L20 spinal column - ligaments and muscles Flashcards
what are the 2 types of joints of the vertebral column?
- IV joint & disks
- facet joints
Describe IV discs
ie function and structure
- the IV discs are designed for** weight bearing and strength and therefore increase in size as the vertebral column descends **
- each IV disc contains a** thick outer ring of fibrous cartilage** called the anulus fibrosus and an** inner gelatinous core** called the **nucleus pulposus **
Describe facet joints
where are they formed? what kind of movements do they provide?
- formed between the** superior and inferior articular processes** of adjoining vertebrae
- the articular surface of each facet is lined with hyaline cartilage
- they permit gliding movement - however the type depends on the region of the vertebral column.. but may be flexion, rotation, extension etc
where does movement of the spine occur & how does this movement occur?
- movement takes place at the joints
- by the contraction / relaxation of the muscle bellies anchored to the spine via their tendons
what is a ligament?
a band of tough elastic tissue that connects bones to other bones to forma joint
what are the 7 key ligaments of the spine?
- anterior longitudinal ligament (ALL)
- **posterior longitudinal ligament **
- ligamentum nuchae of C spine
- **Supraspinous ligament **of T&L spine
- Interspinous ligament
- intertransverse ligament
- ligamentum flavum
Describe the anterior longitudinal ligament
- the anterolateral surface of the vertebral bodies and IV discs are covered by a strong fibrous tissue called the ALL
- goes from C2 to pelvic surface of sacrum
- contains a superficial and deep part
- critical for stability
what is the crucial function of the anterior longitudinal ligament?
- stability
- prevents anterolateral herniation of IV discs and hyper extension of spine
Describe the **posterior longitudinal ligament **
- this ligament runs **along the posterior surface of the vertebral bodies **
- goes from C2-sacrum
* much narrower than the ALL - it functions to resist hyperflexion of the vertebral column and** prevents posterior herniation **
what does the posterior longitudinal ligament extend into the intracranial aspect of the base of the skull?
- the tectorial membrane
Describe the nuchal ligament
structure
- The nuchal ligament is a thick fibroelastic band **at the back of the neck **that extends between the base of the skull and C7 in the midline
- attaches at the external occipital protuberance to the posterior border of the foramen magnum
what is the** function of the nuchal ligament**?
- support the head
- prevents excessive forward flexion
in the thoracic and lumbar regions of the spine, what is the extension of the ‘nuchal’ ligament called?
what is it and function…
- supraspinous ligament
- functions to prevent excessive forward flexion
Describe the interspinous ligament
- the interspinous ligaments connect the adjacent vertebral spinous processes
- weak
- most developed in the lumbar region
what is the** function of the interspinous ligament **?
- limits and** prevents excessive forward flexion and rotation **