2.1 Thoracic and Lumbar spinal mechanics Flashcards
Which areas of the spine have lordosis or kyphosis?
lordosis - cervical and lumbar
kyphosis - thoracic and sacral
Describe thoracic vertebra
body: medium size, heart shape, costal facets
spinous process: long, slope postero-inferiorly
Describe lumbar vertebra
body: large and kidney shaped
spinous process: short, broad
What is a vertebral unit?
two adjacent vertebrae and associated intervertebral disc
Where is the pedicle?
between body and transverse process
Where is the lamina?
between transverse process and spinous process
What does the rule of 3 describe?
The location of the spinous process in relation to the transverse process in the thoracic spine
What is the rule of 3?
T1-T3, T12 spinous process located at the level of the transverse process
T4-T6, T11 spinous process is located 1/2 a segment below the corresponding transverse process
T7-T9, T10 spinous process is at the level of the transverse process of the vertebrae one below
What is the superior facet orientation for the cervical, thoracic, and lumbar regions?
cervical: backward, upward, medial (BUM)
thoracic: backward, upward, lateral (BUL)
lumbar: backward, medial (BM)
What are the ligaments of the spine?
Anterior longitudinal ligament Posterior longitudinal ligament Ligamentum flava Interspinous ligaments Intertransverse ligaments
What is the anterior longitudinal ligament?
Strong, broad fibrous band that covers and connects the anterolateral aspects of the vertebral bodies and IV discs
Limits extension
What is the posterior longitudinal ligament?
narrower, somewhat weaker band that runs within the vertebral canal along the posterior aspect of the vertebral bodies
resists hyperflexion
prevents posterior herniation of nucleus pulposus
What is the ligamentum flava?
connects adjoining spinous processes
What are the interspinous ligaments?
connects adjoining spinous processes
What are the intertransverse ligaments?
connects adjoining transverse processes
What does the iliolumbar ligament connect?
ilium to the lumbar vertebrae
What are the transversospinalis muscles?
rotatores, multifidus, and semispinalis
Rotatores breves: origin and insertion, innervation, and action
T1-T12 between transverse and spinous processes of adjacent vertebrae
posterior rami
bilateral: extend thoracic spine
unilateral: rotates thoracic spine to opposite side
Rotatores longi: origin and insertion, innervation, and action
T1-T12 between transverse and spinous processes, skipping one vertebra
posterior rami
bilateral: extend thoracic spine
unilateral: rotates thoracic spine to opposite side
Multifidus: origin and insertion, innervation, and action
sacrum, ilium, mamillary processes of L1-L5, transverse and articular processes of T1-T4, C4-C7
superomedially to spinous processes, skipping 2 to 4 vertebrae
posterior rami
bilateral: extends spine
unilateral: flexes spine to same side, rotates to opposite side
semispinalis capitis: origin and insertion, innervation, and action
C4-T7 transverse and articular processes
Occipital bone between superior and inferior nuchal lines
posterior rami
bilateral: extends thoracic and cervical spines and head (stabilizes craniovertebral joints)
unilateral: bends head, cervical, and thoracic spines to same side, rotates to opposite side
semispinalis cervicis: origin and insertion, innervation, and action
T1-T6 transverse processes
C2-C5 spinous processes
posterior rami
bilateral: extends thoracic and cervical spines and head (stabilizes craniovertebral joints)
unilateral: bends head, cervical, and thoracic spines to same side, rotates to opposite side
semispinalis thoracis: origin and insertion, innervation, and action
T6-T12 transverse processes
C6-T4 spinous processes
posterior rami
bilateral: extends thoracic and cervical spines and head (stabilizes craniovertebral joints)
unilateral: bends head, cervical, and thoracic spines to same side, rotates to opposite side
Degrees for flexion, extension, sidebending, and rotation for entire spine
flexion: 40-90
extension: 20-45
sidebending: 15-30
rotation: 3-8
