MYOLOGY OF THE BACK Flashcards
Which of the muscles attaching to spinous processes represent layer one of the true back?
trapezius, latissimus dorsi
Which of the muscles attaching to spinous processes represent layer two of the true back?
rhomboid major, rhomboid minor
Which muscles attaching to the transverse processes represent layer two of the true back?
levator scapulae
The trapezius is innervated by what nerve?
the spinal accessory nerve
What forms the spinal accessory nerve innervating the trapezius?
C1-C5 cord levels contribute to the spinal root of the spinal accessory nerve
The latissimus dorsi is innervated by what nerve?
the thoracodorsal nerve
What forms the thoracodorsal nerve innervating the latissimus dorsi?
ventral rami from C6-C8
Which of the muscles of the true back are innervated by the dorsal sacpular nerve?
levator scapulae, rhomboid major, rhomboid minor
What forms the dorsal scapular nerve?
the ventral ramus of C5
The levator scapulae is innervated by what nerves?
the dorsal scapular nerve (ventral ramus of C5) and branches from C3. C4 ventral rami
The rhomboid major is innervated by what nerves?
the dorsal scapular nerve (ventral ramus of C5) and branches from C4 ventral ramus
The rhomboid minor is innervated by what nerves?
the dorsal scapular nerve (ventral ramus of C5) and branches from C4 ventral ramus
What muscles lie beneath the trapezius in the neck?
splenius capitis and splenius cervicis
What does the word “splenius” mean?
it is the greek word for bandage
What part of the vertebra forms the osseous origin for the splenius muscles?
the spinous process
What is the innervation of the splenius capitis?
dorsal rami of middle cervical spinal nerves (C3-C5)
Spenius cervicis will attach to what locations on the spine?
lateral mass of C1 and posterior tubercle of transverse process on C1-C4
What is the innervation of the splenius cervicis?
dorsal rami of lower cervical spinal nerves (C5-C7 cord levels)
Which muscles represent the fourth layer of the true back?
the erector spinae or sacrospinalis muscles
Which muscles are identified as erector spinae or sacrospinalis muscles?
iliocostalis, longissimus, spinalis
What osseous parts of the vertebral column serve as an origin to the iliocostalis lumborum?
spinous processes of T11-T12, L1-L5, median sacral crest, lateral sacral crest
What is the insertion for the iliocostalis lumborum?
costal angles of the lower 6-9 (lol) ribs (rib6-rib12 or rib3-rib12)
What is the innervation of the iliocostalis lumborum?
dorsal rami of lower thoracic and all lumbar spinal nerves
Which subdivision of the iliocostalis muscle appears to have a reversal of origin-insertion?
iliocostalis lumborum pars lumborum
What osseous parts of the vertebral column serve as an origin to the iliocostalis thoracics?
none
What osseous part of the vertebral column serves as an insertion for the iliocostalis thoracis?
transverse process of C7
Which subdivision of the iliocostalis primarily originates and inserts on ribs?
iliocostalis thoracis
What is the innervation of the iliocostalis thoracis?
dorsal rami of upper 6 throacic spinal nerves (T1-T6 cord levels)
What osseous parts of the vertebral column serve as an origin to the iliocostalis cervicis?
none
What is the innervation of the iliocostalis cervicis?
dorsal rami of T1, T2 spinal nerves, sometimes C8 spinal nerve (C8, T1, T2 cord levels)
What osseous parts of the vertebral column serve as an origin to the longissimus thoracis?
accessory process an transverse processes of L1-L5. spinous processes of L3-L5 and median sacral crest S1-S3
Which erector spinae muscle is attached to the accessory process?
longissimus thoracis
What is the inneration of the longissimus thoracis?
dorsal rami of all thoracic and lumbar spinal nerves (cord levels T1-T12, L1-L5)
What osseous parts of the vertebral column serve as an origin to the longissimus thoracis pars lumborum?
accessory process and medial part of transverse process of L1-L5
What is the insertion for the longissimus thoracis pars lumborum?
posterior superior iliac spine (PSIS) of the inominate bone
Which subdivision of the longissimus muscle apppears to have a reversal of origin - insertion?
longissimus thoracis pars lumborum
What is the innervation of the longissimus capitis?
dorsal rami of C1-C3 or C4 spinal nerves, (C1-C3 or C4 cord levels)
Which erector spinae muscles attach to cervical articular processes?
longissimus cervicis and longissimus capitis
What is the innervation of the spinalis thoracis?
dorsal rami of all thoracic and upper lumbar spinal nerves
What is the innervation of the spinalis cervicis?
dorsal rami of all cervical spinal nerves (C1-C8 cord levels)
What is the innervation of the spinalis capitis?
dorsal rami of lower cervical and upper thoracic spinal nerves
Which muscles are identified as trasnversospinalis muscle?
semispinalis, multifidis, and rotators
Based on the name of this group (transversospinalis) what is the origin - insertion of the transversospinalis?
transverse process origin, spinous process insertion
How many vertebrae can be attached to a single segment by transversospinalis muscles?
as many as nine vertebrae
What segment will represent the lowest attachment site for the semispinalis thoracis?
T12
What is the innervation of the semispinalis thoracics?
dorsal rami of T1-T6 spinal nerves (cord levels T1-T6)
What osseous parts of the vertebral column serve as an origin to the semispinalis cervicis?
transverse tubercles of T1-T5 or T6 and articular processes of C4-C7
What is the innervation of the semispinalis cervicis?
dorsal rami of C6-C8 spinal nerves (Cord levels C6-C8)
What osseous parts of the vertebral column serve as an origin to the semispinalis capitis?
transverse tubercles of C7, T1-T6 or T7 and articular processes of C4-C6
What is the innervation of the semispinalis capitis?
dorsal rami of C1-C6 spinal nerves (cord levels C1-C6)
The biventer cervicis is formed by the fusion of what muscles?
semispinalis capitis and spinalis capitis
What regional subdivisions are now identified with multifidis muscles?
lumbar multifidis, thoracic multifidis, and cervical multifidis
Which transversospinalis muscle attaches to articular and mammillary processes along the spine
multifidis
What is the innervation of the classic multifidis?
dorsal rami of C3-C8, T1-T12, L1-L5 and S1 spinal nerves (cord levels C3-C8, T1-T12, L1-L5 and S1)
Contraction of multifidis cervicis will result in what movements?
alters the zygapophyseal capsular ligament response to load distribution
determines the cervical spine response to injury as evidenced by neck pain and is a significant contributor to postural control of the head and neck
Which subdivision of multifidis may demonstrate a reversal of origin - insertion?
multifidis lumoborum
Contraction of multifidis lumborum will result in what movements?
lateral flexion and rotation of the lumbar spine, maintains the lumbar lordotic curve and prevents entrapment of lumbar zygapophyseal capsular ligament during movement
which muscles of the spine exhibit a reversal of the expected origin - insertion?
iliocostalis lumborum par lumborum, longissimus thoracic pars lumborum, and multifidis lumborum
What will replace muscles spanning one or two segmental levels in the cervicals and lumbars?
deep layers of the multifidis
Which suboccipital muscle lacks an attachment to the skull?
obliquus capitis inferior
Which nerve will innervate all suboccipital muscles
the dorsal ramus of C1, the suboccipital nerve
What is the origin of the obliquus capitis inferior?
C2 spinous process and lamina
What is the insertion of the obliquus capitis inferior?
transverse process of C1
Contraction of obliquus capitis inferior will result in what movement?
turns the face to the side
An increase in the density of muscle spindles is most apparent in which suboccipital muscle?
obliquus capitis inferior
Suboccipital muscle feedback relays to what additional locations in the brain?
extraocular nuclei of origin, primary visual cortex and vestibular nuclei
What is the result of communication between suboccipital muscles, visual centers and vestibular centers?
coordination of head and eye position
What is the proposed function of the suboccipital muscle group?
postural stabilizers of the atlanto-occipital and atlanto-axial joints
Which suboccipital muscles are known to attach to dura mater?
rectus capitis posterior major, recuts capitis posterior minor and obliquus capitis inferior
Interspinalis is paired in which regions of the spine?
cervical and lumbar regions
Based on the density of muscle spindles what is the proposed function of the interspinalis?
acts as a proprioceptive transducer in conjunction with intertransversarii to coordinate the smooth movement of the spine and to maintain appropriate posture
INtertransversarii are paired in which region (s) of the spine?
cervical and lumbar regions
Which muscle group is innervated by both dorsal rami and ventral rami of spinal nerves?
intertransversarii
Based on the density of muscle spindles what is the proposed function of the intertransversarii?
acts as a proprioceptive transducer in conjunction with interspinalis to coordinate the smooth movement of the spine and to maintain appropriate posture
What is the origin of the longus colli?
vertebral bodies of C5-C6, T1-T3 and anterior tubercles of transverse processes C3-C5
What will innervate the longus colli?
ventral rami of C2-C6 or C7 spinal nerves
What is the insertion of the longus capitis?
basilar part of the occipital bone
What will innervate the longus capitis?
the ventral rami of C1-C3 spinal nerves
What is the origin of the rectus capitis anterior?
lateral mass and costal element of the transverse process of C1
What will innervate the rectus capitis anterior?
ventral rami of C1-C2 spinal nerves
What is the insertion of the rectus capitis lateralis?
jugular process of the occipital bone
What will innervate the rectus capitis lateralis?
jugular process of the occipital bone
What will innervate the rectus capitis lateralis?
the ventral rami of C1-C2 spinal nerves
What is the insertion of the anterior scalene?
ridge and anterior scalene tubercle of the first rib
What will innervate the anterior scalene?
the ventral rami of C2-C6 spinal nerves
What is the insertion of the middle scalene?
between the tubercle and groove for the subclavian artery on the first rib
Contraction of middle scalene will result in what movements/
laterally flex the neck; elevate the first rib
What will innervate the middle scalene?
the ventral rami of C3-C8 spinal nerves
What will innervate the posterior scalene?
the ventral rami of C6-C8 spinal nerves
The quadratus lumborum is implicated in the formation of which ligament?
the iliolumbar ligament
What osseous part of the vertebral column serves as an origin to the quadratus lumborum?
transverse process of L5
What will innervate the quadratus lumborum?
the ventral rami of T12 and L1-L3 or L4 spinal nerves
What is the origin of the posas major?
vertebral bodies T12, L1-L5, S1 and transverse processes of L1-L5
What will innervate the posas major?
primarily the ventral rami of L2 and L3, may include ventral rami of L1 and L4 spinal nerves
What is the origin of the psoas minor?
vertebral bodies T12, L1
What will innervate the posas minor?
the ventral ramus of L1 spinal nerve
What will innervate the iliacus?
the femoral nerve, primarily the ventral rami of L2 and L3
What will innervate the levator costarum brevis?
the dorsal rami of T1-T12 spinal nerves
What will innervate the levator costarum longus?
the dorsal rami of the lower thoracic spinal nerves
What will innervate the serratus posterior superior?
the ventral rami of T2-T5 spinal nerves…intercostal nerves
What will innervate the serratus posterior inferior?
the ventral rami of T9-T11, the intercostal nerves and the ventral ramus of T12, the subcostal nerve
