Prolapsed Disc AND Spinal cord injury Flashcards
The most common vertebral levels affected are [] followed by []
The most common vertebral levels affected are L5/S1 followed by L4/L5
Describe the pathophysiology of a prolapsed disc [3]
Nucleus pulposus losses the mechanical abilities to withstand the pressure and weight of the body.
Annular fibrosis surrounding the nucleus pulposus weakens
A weakening of the posterior longitudinal ligament.
All of the above contributes to the herniation of the nucleus pulposus into the spinal canal.
Describe the clinical features of a prolapsed lower disc
95% of prolapsed disc cases are incidental findings and hence asymptomatic.
Remaining 5%:
* Lower back pain (most common complaint).
* Radiculopathy (dependent on the dermatome).
* Neurological weakness.
* Paraesthesia in the affected dermatome.
* Cauda equina symptoms
NB: The severity of the disease does not correlate with the size of the herniated disc on imaging studies.
[] test: from 30 to 70 degree (known to be the most sensitive examination for lumbar disc herniation, especially nerve root L4-S1). This will reproduce a shooting electrical sensation down the affected dermatome.
Straight leg test positive from 30 to 70 degree (known to be the most sensitive examination for lumbar disc herniation, especially nerve root L4-S1). This will reproduce a shooting electrical sensation down the affected dermatome.
What the is main motion [1] and reflex [1] impacted by an L3 prolapse
What the is main motion [1] and reflex [1] impacted by an L4 prolapse
L3
- Hip adduction
- No reflex affected
L4:
- Knee extension
- Knee jerk affected
What the is main motion [1] and reflex [1] impacted by an L5 prolapse
What the is main motion [1] and reflex [1] impacted by an S1 prolapse
L5:
- Ankle dorsiflexion
- No reflex affected
S1:
Feet plantar flexion
* Achilles relfex affected
Investigation of choice for prolapsed disc? [1]
Magnetic resonance imaging (MRI) scans considered to be the gold-standard due to its high sensitivity in assessing soft tissue pathologies.
Most prolapsed discs are treated conservatively.
In which scenarios would indicate surgery? [3]
What type of surgery is most commonly used? [1]
Cauda equina (emergency referral to a neurosurgeon)
Progressive neurological weakness
Pain lasting > 6 weeks which does not respond to conservative management
Surgery most commonly used:
- laminectomy + micro-discectomy.
Describe the non-surgical treatment of slipped disc [4]
Analgesics (NICE recommend NSAIDs instead of paracetamol as first-line for pain relief)
If radiculopathy is present, NICE recommends the use of the following medications as first-line; amitriptyline, duloxetine, gabapentin or pregabalin.
Corticosteroid epidural injection can be offered in a specialist clinic.
Radiofrequency denervation may be an option in patients with chronic low back pain originating in the facet joints. Radiofrequency is used to target and damage the medial branch nerves that supply sensation to the facet joints associated with the back pain. This is done under a local anaesthetic.
Describe the pathophysiology the primary and secondary mechanism of spinal cord injury
Primary Mechanism of Injury:
- Trauma due to compression, contusion, laceration or transection
- immediate neural cell death in the grey matter and axonal damage in white matter tracts
- vascular damage leading to haemorrhage and disruption of blood-spinal cord barrier.
Secondary Mechanism of Injury:
- Inflammation
- Excitotoxicity results from excessive release and impaired reuptake of glutamate
- Apoptosis is triggered by the activation of caspases leading to programmed cell death. This is further augmented by the release of cytochrome C from damaged mitochondria.
What is the difference between complete and incomplete spinal cord injuries? [1]
Complete spinal cord injury:
- There’s total loss of sensory and motor function below the level of injury.
Incomplete spinal cord injury:
- Some sensory or motor function remains below the level of injury. The degree of function depends on the extent and location of damage.
Describe the clinical features of spinal cord injury
Sudden onset of neurological deficits, primarily motor and sensory dysfunction, which are often associated with pain or discomfort in the back, neck or head
Motor:
* Spasticity: Increased muscle tone leading to stiffness and involuntary spasms.
* Hyperreflexia: Overactive or overresponsive reflexes.
* Babinski sign
Pain
Autonomic Dysregulation:
* Cardiovascular instability: Fluctuations in blood pressure and heart rate due to disruption of sympathetic control.
* Respiratory compromise: Reduced ability to cough or breathe deeply leading to increased risk of respiratory infections.
* Bladder and bowel dysfunction: Incontinence or retention due to loss of voluntary control.
* Sexual dysfunction: Impaired sexual function or fertility issues in both genders.
Spinal shock
Describe what is meant by spinal shock [1]
In the acute phase after injury, a state known as spinal shock may occur. This is characterized by flaccid paralysis, loss of reflexes, and loss of sensation below the level of injury
. It is a temporary condition that lasts from several hours to several weeks post-injury.
Describe what is meant by central cord syndrome [1]
What type of injuries cause this? [1]
Central Cord Syndrome:
- More motor impairment in upper than lower limbs along with variable sensory loss; often seen in elderly patients following hyperextension injuries.
Describe what is meant by Brown-Sequard Syndrome [1]
What type of injuries cause this? [1]
Brown-Sequard Syndrome:
- Ipsilateral motor function loss and contralateral pain/temperature sensation loss; typically caused by penetrating injuries.
Describe what is meant by Anterior Cord Syndrome
[1]
What type of injuries cause this? [1]
Anterior Cord Syndrome:
- Loss of motor function and pain/temperature sensation but preservation of proprioception; usually results from anterior spinal artery occlusion.
