Myology of the Back Flashcards
What forms the spinal accessory nerve innervating the trapezius?
C1-C5 cord levels contribute tot he spinal root of the spinal accessory nerve
The latissimus dorsi is innervated by what nerve?
Thoracodorsal nerve
What forms the thoracodorsal nerve innervating the latissimus dorsi?
Ventral rami from C6-C8
Which muscles of the true back are innervated by the dorsal scapular nerve?
Levator scapulae
Rhomboid major
Rhomboid minor
What forms the dorsal scapular nerve?
Ventral ramus of C5
What does the word “splenius” mean?
Greek word for bandage
What part of the vertebra forms the osseous origin for the splenius?
Spinous process
Splenius capitis will attach to what locations on the skull?
Mastoid process of temporal bone
Superior nuchal line of the occipital bone
What is the innervation of the splenius capitis?
Dorsal rami of middle cervical spinal nerves (C3-C5 cord levels)
Splenius cervicis will attach to what locations on the spine?
Lateral mass or C1
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 are identified as erector spinae or sacrospinalis muscles?
Ilicostalis
Longissimus
Spinalis
What is the innervation of the iliocostalis lumborum?
Dorsal rami of lower thoracic
All lumbar spinal nerves
What is the insertion for the iliocostalis thoracis?
Costal angles of the upper 6-7 ribs
Transverse process of C7
Which subdivision of the iliocostalis primarily originates & inserts on ribs?
Iliocostalis thoracis
What is the innervation of the iliocostalis thoracis?
Dorsal rami of upper 6 thoracic spinal nerves (T1-T6 cord levels)
What is the origin of the iliocostalis cervicis?
Costal angles of upper 3-6 ribs (ribs 1-3 or 1-6)
What is the insertion for the iliocostalis cervicis?
Posterior tubercle of transverse process of C3, C4-C6
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 & transverse processes of L1-L5
Spinous processes of L3-L5
Median sacral crest S1-S3
What is the innervation of the longissimus thoracis?
Dorsal rami of all thoracic & lumbar spinal nerves (cord levels T1-T12, L1-L5)
What osseous parts of the vertebral column serve as an insertion for the longissimus cervicis?
Posterior tubercle of transverse processes from C2-C6 or C7
Articular processes from C2-C6 or C7
What is the innervation of the longissimus cervicis?
Dorsal rami of C4-C8
T1-T2 spinal nerves (C4-C8 & T1-T2 cord levels)
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
Longissimus capitis
What is the innervation of the spinalis thoracis?
Dorsal rami of all thoracics
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 & upper thoracic spinal nerves
Which muscles are identified as transversospinalis muscels?
Semispinalis
Multifidis
Rotators
Transversospinalis muscles represent what layer of the true back?
5
Based on the name of this group, 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 segments will represent the lowest attachment site for the semispinalis thoracis?
T12
What is the innervation of the semispinalis thoracis?
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
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
Articular processes of C4-C6
What is the innervation of the semispinalis capitis?
Dorsal rami of C1-C6 spinal nerves (cord levels C1-C6)
What osseous parts of the vertebral column serve as an origin to the classic multifidis?
Articular processes of C4-C7
Transverse processes of T1-T12
Mammillary processes of L1-L5
Dorsal surface of S1-S4 or S5
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 zygapophysis capsular ligament response to load distribution
Determines the cervical spine response to injury as evidence by neck pain
Significant contributor to postural control of the head and neck
Contraction of multifidis lumborum will result in what movements?
Lateral flexion & rotation of the lumbar spine
Maintains the lumbar lordotic curve
Prevents entrapment of lumbar zygapophyseal capsular ligament during movement
Which muscles of the spine exhibit a reversal of the expected origin - insertion combination?
iliocostalis lumborum pars lumborum
Longissimus thoracic pars lumborum
Mulifidis lumborum
Which suboccipital muscle lacks an attachment to the skull?
Obliquus capitis inferior
An increase in the density of muscle spindles is most apparent in which suboccipital muscle?
Obliquus capitis inferior
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
Rectus capitis posterior minor
Obliquus capitis inferior
At what locations will interspinalis be absent along the spine?
T3-T4 down to T10-T11
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
Maintain appropriate posture
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
Maintain appropriate posture
What is the origin of the longus colli?
Vertebral bodies of C5-C6, T1-T3 & anterior tubercles of transverse processes C3-C5
Contraction of longus colli will result in what movements?
Flexion and lateral flexion (bending) of the neck
Rotation to the contralateral side
What will innervate the longus colli?
Ventral rami of C2-C6 or C7 spinal nerves
What is the origin of the rectus capitis anterior?
Lateral mass
Costal element of the transverse process of C1
What will innervate the rectus capitis anterior?
Ventral rami of C1-C2 spinal nerves
What will innervate the rectus capitis lateralis?
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?
Ventral ramiof 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
What will innervate the middle scalene?
Ventral rami of C3-C8 spinal nerves
What is the origin of the posterior scalene?
Posterior tubercles of transverse processes C4-C6
What is the insertion of the posterior scalene?
Outer surface of second rib
What will innervate the posterior scalene?
Ventral rami of C6-C8 spinal nerves
Quadratus lumborum is implicated in the formation of which ligament?
Iliolumbar ligament
What is the insertion of the quadratus lumborum?
Transverse tubercle of the transverse process L1-L4
12th rib
What will innervate the quadratus lumborum?
Ventral rami of T12 & L1-L3 or L4 spinal nerves
What is the origin of the psoas major?
Vertebral bodies T12, L1-L5, S1
Transverse processes of L1-L5
What will innervate the psoas major?
Primarily the ventral rami of L2 & L3, may include ventral rami of L1 & L4 spinal nerves
What is the origin of the psoas minor?
Vertebral bodies T12, L1
What will innervate the psoas minor?
Ventral ramus of L1 spinal nerve
What will innervate the iliacus?
Femoral nerve, primarily ventral rami of L2 & L3
What is the origin of the levator costarum brevis?
Transverse tubercles of transverse processes from C7, T1-T11
What will innervate the levator costarum brevis?
Dorsal rami of T1-T12 spinal nerves
What is the origin of the levator costarum longus?
Transverse tubercles of transverse processes from T7-T10
What will innervate the levator costarum longus?
Dorsal rami of the lower thoracic spinal nerves
What will innervate the serratus posterior superior?
Ventral rami of T2-T5 spinal nerves - intercostal nerves
What is the origin of the serratus posterior inferior?
Spinous tubercles of spinous processes from T11, T12, L1 & L2, possibly L3
What will innervate the serratus posterior inferior?
Ventral rami of T9-T11, intercostal nerves
Ventral ramus of T12, subcostal nerve
