Spine I Flashcards
The spine is composed of 26 vertebrae …
7 cervical, 12 thoracic, 5 lumar, 1 sacrum consisting of 4 fused coccygeal vertebra - all but the sacrum & coccyx = moveable
Average length of male & female spine
male = 71cm, female = 61cm
4 functions of the vertebral column
acts as strong flexible rod with elements that can move forward/back/sideways/rotate, encloses/protects spinal cord, supports head, serves as point of attachment for ribs/pelvic girdle/muscles of back & upper limb
Describe the normal curves of the vertebrae column
if viewed laterally then it’ll have 4 slight bends, relative to the front of the body - cervical and lumbar = convex whilst thoracic and sacral = concave
Purpose of the curves - 4 points
increase strength, helps maintain balance in upright position, absorb shocks during walking, help protect vertebrae from fracture
Scoliosis
lateral bending of the vertebral column (usually thoracic region), most common, uneven shoulders/waist, 1 shoulder blade more prominent, 1 hip higher and a lean to one side, can cause chronic back pain & arthritis, treatment = back brace/physiotherapy/surgery
Kyphosis
Increase in thoracic curve, particularly in elderly because its a degeneration of intervertebral discs, also caused by rickets/TB of spine/poor posture, common in females with advanced osteoporosis
Lordosis
Increase in lumbar curve, can occur from increased weight of abdomen (e.g. pregnancy/extreme obesity/poor posture/rickets/osteoporosis/TB of spine)
Describe Intervertebral Discs - description and function - 3 points
found between the bodies of adjacent vertebrae from the second cervical vertebrae to the sacrum, each disc has an inner part and an outer ring, they form strong joints allowing various movements of the vertebral column and absorb vertical shock
Annulus Fibrosus
an outer fibrous ring in an intervertebral disc consisting of fibrocartliage
Nucleus Pulposus
an inner soft, pulpy, highly elastic substance in an intervertebral disc
Describe what happens to the intervertebral discs when they’re under compression, during the day and during the night, and with age
under compression they flatten/broaden, during the day the discs are compressed so you become shorter throughout the day but then at night there is less compression so you’re therefore taller in the morning, with age the nucleus pulposus hardens and becomes less elastic and therefore causes a narrowing of the discs and compression of the vertebrae hence decreasing height with age
Describe a herniated (slipped) disk - 3 points
the intervertebral discs are constantly being compressed because they’re shock absorbers and this pressure could cause the nucleus pulposus to herniate (protrude) posteriorly or into an adjacent vertebral body - common in lumbar region, often slips posteriorly towards spinal cord/nerves - acute pain and treatment = bed rest/painkillers/physio/surgical intervention (laminectomy) - part of laminae of vertebrae or intervertebral disc removed to relieve pressure on nerves
Describe what a vertebra typically consists of
body, vertebral arch, several processes
Describe the typical body of a vertebra
thick, disc-shaped anterior portion is the weight-bearing part, roughened superior & inferior surfaces for attachment of intervertebral discs, anterior & lateral surfaces have nutrient foramina which are opening allowing blood vessels to supply nutrients & O2 and take away CO2 & waste
Describe the typical vertebral arch of a vertebra
2 short, thick processes called pedicles which project posteriorly from the vertebral body, they join flat laminae to form a vertebral arch extending posteriorly, the body of the vertebra and the vertebral arch surround the spinal cord forming a vertebral foramen to contain it
Vertebral (spinal) canal
what all the vertebral foramina collectively form to contain the spinal cord
Describe the vertebral notches - 3 points
pedicles have a superior and inferior vertebral notch which when the vertebrae are stacked on top of each other creates an opening between the adjacent vertebrae called the intervertebral foramen of which a single spinal nerve passes through to a specific region of the body
Describe the transverse and spinous processes of a vertebrae
The transverse processes arise where the lamina and the pedicle meet, extending laterally on each side, a single spinous process projects posteriorly form the junction of the laminae - all attachment points for muscles
7 processes aries from the vertebral arch …
2 transverse, 1 spinous, 2 superior articular, 2 inferior articular
Describe the articulations of the superior and inferior articular processes of the vertebrae
The 2 superior articular processes of a vertebra articulate with the 2 inferior articular processes of the vertebra immediately above it, hence the 2 inferior articular processes of a vertebra articulate with the 2 superior articular process of the vertebra directly below it and so on
The articulating surfaces of the articular processes are …
facets
Intervertebral/facet joints
articulations formed between the bodies and the articular facets of successive vertebrae
