Acute Spinal Cord Compression

Background

• Neurological/oncological emergency
• Often underrecognised due to non-specific symptoms
• Can result in paraplegia

Aetiology

• Can be caused either by a space occupying lesion compressing the spinal cord or injury causing transection of the cord
  • Trauma is the most common cause- high impact C-spine damage
  • Tumours- extradural are usually mets; intradural are normally primaries
  • Infection- abscess (TB/staph most common)
  • Haemorrhage (trauma/bleeding disorders/anticoagulant treatment/ AVMs)
  • Oedema from venous obstruction or ischaemia from arterial obstruction (spinal stroke)
• Aetiology can be classed by site:
  • Vertebral (80%)
    • e.g. trauma; metastatic (bony) disease (most commonly from breast, prostate or bronchial)
  • Meninges (15%)
    • e.g. tumours (meningioma; neurofibroma; ependymoma; lymphoma; metastatic disease; leukaemia); epidural abscess
  • Spinal cord (intramedullary; 5%)
    • Spinal cord tumours e.g. gliomas; ependymoma or metastases

Presentation

• Onset is usually gradual (weeks) but can be acute e.g. in traumatic, metastatic or vascular causes
  • Pain (early)
    • Localised over the spine (this is a common early symptom, particularly in patients with metastatic disease- i.e. DO NOT ignore this in these patients) and/or in a radicular distribution (may be aggravated by coughing, sneezing, straining)
  • Sensory (early)
    • Paraesthesia and numbness which often begins in the lower limbs and spreads up, often to a specific level on the trunk
      • Can be loss of proprioception, light touch or pin-prick sensation
    • Can also cause a reduction in proprioception depending on extent of compression (often later than light sensation; particularly in anterior compression syndromes where the dorsal columns are the last to be affected)
  • Motor (late but common)
    • Weakness or stiffness of the limbs (lower > upper)
      • Weakness may be hard to determine if the patient is not walking prior to symptom onset
      • Can be bilateral or unilateral
  • Sphincters (late)
    • Urgency or hesitancy of micturition, progressing to urinary retention
    • Bowel constipation
• Typically, there are a mixture of upper and lower motor neuron signs
  • Below the level of compression there are usually upper motor neuron signs i.e. brisk reflexes and spasticity
  • At the level of compression there are usually lower motor neuron signs (due to compression of the nerve roots as well as spinal cord) i.e. hyporeflexia and weakness
  • Above the level of compression, signs can be normal

Signs of injury at different spinal levels

• Cervical (above C5)
  • Upper motor neuron signs in all limbs and diaphragmatic weakness (phrenic nerve affected)
• Cervical (at or below C5)
  • Lower motor neuron signs and segmental sensory loss in the arms; upper motor neuron signs in the legs
  • Respiratory (intercostal) weakness
• Thoracic
  • Spastic paraplegia with a sensory level at the trunk
  • Weakness of the legs, sacral loss of sensation and extensor (upward) plantar reflexes

Specific syndromes associated with cord compression (often traumatic/hyperacute causes)

• Cord transection i.e. complete lesion (all motor and sensory modalities affected)
  • Complete loss of motor control and sensation from the anywhere below the level affected
  • Initially a flaccid arreflexic paralysis (spinal shock) with hypotension, bradycardia and hypothermia (classic triad)
    • UMN signs later on
  • Unlikely to recover

• Brown-Sequard Syndrome (Cord hemisection- very rare but produces some classical signs to note; NB can be due to compressive lesions so may present slowly)
  • Disruption of the ipsilateral motor pathways; ipsilateral dorsal column tracts (fine touch/proprioception/reflexes) and contralateral spinothalamic tract

 

*- side of lesion; 1- hypotonic paralysis; 2- spastic paralysis and loss of vibration, proprioception and fine touch; 3- loss of pain/temperature sensation

• Central cord syndrome
  • usually caused by a hyperflexion/hyperextension injury to an already stenotic neck
  • Predominantly distal upper limb weakness; cape-like spinothalamic sensory loss (lower limb power and dorsal column sensation preserved)

NB that weakness is the distal upper limb

Investigations

• Arrange an URGENT MRI (as soon as possible)

Management

• Depends on cause
• Trauma-
  • ABCDE; Immobilise; investigate (X-ray/MRI)
  • Methylprednisolone (Must be given within 8 hours)- Bolus and 24hr infusion
  • Decompress and stabilise
• Tumours
  • Depends on tumour/patient
  • Dexamethasone as soon as possible
    • 16mg IV stat then 4mg PO QDS + PPI cover
    • Reduces vasogenic oedema
  • Radiotherapy or Surgery if clinically suitable
    • Surgery if single level involvement without widespread disease; or radio-resistant disease/previous radiotherapy to the site OR if unknown primary
    • Chemotherapy can only really be considered in rarer highly sensitive tumours
• Infection
  • Surgical drainage
  • Antimicrobial treatment- (High dose IV Ceftriaxone and Metronidazole +/- Flucloxacillin if staph aureus involvement)
• Bleeding
  • Reverse any anticoagulant and surgically decompress