Back Pain

 

• Differential diagnosis

  Mechanical:

  • Mechanical back pain.
  • Disc herniation: can itself cause pain, or secondarily due to nerve root compression.
  • Trauma

  Bone disease:

  • Ankylosing spondylitis and other inflammatory arthropathies.
  • Osteoporotic vertebral crush.
  • Paget's disease of the bone.
  • Primary or secondary bone cancer; often systemic symptoms too.

  Neurological:

  • Cauda equina syndrome: bilateral leg weakness or pain, incontinent, saddle anaesthesia.
  • Spinal stenosis; may cause claudication.
  • Nerve root compression: unilateral leg neuro symptoms, pain radiates to foot.

• Mechanical back pain

  Definition and epidemiology

  • Back pain in the absence of any obvious pathology such as osteoarthritis or disc prolapse.
  • Onset usually age 20-55 years.
  • Often self-limiting. Only investigate if there are red flags.

  Signs and symptoms

  • Pain in lumbosacral area, buttocks, and/or thighs.
  • Varies with activity and time.
  • Otherwise well.
  • Most episodes resolve in weeks, and 85% within 3 months.

  Psychosocial yellow flags for chronic back pain

  • Believe pain and activity harmful.
  • Low mood.
  • Sickness behaviour e.g. extended rest, social withdrawal.
  • Work dissatisfaction
  • Is seeking compensation.
  • Not engaged in treatment.
  • These also apply to other pain problems which may be functional, such as CFS and fibromyalgia.

  Management

  • Educate about back pain and encourage to stay active and avoid bed rest.
  • Physiotherapy including group exercise programmes, manual therapy (e.g. muscle/joint manipulation, massage).
  • Address psychosocial problems and consider psychotherapy (e.g. CBT).
  • Analgesia: NSAIDs are 1st line but long-term use carries risks. Paracetamol has long been used but is likely ineffective. Further options include weak opioids, while strong opioids should be avoided if possible.

• Back pain red flags

  CT BACK PAIN (actually, get an MRI):

  • Constitutional symptoms, which may point to infection or cancer.
  • Thoracic pain.
  • Bowel or bladder symptoms: cauda equina.
  • Anaesthesia in saddle area: cauda equina.
  • Co-morbidities – cancer, HIV, or steroid use.
  • Klaudication: spinal stenosis.
  • Progressive or constant pain, which may suggest cancer.
  • Age <20 years or >55 years at onset.
  • Insomnia from pain.
  • Neurological symptoms.