Session 6: Conditions of Cervical and Thoracic Spine Flashcards
What is cervical spondylosis?
A chronic degenerative osteoarthritis affecting the intervertebral joints in the cervical spine.
What is the primary pathology of cervical spondylosis?
Usually it is age-related disc degeneration followed by marginal osteophytosis and facet joint osteoarthritis.
What are consequences of cervical spondylosis?
Narrowing of intervertebral foramina which can put pressure on the spinal nerves leading to radiculopathy.
Symptoms of radiculopathy.
Dermatomal sensory symptoms like pain and paraesthesia.
Myotomal motor weakness.
If the degenerative process leads to narrowing of the spinal canal instead, what can this lead to?
This can put pressure on the spinal cord isntead which leads to myelopathy instead.
Symptoms of myelopathy.
Global muscle weakness, gait dysfunction, loss of blance and/or loss of bowel and bladder control.
What has happened here?
A so called Jeffersson’s fracture where C1 (atlas) has been fractured. There is a fracture of the anterior and posterior arches of the vertebra.
What are the most likely mechanisms of injury of a Jefferson’s fracture?
Axial loading:
Diving into shallow water
Impacting head against roof of a vehicle
Falling from playground equipment
What are the usual complications of a Jefferson’s fracture?
Since the atlas bursts open there likelihood of impingement of the spinal cord is small. This means that this fracture is typically associated with pain but not with neurological signs.
However there may be damage to arteries at base of skull leading to secondary neurological sequalae like ataxia, stroke or Horner’s syndrome.
Symptoms of Horner’s syndrome.
Decreased pupil size
Partial ptosis
Decreased sweating on the affected side of the face
Sunken appearance of the eyeball
How may a patient with Jefferson’s fracture come into the emergency department?
Seemingly ‘with their head in their hands’.
What is this? What is fractured?
This is called a Hangman’s fracture which is a fracture through the pars interarticularis of the C2 vertebra. The x-ray shows spondylolisthesis as well where there has been anterior displacement of C2 on C3.
What is the usual mechanism of injury of a Hangman’s fracture?
Forcible hyperextension of the head on the neck from road traffic collisions.
Is there usually a risk of spinal cord injury in a Hangman’s fracture? Why/Why not?
No there is not. This is beacuse the fracture usually tends to expand the spinal canal so no impingement will follow.
How might you want to diagnose a Jefferson’s fracture?
By X-ray to skull, usually via mouth.
What has happened?
What is called a fracture of the odontoid process or a dens fracture or a peg fracture, they are all the same.
Most common mechanisms of injury of an odontoid fracture?
Flexion or extension injuries.
Most common is hyperextension in elderly patients with osteoporosis falling forwards and hitting their forehead on the pavement without putting their hands forward.
Also hyperflexion can cause odontoid fracture by a blow to the back of the head like falling against a wall.
What is a whiplash injury?
What is the most common mechanism of action?
Forceful hyperexension-hyperflexion injury of the cervical spine.
Patient’s car being struck from the rear leading to an acceleration-deceleration injury. Hyperflexion followed by hyperextension leads to tearing of cervical muscles and ligaments.
What are consequences of whiplash injury?
Tearing of cervical muscles and ligaments.
Can lead to secondary oedema, haemorrhage and inflammation.
Spasms can occur which can result in pain and stiffness.
Patients may also complain of arm pain and paraesthesia.
Lower back pain also develops acutely in 40-50% of patients.
Also chronic myofascial pain syndrome can develop.
What makes the cervical spine so susceptible to whiplash injury?
Because of its high mobility and because the ligaments and joint capsules are weak and loose.
High mobility means low stability.
Give a protective factor against spinal cord injury from whiplash injury.
That the vertebral foramen (spinal canal) is relative large to the diameter of the spinal cord.
Explain cervical intervertebral disc prolapse.
Why would they develop?
Disc herniation where the nucleus pulposus leaks out of the vertebral body through the annulus fibrosus.
This leads to impingement onto an adjacent nerve root or spinal cord.
They can develop spontaneously or due to recent trauma and neck injury.
Symptoms of disc prolapse depend on the site of the prolapse.
What will happen in a paracentral disc prolapse vs. a canal-filling disc prolapse?
In a paracentral disc prolapse it is more likely that a nerve root will become impinged leading to radiculopathy.
In canal-filling disc prolapse the spinal cord will become impinged leading to myelopathy.
In the case of a para-central disc prolapse of C2/C3, which nerve root will become impinged?
In the cervical spine it is always the exiting nerve root that becomes compressed. This means that C3 will become compressed since the cervical nerves exit above their respective vertebrae.
What will a patient with a left-sided C5/C6 prolapse complain of?
C6 compression.
Parasthesia of the left C6 dermatome which would be the radial border of left forearm, thumb and index finger.
Also weakness in left C6 myotome causing weakness in left elbow flexion, supination and wrist extension.
Also pain radiating from C6 aka down the neck and into the skin supplied by the C6 dermatome.
Explain Hoffman’s test.
Patient’s middle finger is held at the middle phalanx and the doctor flicks the finger nail.
In case of no movement of the index finger or thumb after the flick the Hoffman’s sign is negative and therefore normal.
If the index finger or thumb moves in response to the flick that Hoffman’s sign is positive and therefore abnormal.
Remember that this is due to overexaggeration to stimulus, long tracts are supposed to protect against this so long tract damage might be a problem in case the test is postive.
Explain Babinski sign.
Lateral side of the sole of the foot is stroked by a blunt instrument from the heel towards the toes.
Normally in children over the age of 2-3 and adults the response is flexor in that the toes flex downwards towards the sole (plantarflex). This is a negative Babinski sign and it is normal.
In case of a positive Babinski sign the hallux dorsiflexes and the toes fan out. This is abnormal and can suggest damage to the long tracts of the spinal cord.
What has happened?
Spondylolisthesis at C3/C4
+ decompression of spinal cord cervical myelopathy probably as a result of the spondylolisthesis.
What would a metastasis in the T12 vertebra impinging the spinal canal compress?
Why?
The L4-L5 segments of the spinal cord.
Because in the lower thoracic spine and in the lumbar spine the neural segments don’t line up with their respective vertebral segments. This is because the spinal cord is much shorter than the vertebral column.
What is happening here?
What symptoms will possible be present?
Metastasis in the T10 vertebral body compressing the thoracic cord.
T11-12 segments of the spinal cord align with the T10 vertebra so this would lead to pain at the site of lesion, spastic paralysis of all of the muscles in the legs, paraesthesia in the dermatomes distal to the site of cord compression and loss of sphincter control.
Mechanisms of injury to upper brachial plexus.
Excessive increase in angle between the neck and shoulder.
Can occur in trauma or during brith if the shoulders become impacted in the pelvis and excessive traction is applied to the baby’s neck.
What will be the clinical manifestation of upper brachial plexus injury?
Limb hangs by the side in medial rotation with an adducted arm and extended elbow.
This position is called waiter’s tip position and the condition is called Erb’s Palsy
What are the clinical manifestations of Klumpke’s Palsy?
The paralysis affects the intrinsic muscles of the hand and those flexors within the forearm that are supplied by the ulnar nerve
It also affects those muscles supplied by the C8 and T1 fibres within the median and radial nerves. This means that it is not just a straightforward high ulnar nerve injury.
It manifests therefore as a high ulnar claw with hyperextension of all of the metacarpophalangeal joints, flexion of the interphalangeal joints and abduction of the thumb and wasting of the interossei.
Explain winging of the scapula.
How can you examine this?
The medial border of the scapula is no longer held against the chest wall so it protrudes posteriorly.
Ask the patient to place the palm of their hand on a wall and push, if there is long thoracic nerve damage the scapula will lift off from the underlying ribs.
You can also ask the patient to hold their unaffected shoulder with the hand of their affected limb and pull the unaffected shoulder forwards. This places traction on the scapula of the affected limb and elevates it’s medial border.
What is the most common cause of winging of the scapula?
Trauma to the long thoracic nerve.
The long thoracic nerve is vulnerable to surgical trauma during mastectomy with axillary clearance since it passes superficial to the serratus anterior muscle in the medial wall of the axilla and can be stripped along with the axillary nodes and fat.
