Flashcards in Back and Vertebral Column Deck (28):
How many bones make up the vertebral column?
- 7 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 4 coccygeal
Which vertebrae of the vertebral column are fused?
Sacral and coccyx vertebrae
What are the functions of the vertebral column?
• Weight bearing
• Protection of spinal cord, blood vessels and lymphatics
• Site of muscle attachments (allows movement elsewhere)
What features of the vertebral column provide shock absorption?
Describe kyphoses and lordoses
Kyphoses – outwards bending, present in foetus
Lordoses – inwards bend (develop later in development)
Give some examples of lordoses
Cervical and lumbar lordoses
Give some examples of kyphoses
Thoracic and sacral
Name some abnormal curvatures of the back
Excessive thoracic kyphosis
Excessive lumbar lordosis
What type of bones are the vertebrae?
What type of joint is formed by the intervertebral discs?
Each disc forms a fibrocartilaginous joint (a symphysis), to allow slight movement of the vertebrae, and acts as a ligament to hold the vertebrae together.
Describe the structure of an intervertebral disc
2 components: central core of nucleus pulposus with high water content surrounded by layers of fibrocartilage called the annulus fibrosus made up of both type I and type II collagen.
What is spinal disc herniation and what usually causes it?
Spinal disc herniation, also known as a slipped disc, is a medical condition affecting the spine in which a tear in the outer, fibrous ring of an intervertebral disc allows the soft, central portion to bulge out beyond the damaged outer rings, and possibly compress the posterior spinal nerves to cause pain.
Disc herniation is usually due to age-related degeneration of the anulus fibrosus, although trauma, lifting injuries, or straining have been implicated
Where are the tears in the annulus fibrosis that cause disc herniation usually found?
Tears are almost always postero-lateral in nature owing to the presence of the posterior longitudinal ligament in the spinal canal.
What are the three meninges of the spinal cord?
Coverings of the spinal cord
– Dura mater (outside) - durable
– Arachnoid mater - spider legs
– Pia mater (inside)
Briefly describe the movements of the back
Rotation of head and neck and the upper trunk
What type of joints are the facet joints?
Synovial plane (artiulation between vertebrae during movement)
What types of joints are found between the vertebrae and the thoracic vertebrae?
Synovial plane (allows expansion of thorax during inhalation)
What type of joint is found between the skull and the atlas?
Synovial ellipsoid (turning head round)
What type of joint is found between the atlas and axis?
Synovial pivot (nodding)
Describe the posterior longitudinal ligament and its function
Posterior longitudinal – prevents hyperflexion of the back, extends over posterior surfaces of the bodies of vertebrae
Describe the anterior longitudinal ligament and its function
Anterior longitudinal – prevents hyperextension of the back, extends over the anterior surfaces of the bodies of the vertebrae
Describe the ligamentum flavum and its function
Ligamentum flavum - connect the laminae (vertebral arches) of adjacent vertebrae, their elasticity serves to preserve the upright posture, and to assist the vertebral column in resuming it after flexion. The elastin prevents buckling of the ligament into the spinal canal during extension, which would cause canal compression. Main function is to keep column together.
Describe the interspinous ligaments and its function
Interspinous ligaments - thin and membranous ligaments, that connect adjoining spinous processes of the vertebra in the spine, function is to limit flexion of the spine
Describe the supraspinous ligament and its function
Supraspinous ligaments – a ligament found along the vertebral column which connects the tips of the spinous processes facing posteriorly on the body, which also helps to limit hyperflexion.
What are extrinsic back muscles?
All back muscles that are connected to the limbs are called extrinsic muscles, which are superficial (close to the surface) and allow movements of the limbs e.g. shoulders and arms.
What three muscles make up the erector spinae?
There are three intermediate intrinsic back muscles – the iliocostalis, longissimus and spinalis
What do the intrinsic back muscles aid in?
These muscles all aid in extension, controlled flexion and lateral flexion of the back and spine