The Vertebral Column As A Region Wk10 Flashcards
What are gross features of the vertebral column?
• Also known as the backbone • Forms the central axis of the skeleton – Main unit of the axial skeleton • Forms the skeleton of the neck • It is around 70-75 cm long • Accounts for 42% of height – (av. UK Height 165-175)
What are gross anatomical features of vertebral column?
- Made from a series of small bones
- Bones are many & close to each other - n=33
- Bones form joints between them
- Bones are strapped together by ligaments
- It Is Therefore:
- Highly Flexible
- Very Strong
Movements of the vertebral column?
Flexion : forwards
Extension : backwards
Abduction : Lateral flexion
Rotation : rotation
What are gross functions of vertebral column?
Provides for: • 1) Centre of gravity of the body (always fall forwards due to being slightly forward of vertebral column) • 2) Attachments for: – Bones – Trunk muscles • 3) Passage of the Spinal Cord • 4) Segmental innervation of the body
The vertebral column in projection of body weight to pelvis
- fall backwards = issues with cerebellum
• The weight of the body is projected into lower limbs about a line that passes centrally through the natural curvatures of the vertebral column
• This line is the centre of gravity of the body - segmental nerves segment from spinal cord
The vertebral column as a site for attachments
• Provides for attachments of the rest of the skeleton (both axial and appendicular)
• Above:
– It bears/supports the head
• Centrally:
– Supports the ribs
– Indirectly supports the upper limbs
• Below:
– Articulates with the hip bones
– Together with the hip bones, they bear most of the body weight.
- Attachment of upper limbs and trunk muscles: the upright posture and therefore support of body weight arises from attachments of trunk muscles to the vertebral column
What can cause abnormalities (e.g. on either side of column)?
Motor tone
What are gross functions of the vertebral column?
• It acts as a conduit through which an assembly of nerve fibres pass:
a) from the brain to the rest of the body (efferents- coming from brain down)
b) from all levels of the body to the brain (afferents- sensory nerve going upwards)
• This neuronal assembly is called the ‘spinal cord’
• The vertebral column covers the spinal cord on its journey
• It allows segmental nerves to leave or join the cord at specified points along the continuum of the vertebral column to supply their targets
What is the vertebral column in the foetus?
• It lies flexed in a single curvature
• The curvature approximates the ‘figure of C’ shape
• The curvature faces anteriorly
– It is concave anteriorly (or an anterior flexion)
• This curvature is known as the “Primary Curvature”
• The primary curvature is retained throughout life in the Thoracic, Sacral and Coccygeal parts
• When exaggerated, the anterior curvature is known as a Kyphosis
What is the vertebral column in young adults?
Viewed from side
Viewed from the side
• It has a more complex presentation
• It has 4 distinct curvatures
• Approximates figure of a stretched “S” •
• It has a sinusoidal profile
• Sinuous bends give the column great flexibility and resilience
• 2 Anterior flexions (anterior concavities)
• 2 Posterior flexions (posterior concavities)
• Anterior Concavities are continuations of the primary curvature of the foetus
• Posterior Concavities are secondary curvatures in response to development
What is the vertebral column in young and young adults?
During development from fétus to young adult
- The primary concave curvature is remodelled in parts
- The C-shaped column opens up to elongate
- It then forms an elongated the figure of S-shape
- This results in the column having both primary and secondary curvatures
- The cervical spine develops the first posterior concavity when a young child begins to lift its head
- This posterior concavity becomes the first secondary curvature
- The lumbar spine also opens up during crawling until the child begins to stand-up and walk
- A second posterior concavity then appears
- This second concavity becomes the second secondary curvature
What are normal curvatures of the vertebral column?
4 curvatures of note: - 2 primary - 2 secondary Top to bottom - Cervical (secondary) - Thoracic (primary) - Lumbar (secondary) - Sacral (primary) • The imaginary line of centre of gravity passes through curvatures of the vertebral column • It is as though the vertebral column wraps itself around this imaginary vertical line
What can go wrong in the vertebral column?
All below have high potential for intervertebral disk herniation
T12 & L1
L5 & S1 - sacrum forms part of pelvic anatomy - much more than compared to lumbar spine (difference between can cause herniations)
- These points constitute natural weak points of the vertebral column
The vertebral column in old age
- Secondary curvatures start to disappear
- The vertebral column seems to return to its original C- shape in the foetus
- A fully continuous primary curvature re- establishes
- The vertebral column closes up again (as if, in the foetus)
What are gross features of the vertebral column?
• It is built from stacking a series of 33 vertebra on top of each other
• 2 assemblies are known:
Discrete Single Vertebrae (separate bones from neighbours - almost stacked on top of each other)
• 24 separable Vertebrae
• All capable of individual movement
Fused Vertebrae (forms a joint)
• 9 vertebrae fuse to give 2 fused bony structures
– Sacrum (fusion of 5 vertebrae)
– Coccyx (fusion of 4 vertabrae)
