PT3 - The Spinal Column

Question 1

What are the key functions of the spinal column?

Answer 1

• communication from brain to limbs via spinal cord
• orientate sense of organs in space
• support viscera + transmit spinal movements to viscera to support health
• resist longitudinal compression due to weight of body + contractions of body/trunk muscles
• facilitate purposeful movement

Question 2

What are the specialisations of the spinal column?

Answer 2

• reinforced by 3 curves; resistance of curved column = 3 squared + 1 (10) => 10 terms straight column
• interdependence => health + function of each curve dependent on curve above/below
• allow centre of gravity to remain balanced
• organs to be appropriately orientated

Question 3

What are the specialisations of the spinal segments?

Answer 3

• combines stability for force transference + mobility for purposeful movement
• resists longitudinal compression: weight of body + contractions of body + trunk muscles
• allow + control amount of movement of one vertebra on another

Question 4

What are the specialisations of the anterior spinal column?

Answer 4

• transmit + a sort forces through disc + vertebral body
• control of compressive forces
• disc influences amount of movement by degree of separation between bodies
• disc influences movement via annular fibres (support facet joints)
• force transference + resistance to compression performed by disc-vertebral body system = fluid nucleus pulposus + cartilaginous annulus fibrosis
• each vertebral body has an end plate (cancellous bone) supporting and supplying fluid to disc cartilage
• periphery of VB => compact + trabecular bone = tensile role

Question 5

Describe adaptations/maladaptations of the anterior column

Answer 5

Adaptation:

• gel portion in centre supported by annulus
• annulus thicker to resist forces
• support of forces through bone structure + curves
• annulus pushes up/down for support
• anterior column well adapted for compressive forces
• resisting forces + nutrition supplied through cartilaginous vertebral end plate

Maladaption:

• delamination => fluid leaks between concentric layers of annulus => nuclear fluid outside annulus
• flexion => posterior disc irritated
• compressive forces downwards => vertebral end plate bony changes
• annulus can bulge into spinal canal causing radiculopathy
• picking up heavy loads can irritate anterior column
• vibration forces can irritate posterior facet joints

Question 6

What are the specialisations of the posterior column?

Answer 6

• allowing + controlling movements (dictated by shape + orientation of facets)
• ligament support + facet capsule = proprioceptive + movement functions
• loading/weight bearing through facet joints

Question 7

What is the base of support?

Answer 7

• whatever is supporting us on earth e.g. feet, buttocks

Question 8

What is the centre of gravity?

Answer 8

• direction of force towards the centre of earth through centre of gravity
• when inside the body = person is stable
• when outside of body = instability <= needs to react to stay balanced
• lies anterior to S2
• changes constantly with body position
• can be located outside body

Question 9

Where does the line of gravity pass?

Answer 9

• external auditory meatus
• Odontoid peg
• bodies of C7, T1 & T2, L3
• sacral promontory
• hip joint
• knee joint
• anterior to malleolus