Cervical spine Flashcards
Purpose of the Csp
to orientate the head in space, ensuring the eyes are always level to the horizon.
Overall, the Csp has the greatest ranges of movement, across whole spine.
Factors adding strength and stability to the Csp
- Tubular structure
- Articular pillar
Tubular structure:
- Allows flexibility within multiple vectors of movement
- Small scale – in Blood vessels/Capillaries
- Larger scale – Paraspinal ligaments: Spinous, interspinous, ligamentum flavum, posterior/anterior longitudinal - All combine from sacrum to nuchal line on the occiput, to create a ligamentous tube, supporting the vertebral column. This provides stability and strength to cope with all the forces acting on the Csp.
Articular pillar:
- Modifications of the facets on the pedicles of the vertebra, thicker and wider facets.
- Body – Small Triangular, also has joints of Von Luschka
- Only in Csp to allow extra control of movement and protect the arteries and blood vessels of the Csp.
- Spinous process – C2-3 Bifid, C4-7 long
- Vertebral foramen – small
- TP – Has transverse foramen for veterbral artery,
- Facet Orientation- coronal 45 Deg
- Articular pillar – extension of pedicle
Why is Rheumatoid arthritis a problem for cervical spines?
Overtime 20/30 years repeated episodes of flare ups and inflammation will damage ligaments, they become inflamed and then more and more loose/fragile. Softens and degrades the ligaments – neck instability
Why is Hypermobility spectrum a problem for cervical spines?
– More flexibility than they are meant to have, more movement in the neck. Neck instability.
* Explains why these conditions make Pts prone to headaches and migraines, mobile neck causes issues
Biomechanical mechanisms - levers
1st class lever – fulcrum around occipital-atlanto condyles
Effort - muscles of the neck
Fulcrum - the occiput.
Load - the head
Biomechanical mechanisms - Roll and Slide mechanism
- Concave bone - Atlas facet slides
- Convex bone - Occiptal facet rolls
- Occiput is active moving structure and C1 is passive fixed structure.
- Pivot point around the mastoid process
- Important because the rest of the mechanisms in Csp have a sliding action
- It’s the movement of the occiput on the atlas that produces the rest of the flexion
The significance of the facet orientation
- All movements are driven by the occipital atlantal or the altano-axial joint, the rest of the vertebra in the Csp just follow
- This is dependent on the orientation of the facets as they need to slide on each other in order to allow for this movement.
- Roll and slide happens at OA, other sliding occurs at the rest of the Csp in response to what’s happening at the occiput.
Neurological Spinal Points of Vulnerability
- Spinal cord itself – injury e.g., central disc or cancerous lesion
- Two nerve roots, anterior and posterior, that combine to form the spinal nerve, intervertebral foramen created by junction of two vertebral and where spinal nerves exit, has a fascial sheet over it, any problems e.g., facet capsular inflammation or herniated protruding disc can cause inflammation.