Disc herniation

• Pathophysiology:

  • When there is damage to the fibrous outer layer of a disc, the jelly like nucleus pulposus can herniate out and compress surrounding structures leading to myelopathy and/or radiculopathy
  • When this happens there is often inflammation around the area of herniation, further compressing local structures
  • Most commonly occurs around L4,L5 and S1
• Demographics:

  • 30-50 yrs
  • More common in men
• Causes:

  • Most commonly due to general disc deterioration with age, prolapse following straining and twisting
  • Sometimes due to a single excessive injury
  • Certain people seem more vulnerable to prolapse than others so likely a genetic component
• Risk factors:

  • Heavy lifting - occupation or strenuous exercise
  • Sedentary jobs - especially driving
  • Smoking
  • Obesity
  • Increasing age
  • Genetics
• Presentation:

  • Sudden onset severe back pain
  • Pain eased by lying still and worse on movement and straining
  • If there is compression of nerve root - radiculopathy in dermatomal/myotome distribution
  • Common around L4,L5 and S1 = common cause of sciatica
  • If compresses cauda equina this is an emergency
  • Some patients have minor prolapsed disc that does not affect nerves - minimal/no symptoms
• Prognosis:

  • In most cases symptoms improve over a few weeks with conservative management
  • Prolapsed portion of disc regresses over time
• Diagnosis:

  • History and exam - sudden back pain with nerve root symptoms
  • In most cases no tests are needed
  • If imaging needed, MRI is modality of choice
• Management:

  • Red flag symptoms of cauda equina or spinal cord compression = emergency
  • No red flag - STaRT back risk assessment tool
  • If high risk consider group exercise program, manual therapy and/or CBT
  • Keep active - don't do anything that causes excessive pain
  • Apply heat
  • NSAIDs - ibuprofen first line
  • If cant take NSAID consider short term codeine
• Paracetamol alone is not recommended for back pain
• When should patients seek follow up?

  • Symptoms getting worse
  • Get new symptoms
  • Symptoms recur
  • Develop any red flag symptoms
  • Severe pain doesn't subside within 1 week
  • Symptoms persist over 2 weeks
• If symptoms not improving:

  • Reassess to ensure correct diagnosis and rule out red flags
  • Assess adherence to management plan
  • Address psychosocial factors
  • Consider combined physical and psychological programme if not already referred
• When to refer to specialist:

  • Severe radicular pain at 2-6 weeks
  • Significant sciatica pain - consider epidural injection of corticosteroid and local anaesthetic - will allow patient to engage in exercise
  • Surgery if conservative methods not helped and severe symptoms not settled