Pathophysiology

  • Narrowing of the spinal canal secondary to degenerative changes in the lower back including bulging of discs, thickening of ligaments
  • Narrowing results in compression of the spinal nerves or spinal cord (myelopathy), and of the blood vessels supplying to the nerves 

Clinical Features

  • Bilateral back, buttock/thigh/leg pain, with associated numbness, tingling, weakness 
  • Symptoms are exacerbated when walking/ exertion, or prolonged standing - claudication. 
  • Symptoms are exacerbated by back extension, and relieved by flexion which increases the canal space - trolley cart sign.
  • Symptoms are relieved by rest, or sitting down/leaning forwards 

Investigations

  • 1st line: MRI
Figure 217: Lumbar MRI showing spinal stenosis in a 71 year old man, severely affecting L4-L5 and moderately affecting L2-L3 and L3-L4. The stenosis is caused  by spondylosis with degenerative discopathy and posterior arthropathy. Attribution: Jmarchn, CC BY-SA 3.0 .

Management

Management should be individualised based on symptom severity, patient comorbidities, and response to conservative therapies.

  • Conservative Treatments:
    • Physical therapy: Strengthening and flexibility exercises to relieve pressure on the spine.
    • Pain relief: Nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol etc. 
    • Epidural steroid injections: To reduce inflammation and pain.
  • Surgical Treatments:
    • Decompression surgery: Laminectomy or laminotomy to relieve pressure on spinal nerves.
    • Spinal fusion: In cases of instability or spondylolisthesis, fusion may be performed to stabilise the spine.
    • Minimally invasive procedures: Options like interspinous process devices to open up the spinal canal may be considered.