ramus of C2) emerges from
below oblique capitis inferior & crosses muscle to innervate back of skull - sensory to posterior part of scalp
Does not innervate any muscles of suboccipital triangle
Flexion
anterior trunk m.
gravity
back muscles act as antagonist - gradually relax for smooth movement
Extension
All deep back muscles except intertransversarii
Lateral flexion
Intertransversarii m.
Splenius capitis and cervicis rotate head to same side and laterally flex neck
Erector spinae initiates lateral flexion unilaterally
Opposite side m. help by relaxing gradually
Rotation
Multifidi, rotators, and semispinalis m. rotate trunk to opposite side
Splenius and erector spinae extend trunk and rotate to same side
Oblique capitis inferior and rectus capitis posterior major/minor rotates atlas and turns head to same side
Oblique capitis superior and rectus capitis posterior major/minor extend head bilaterally and flex it to same side unilaterally