Week 1 - Anatomy of Cervical Spine Flashcards
Describe the anatomy of C0/1
- C1 (known as atlas)
- no body or spinous process
- no disc
- deep articular facets on C1 to allow for sliding for F/E (i.e. nodding)
- very strong ligamentous support
What is the main function of C0/1?
- Flexion and extension (15-20 degree range)
- Lateral flexion is ~3 degrees
- Accounts for 1/3 cervical spine movement in sagittal plane (i.e. flex/ext)
Describe the anatomy of C1/2
- C2 known as axis
- odontoid process/dens is the bony element that projects superiorly
- transverse ligament (atlanto-odontoid stability)
- alar ligaments (upper Cx rotation)
What are the joints in C1/2?
- 2 x atlanto-axial joints
- 1 x atlanto-odontoid joint
Describe the anatomy C2/3
- junction between the upper and lower cervical region
- superior articular processes which are deep and face back and up and medially inclined
- angle of the articular facets is at 40-45 degrees to the horizontal
Describe the motion of the C2/3 segment
- flexion/extension
- coupling rotation and LF (5 deg)
Describe the anatomy of the cervical facets
- facets are oblique antero-posteriorly
- greater angle more proximally - flattens as you go distal ~10 degrees
- freer ROM
- allows F/E and strongly coupled lat/flexion rotation
List the anterior muscles of the upper cervical spine
- longus colli
- longus capitis
- rectus capitis anterior
- rectus capitis lateralis
List the posterior muscles of the upper cervical spine
- rectus capitis posterior major
- rectus capitis posterior minor
- obliquus capitis inferior
- obliquus capitis superior
What are the roles of the upper cervical spine muscles?
They are small/uni-segmental deep little muscles important for:
SPPPC:
- segmental motion control
- posture
- proprioception
- potential pain generators
- connections with visual and vestibular systems
Describe the anatomy of the adult (early 20s) cervical disc
- no gelatinous nucleus
- fibrocartilage + dense fibrous tissue
- nucleus not fully surrounded by the annulus
- no-load relief from the intra-abdominal or intra-thoracic pressure
- disc pressure increases in end-range positions
Describe radiology of cervical disc degeneration
- decreased disc space height
- osteophytes (spurs) mostly anterior
- end-plate sclerosis (end-plate is the top and bottom part of bone that surrounds the disc)
What is the function of cervical facet/zygapophyseal (z) joints?
- guide and restrain movement according to their orientation
- high mechanoreceptor innervation (mechanoreceptors are sensory receptors that responds to mechanical pressure)
- potential pain source (trauma e.g. whiplash)
Describe the anatomy and function of uncovertebral (Luschska’s) joints
- on lower 5 CS vertebral bodies (C3-C7)
- sit laterally
- in front of mixed nerve root and behind vertebral artery/vein
- protect brachial plexus as less LF (lateral flexion)
- guides anterior translation
- Spond
List the anterior muscles in the lower cervical spine
- sternocleidomastoid (SCM)
- infrahyoid
- suprahyoid
List the posterior muscles in the lower cervical spine
- splenius capitis
- splenius cervicis
- semispinalis capitis
- longissimus capitis
- cervical multifidus
What’s the difference between superficial and deep cervical muscles?
- superficial have a greater torque to produce gross cervical movements
- deep has a segmental attachment, large spindle densities and a role in guiding and supporting segmental movement
What is the relationship between cervical spine and thorax?
- sagittal orientation of cervico-thoracic junction dictates angle cervical lordosis
- full excursion of Cx spine dictated by thoracic spine mobility
Describe the motion kinematics of cervical spine (sagittal, horizontal, frontal plane)
Sagittal plane -
- flexion - movement initiated and terminated lower Cx (C4-7)
- C0-4 middle phase and C0-2 extension at EOR flexion
Horizontal and frontal plane (coupled movements lateral flexion and rotation) -
- upper (C0-3) - contralateral LF and rotation coupling
- (C2-3) - variable coupling
- lower (C4-7) - ipsilateral LF and rotational coupling
What is the relationship between cervical spine and shoulder girdle?
- load transfer and protection of neurovascular structures
- levator scapulae active in shoulder elevation - attachment to upper 4 Cx pull posterior to sagittal motion (Cx extension)
