Download Soft Tissue of the Back

Soft Tissue of the Back
Innervation
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As a general rule, muscles associated
with the back are innervated by the
dorsal rami of the spinal nerves
They are innervated segmentally and
near their origin
Only a couple of exceptions
Innervation
Innervation
The Exceptions
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Serratus Posterior Superior
• Lig. Nuchae and spinous processes of C7-T3
to 2nd to 5th ribs
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Serratus Posterior Inferior
• Spinous Proceses of T11-L2 to inferior
borders of last 4 ribs
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Elevate or depress ribs (accessory
respiratory muscles)
Innervated by ventral rami
Serratus Post.
Major Groups of Back Muscles
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Those that arise from the mid-line and
run superiorly and laterally – The
Splenius Muscles (Bandage)
Those that arise from near the mid-line
or slightly laterally and run almost
longitudinally with no marked inward or
outward slant – called the Erector
Spinae
Major Groups
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The third group are those that arise
laterally and run towards the mid-line as
they travel up
• Called the Transversospinalis group
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Last – small muscles that run from one
spinous process to another or one
transverse process to another
(interspinales and intertransvesus)
Splenius Muscles
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Splenius Capitis
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Lig. Nuchae and Spinous Process of C7-T4 to sup. Nuchal
line and mastoid process
Splenius Cervicis
•
Spinous processes of T3-T6 to Transvers process of C2-C4
Both extend head and neck and can laterally flex
(side bend) the head; Also support and can
contribute to rotation of cervical spine and, thus, the
head
Dorsal rami of spinal nerves nearest their respective
origins
Splenius
Erector Spinae
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Long Muscles with multiple, overlapping,
origins
Three sub groups; iliocostalis, longissimus,
spinalis
Common “origin” of the entire group is a
muscle mass located on the posterior sacrum,
iliac crest, and spinous process of lumbar
vertebrae
Beyond that, specific muscles have various
attachments
Erector Spinae
E. Spinae
E. Spinae
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The three groups are broken down into
sub -subgroups based upon where they
are located
E.G., in the lumbar region called
lumborum, in thoracic region called
thoracis, in cervical region called cervicis
and, if they reach anywhere on the skull,
they are called capitis.
E.G., Iliocostalis lumborum
E. Spinae
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Overlap or multiple attachments
Despite the common “origin” of the
group, most muscles have various and
multiple origins and insertions
These tend to overlap so that the group
can traverse a large length of the back
Some components will attach as an
insertion while new fibers will originate
from the same region
E. Spinae
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For example, the iliocostalis lumborum
muscles will attach to the lower six ribs while
the iliocostalis thoracis will originate from the
lower six ribs and insert on the upper six ribs
Likewise the iliocostalis cervicis will originate
from the upper six ribs and insert on the
transverse process of C4 thru C6
All are innervated by the dorsal rami of the
nerves nearest their origin – e.g., iliocostalis
thoracis will be innervated by the lower
thoracic nerves (T6-T12)
Longissimus
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Generally, run from the transverse
processes of one level of v. column up
several levels to attach to another
transverse process
The longissimus capitis originates on t.
processes of T1-T4 and attach to the
skull at the mastoid process, hence the
name capitis
Is the only E.Spinae to attach to skull
Spinalis
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E. Spinae nearest the mid-line, hence,
the name spinalis
The spinalis group run from spines of
one group of vetebrae to spines of v.
several segments up
Most prominent in thoracic spine but also
located in cervical and lumbar spine
General, Collective, Function of
E. Spinae
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To support spine (anti-gravity)
To extend spine
To laterally flex spine (side bend)
To rotate the spine
They work together
Transversospinalis Group
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Arise laterally and run, more or less, to the
mid-line
Semispinalis Capitis
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Transverse Process C7-T6 to Occipital bone, near
mid-line, Extend head, rotate to same side
Semispinalis Cervicis
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Transverse process T1-T6 to Spines of C2-C6, Extend
head (Cervical Spine) and side bend
Semispinalis
Semispinalis
Transversospinalis Group
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Multifidi
From the sacrum, and transverse
process of L., T. and lower C vertebrae
to Spinous Process of Lumbar, thoracic
and cervical vetebrae 2 or 3 levels up
Very large and obvious in lumbar region
Support V. column. May contribute to
minor motions (lat. flex., rot., ext.)
Rotatores
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Transverse processes of 2nd cervical to
sacrum to lamina on vertebrae above
origin (one segment)
Same function as multifidi
Interspinous and
Intertransversus
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Run between spinous processes or
transverse processes
Blend with ligaments of same name
Perform same function (Stability)
Small Muscles
Muscles mostly associated with
the head
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Sub-Occipital (Posterior) Triangle very small,
support head on v. column, minor motions
Rectus Capitis Post. Major
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Spinous process of C2 to Lateral aspect of nuchal line
Dorsal ramus of suboccipital nerve
Rectus capitis Post. Minor
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Post. Arch of atlas (C1) to med. aspect of inferior
nuchal line
Dorsal ramus of suboccipital nerve
Sub-Occ. Triangle
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Obliqus Capitis Superior
• Transverse process Atlas to a point between
sup. and inf. Nuchal line
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Obliqus Capitis Inferior
• Spinous Process Axis to transverse process
atlas
Suboccipital Triangle
Anterior Muscles – all
innervated by Ventral Rami
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Sterno-Cleido-Mastoid
Manubrium (S) and Medial ½ clavicle to
mastoid process
Together – head flexion, unilaterally, side
bending (same side) rotation (opposite
side)
CN XI and ventral rami of C2, C3
SCM
SCM - Anterior
Scaleni-AKA Pre-Vertebral
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Scalaneus Anterior
Ant tubercle of transverse process of C2-C6
Scalene tubercle of anterior surface of 1st rib
Flex and rotate spine
Reverse action = accessory respiratory muscle
by raising 1st rib.
ventral rami C2-C6
Pre-Vertebrals
Scaleni
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Scaleneus Medius from post. tubercle of
transverse processes C2-C7 to sup.
surface of 1st rib behind subclavian
groove
Scaleneus Posterior from post. tubercles
of transverse processes C4-C6 to lateral
superior surface of 2nd rib
Flex, rotate elevate rib
Pre-Vertebral
Longus Coli
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Bodies of C5-T3 to bodies of C2-C4
Bilaterally flexes cervical v., unilaterally
rotates rotate and side bend
C2-C8 innervation
Longus Capitis
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Ant. Tubercles of transverse processes
of C3-C6
To inferior surface of basilar portion of
occipital bone
Flex, c. v. and head rotate and flex c. v.
Anterior Small Muscles
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Rectus Capitis Anterior
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Rectus Capitis Lateralis
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Ant. Surface of lateral mass of the atlas to inf. Surface
of occipital bone anterior to foramen magnum
C1 – C2
Sup surface of transverse process of atlas to inferior
surface of jugular process, occipital bone
C1-C2
Both support skull
Anterior Sub Occipital Muscles
Cervical Plexus
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A small plexus originating from the
ventral rami of C1-C4 with some
contribution from C5
Mostly cutaneous type nerves
One notable somatic motor nerve = the
Phrenic nerve to the diaphragm muscle
The other motor nerves work with cranial
nerves to innervate hyoid type muscles
Cervical Plexus
Cervical Plexus
Cervical Plexus
Cervical Plexus
Phrenic Nerve in Thorax
Phrenic Nerve
Cervical Plexus
Suprahyoids
Infrahyoids
Comparison