Intervertebral Disks Flashcards
Function of inter vertebral disks?
Designed for weight-bearing and strength
Act as shock absorbers
What type of joint is the Intervertebral discs ?
Cartilaginous (symphysis)
Name the two main components of the Intervertebral discs
- Annulus fibrosus (outer fibrous part, concentric lamallae of fibrocartilage) 2.Nucleus pulposus (gelatinous central mass)
What makes up the Annulus fibrosus?
Layers of lamallae
cartilagenouse layer criss -crossed
What is the Nucleus pulposus?
gelatinous central mass
How many Intervertebral discsare there?
23-24
How does the Intervertebral discs change as you go down the body?
Increase in size as you go down the back
What is the size of the cervical, thoracic and lumber Intervertebral discs?
3mm in cervical 5mm in thoracic 9-11mm in lumbar
What separates the Intervertebral discs from the bone of the vertebral body?
thin hyaline cartilage layer
What happens to the disk when pressure is applied and removed?
Pressure applied- water squeezed out - disk dehydrated
Pressure removed- water enters-disk rehydrated
Which type of position adds the most pressure to the disk?
Sitting down
What is the optimum position for sitting?
sit and leaan back 110 degrees
Describe the blood supply to the intervertebral disk
Only outer 1/3rd of the disc is vascularised and has nerve supply
How does Nucleus pulposus obtain its nutrients?
Diffusion as it is A vascular. This makes it hard to heal once degeneration beings
Name the joints in the vertebrae and where they are located?
what type of joint is this?
Which movment does it enable?
- Zygapophyseal joints
- Between superior and inferior articular processes of adjacent vertebrae
- Synovial planar joints
Gliding movements
Where do spinal nerves go through
Vertebral foramen
Describe the Anterior longitudinal ligament, its location and function
- Strong broad fibrous band
- Covers and connects anterolateral aspects of the vertebral bodies and IV discs
- Extends from pelvic surface of sacrum to C1 and occipital bone
- Maintains stability of the IV joints limiting extension of vertebral column
Describe the Posterior longitudinal ligament, its location and function
–Narrower weaker band
–Runs within vertebral canal on posterior aspect of vertebral bodies and IV discs
–Attached mainly to IV discs
–Extends from C2 to sacrum
–Helps prevent hyperflexion
–Well innervated
Describe the Ligamentum flavum its location and function
- Extends from inferior border of lamina above to superior border of lamina below adjacent vertebra
- Resists separation of the lamina
- Stops abrupt flexion
- High elastic content so assists with straightening after flexion
Describe the Interspinous ligaments its location and function
•Joins adjacent spinous processes (connects spinous processes)
Also attached to ligamentum flavum anteriouly and supraspinous ligament posteriorly
•Weak; more like a thin membrane
It resists flexion by resisting the separation of the spinous processes
Describe the Supraspinous ligaments
Strong fibrous ligament
Attched to the posterior border (point) of the spinous processes
C7-L3/4 It limits flexion is stronger than the infraspinous ligament
What are the movments of the vertebra
Flextion and extension
Lateral flextion and extension
Rotation
Name two main mucles in the back which attach to the vertebra and what they attach to
Paraspinals- attache to the spinous process
Quadratus Lumborum- Lower back, either side of lumber spine. Attches internally to 12th rib and L1-L4
What is a herniated disk? Name the different stages of its pathological progression
Slipped IV disk
•Contained
Protruding or bulging
•Extruded
Prolapsed or ruptured
•Sequestered
Free fragment
