Spine arthrology (wk10) Flashcards
Identity location of the key spinal ligaments and describe their function:
-Connective tissue, Anterior longitudinal ligament, Interspinous ligament, Superior spinous ligament, Posterior and Anterior longitudinal ligament
-Connective tissue/ soft tissue help to stabilise the spine and the ligaments protect the vertebrae
-Anterior longitudinal ligament -> It stays in front of the vertebrae
-Interspinous ligament -> Broad ligaments between the spinal processes. Support spine shape and help to assist spinal movements.
-Superior spinous ligament -> Tiny ligament found on top of the spinal process. Supports spine shape and help to assist spinal movements.
-Posterior and anterior longitudinal ligament -> Keep the spine in place and keep the intervertebral discs in place
-Ligamenta flava (yellow ligament)
Understand the function of the intervertebral discs:
-Intervertebral discs are another type of important connective tissue for the spine
-The discs are in between 2 vertebrae to support the vertebrae in their own place and helps it to bear weight
-There are also small ligaments attaching to the transverse processes between the 2 vertebrae
-There are more small ligaments inside the transverse processes which keep the spine and vertebrae in place
-This means that we can only move over a certain range in our body because the ligament limit the amount of movement which our body can do
-When we move, our intervertebral disc moves as well with you
Intervertebral disc description of characteristics
-Anulus fibrosis, Nucleus pulposus, Intervertebral foramen
- Anulus fibrosis -> The outer layer has a very strong core. It’s function is to keep the central part, the nucleus pulposus, in place
- Nucleus pulposus -> Material is like sponge/jelly and is good to absorb and distribute weight. This helps the spine to weight bear and distribute the weight evenly into the intervertebral disc. It also absorbs the impact of the force out of the spine.
-Intervertebral foramen -> Tissue around the intervertebral foramen has spinal nerves traveling out of the foramen. The spinal cord is inside the vertebral canal and at each level, is a pair of spinal nerves coming out through the foramen and going into the vein muscles. (Intervertebral foramen is when 2 vertebrae attach together using articular processes and there is then a space between the 2 vertebrae.). When spinal nerves come out of the intervertebral foramen, there is a disc behind it. Behind this, there are ligaments / articular processes that protect the phosphate joint.
Explain symptoms caused by disorders of the intervertebral discs:
-Disc pressure, Degenerated disc, Herniated/ bulging disc
-Disc pressure -> With ageing, the structure becomes less strong and becomes a bit weaker and fragile. This means that the exit of a disc is more likely to happen. This means that the nucleus proposes may exit and then push the annulus fibrosis into a different direction.
-Degenerated disc -> A natural, ageing process where the disk slowly degenerates in the spine. A degenerated disk can become flatter and the annulus fibrosis cannot be kept in place. This reduces the space of the intervertebral foramen which means the spinal nerves can become touched by the bony structure – causing irritation.
-Herniated/ bulging disc -> When there’s an injury to the disc or because of age, the anulus fibrosis becomes less strong. Then when we move and the spine moves, there’s a possibility that the jelly part of the intervertebral disc comes out or changes the shape of the annulus fibrosis which causes the shape to become irregular. The bulging part can then touch the spinal nerve and cause irritation and pain.
Describe the anatomy of the thoracic cage
-The thoracic cage consists of a sternum which is a bony structure which sits at the front of the cage.
-There are 12 pairs of ribs from the thoracic vertebrae attaching to the sternum. Only the first 7 pairs are directly attached, 8 9 and 10 are indirectly attached to the sternum and are attached to the costal cartilage. Ribs 11 and 12 are not attaching to any of the structure and are floating.
-On the back of the rib cage are 12 thoracic vertebrae and on the bottom is a key muscle called the diaphragm.
Function of the thoracic muscles in assisting breathing
-The diaphragm is the key muscle for breathing when the muscle is contracting. When the muscle is contracting, it moves downwards and increases the space of the thoracic cage. It then reduces the pressure inside of the thoracic cage. This then allows the air to automatically go through the nose and fill up the thoracic cage. When the diaphragm is relaxed, then there is a reduced space of the thoracic cage which increases the pressure of it. This pushes the air out through the nose.
-During rest, only the diaphragm is needed for inspiration and expiration. During exercise, the intercostal space muscles are used. The internal intercostal helps to move the rib cage down when contracting. This increases the pressure of the rib cage which then forces the air out. This means when we need to breathe out forcefully, the internal intercostal muscles come in to help. The external intercostals are helping breathe the air in. Meaning that when it contracts, they actually lift the rib cage up, increasing the space of the thoracic cage and allow much more air in the thoracic cage.
Spinal curvature and cervical spine
-Cervical vertebrae
-The cervical region (convex anteriorly) -> 1st cervical vertebra (atlas), 2nd cervical vertebra (axis), 7th cervical vertebra and the vertebra prominens.
-The first 2 cervical vertebrae are known at the atlas and axis and are unique in that their shaped allow for extensive rotary movement to the sides. The relationship between the atlas and the base of the skull allows for significant forward and backward movement.
Spinal curvature and cervical spine
-3 curves and its movable vertebrae
- The primary curve prior to birth and briefly afterwards is C-shaped.
- As muscle development occurs and activity increases, the secondary curves, which are lordotic, develop in the cervical and lumbar regions
- The thoracic curve is concave anteriorly and convex posteriorly, whereas the cervical and lumbar curves are convex anteriorly and concave posteriorly.
- The sacral curve, including the coccyx, is concave anteriorly and convex posteriorly. The normal cirves of the spine enable it to absorb blows and shocks.
Thoracic, lumbar spine and spinal motion
Thoracic, lumbar spine and spinal motion:
-The spinous and transverse processes of the thoracic spine and the posterior ribs are key areas of attachment for the posterior muscles of the spine.
-The thoracic spine is made up of T-2 through T-12 spinous processes
-The lumbar spine is made up of the L-1 spinous process and L2-L5 spinous processes
List the spinal functions
-Weight bear in upright posture
-Act as a shock absorber through the curves and intervertebral discs
-Produce, accumulate and transmit forces through the body
-Be an attachment point for muscles of shoulder and pelvic girdles
-Carry and support the thoracic cage
-Protect the spinal cord
Spinal regions
-Including: 33 vertebrae, spinal curvature, development of curves and increased curves
-33 Vertebrae -> 7 cervical, 12 thoracic, 5 lumbar, 5 sacral (fused), 4 coccygeal (fused) – each region has different functions and attachments
-Spinal curvature -> Thoracic and sacral curves are convex posteriorly – this is called a kyphosis. Cervical and lumbar curves are convex anteriorly – this is called a lordosis.
-Development of curves -> I. Primary curve at birth, ii. Development of secondary cervical curve as a baby learning to sit, iii, Development of secondary lumbar curve as a toddle learning to walk
-Increased curves -> Hypokyphosis and Hyper lordosis. Scoliosis -> An abnormal curve in the frontal plane. Commonly idiopathic and identified in childhood. Can be secondary to other conditions.
Movements at the spine
-Thoracolumbar and cervical movements and where movement occurs
-Thoracolumbar movements -> Flexion/extension, lateral flexion and axial rotation
-Cervical movements -> Flexion/ Extension, Right side flexion/ Left side flexion, Right rotation/ Left rotation
-Where movement occurs -> Cervical spine: flexion/ extension, lateral flexion, rotation. Thoracic spine: rotation, lateral flexion, more limited flexion/ extension. Lumbar spine: flexion/ extension, lateral flexion and more limited rotation
Basics of the vertebrae
-Spinal cord runs along the neural canal
-Bodies separated by intervertebral discs
-Articulations between vertebrae at 2 zygapophyseal joints
-Transverse and spinous processes provide attachments for muscles
-Spinal cord and nerve roots -> Spinal cord passes down the neural canal through the vertebral foramen. Nerve roots leave at each spinal level through the gap posterior to intervertebral disc, between pedicles of vertebrae above and below. There are 31 pairs of spinal roots that can leave the spinal cord.
Structure of the vertebrae
-Cervical and vertebral arteries etc
-Cervical vertebrae -> There are 2 heads on the spinous process due to the differing muscle attachments. The disc is around 45 degrees which allows movements to be easily done. Transverse foramen allow the artery to pass through them which supplies the blood supply to the back part of the brain.
-Vertebral arteries in cervical spine -> Form part of blood supply to the brain alongside internal carotid arteries. Pass through transverse foramen in transverse processes on either side of cervical spine.
* C1 vertebrae – The Atlas. Articulated with the base of the skull at the Atlantooccipital joint. Sits on top of the axis.
* C2 vertebrae – The Axis. Articulates with the atlas at the Atlantoaxial joint. Odontoid process held in place by Transverse ligament. If the ligament snaps then the Odontoid process compresses into the spinal cord and stops you moving and breathing.
-Thoracic vertebrae -> The angle is around 65 degrees of the vertebrae which reduces the movement available. The ribs attach onto the transverse process.
-Lumbar vertebrae -> Much larger body as more weight is going through as it is lower down the spinal cord.
