1: Clinical anatomy - spine Flashcards
A vertebra can be split into two distinct areas - what are they called?
Vertebral body
Vertebral arch
Which hole in the vertebra transmits the spinal cord?
Vertebral foramen
What is the function of intervertebral foraminae?
Allow spinal nerves to leave the spinal cord
Which foraminae transmit vertebral arteries?
Transverse foramen
What is C1 called and how is it different from other vertebrae?
Atlas
Two vertebral arches, no body
What is C2 called and how is it different from other vertebrae?
Axis
Odontoid process projecting superiorly
What is C7 called and how is it different from other vertebrae?
Vertebra prominens
Very long spinous process, making it the first palpable cervical vertebra in most people
It has no transverse foramen so doesn’t transmit any vertebral arteries
What type of joint is an intervertebral disc?
Secondary cartilaginous joint
What are the two parts of an intervertebral disc?
Anulus fibrosus
Nucleus pulposus
Intervertebral discs are found between vertebral ___.
bodies
Apart from intervertebral discs, what other joints connect the vertebrae and allow the spine to be flexible?
Facet joints
What movements of the spine do facet joints facilitate?
Flexion
Extension
Lateral flexion
Which region of the spine is most flexible?
Cervical spine
Thoracic bounded by ribs, lumbar has vertically oriented facet joints
What does spondylosis mean?
Generic term meaning degeneration of the spine
Intervertebral discs lose ___ as we age.
What does this lead to?
water
Spondylosis, more specifically osteoarthritis
How may osteoarthritis between two vertebrae be treated?
Fusion
Not the perfect solution as it reduces mobility and OA will continue in other joints
Apart from osteoarthritis, what else may happen to intervertebral discs as they lose water?
Disc prolapse
Herniation of the disc outwards
What is the medical name for a slipped intervertebral disc?
Disc prolapse
Where do most acute disc prolapses occur?
L4/L5 OR L5/S1
What is a common cause of disc prolapse?
Lifting heavy objects
Most acute disc prolapses ___ by themselves.
settle
At which aspect of the spinal cord do
a) motor neurons
b) sensory neurons
originate?
Motor neurons originate anteriorly
Sensory neurons originate posteriorly (dorsally)
How do motor neurons and sensory neurons emerge from the spinal cord?
Motor neurons - ventral root ganglion
Sensory neurons - dorsal root ganglion
Through which holes do the ventral and dorsal root ganglia emerge from the spine?
Intervertebral foramen
What happens to the ventral and dorsal root ganglia as they exit via the intervertebral foramen?
Combine to form SPINAL NERVE
The spinal cord stops at L1. What continues on inferiorly?
Cauda equina
sensory and motor nerve roots running together
The spinal cord ends at __ and the nerve roots continue on as the __ __.
L1
cauda equina
What sac holds motor and nerve fibres together in the spinal cord and cauda equina?
Thecal sac
Nerve roots within the thecal sac are called ___ roots.
Nerve roots emerging from the thecal sac are called ___ roots.
traversing roots
exiting roots
Disc prolapse tends to cause compression of the ___ nerve root.
(traversing / exiting)
traversing
Which traversing nerve root is compressed in a
a) L4/5 prolapse
b) L5/S1 prolapse?
a) L5 traversing root
b) S1 traversing root
i.e always the last one
What is the general name given for a neuropathy occuring at a nerve root (i.e in the spinal cord / cauda equina)?
Radiculopathy
(Latin name for a nerve root is a radix)
Nerve root compression causes pain in which sensory distribution?
Dermatome of that spinal nerve
What condition involves pain caused by radiculopathy of the nerve root supplying the lower leg?
Which nerve roots are compressed?
Sciatica
L4, L5, S1, S2, S3 i.e those supplying the sciatic nerve
What is sciatica?
Radiation of nerve pain along sensory distribution of sciatic nerve i.e the lower leg
What is the name given to the area of muscle supplied by a spinal nerve?
Myotome
What happens to muscle when its spinal nerve roots have been compressed?
What happens in the dermatome?
Weakness in that myotome; absent reflexes
Pain
Apart from disc prolapse, what else may cause compression of nerve roots?
Spinal stenosis
osteophytes and hypertrophied ligaments outside vertebral body
Spinal stenosis causes pain on walking - this is called neurogenic ___.
neurogenic claudication
If a patient experiences back pain when walking uphill, suspect ___.
If it’s experienced when walking downhill, suspect ___.
(disc prolapse / spinal stenosis)
Uphill - prolapse - walking downhill is easier for them
Downhill - stenosis - closed posture, neurogenic claudication
What is the general name for disease involving the spinal cord?
Myelopathy
What is cauda equina syndrome?
What are the symptoms?
Symptoms caused by compression of the cauda equina
Bilateral lower limb weakness
Bladder and bowel dysfunction
Saddle anaesthesia
Loss of anal tone
What symptoms should make you suspect cauda equina syndrome?
Bilateral lower limb motor symptoms
Bladder and bowel dysfunction
Anaesthesia
Loss of anal tone
Which general group of spinal muscles are commonly sprained and strained?
What is their function?
Erector spinae
Maintain posture, lateral flexion
What are some spinal ligaments which contribute to stability?
From posterior to anterior:
Supraspinous ligament
Interspinous ligament
Ligamentum flavum
Posterior longitudinal ligament
Anterior longitudinal ligament
What can still be damaged despite no evidence of bony fractures on a spine X-ray?
Ligaments
Is the spinal cord or cauda equina pierced in a lumbar puncture?
Cauda equina
less chance of puncturing nerves (think putting a needle in spaghetti)
At what level is a lumbar puncture usually carried out?
L3 / L4 or L4 / L5
What can be done surgically for patients with mechanical back pain?
Usually nothing
What are some surgical options for treating sciatica?
Discectomy
Decompression
Which scan is superior to X-rays for diagnosing spinal pathology?
MRI scan
so you can see bone AND soft tissue
What is the bottom of the spinal cord called?
Conus medullaris
