Caused by degenerative narrowing of the spinal canal, commonly at L4/L5
Presents with bilateral leg pain, claudication, and neurological symptoms
Worse with extension/standing, relieved by flexion/sitting (trolley sign)
MRI is the investigation of choice
Manage conservatively or with decompression surgery if severe
🧬 Pathophysiology
Degenerative narrowing of the spinal canal, often due to:
Disc bulging
Facet joint osteoarthritis
Ligamentum flavum hypertrophy
Leads to compression of spinal nerves and vessels → neurogenic claudication ± myelopathy
👀 Clinical Features
Bilateral pain: lower back, buttocks, thighs or legs
Neurogenic claudication: pain, numbness, tingling, or weakness in legs when walking/standing
Relieved by flexion (e.g. leaning forward on trolley – trolley sign)
Worse on extension (e.g. walking upright or standing for long)
🧪 Investigations
MRI lumbar spine – 1st line
Shows canal narrowing and nerve root compression
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
Conservative
Physiotherapy – posture and core-strengthening exercises
Pain relief – NSAIDs, paracetamol
Epidural steroid injections – reduce inflammation
Surgical
Decompression (laminectomy or laminotomy) – 1st line if conservative fails
Spinal fusion – if instability present (e.g. spondylolisthesis)
Minimally invasive techniques – e.g. interspinous process spacers
📝 Exam Clues & Clinchers
Back + bilateral leg pain on walking, relieved by flexion/sitting → spinalstenosis
