Lumbar spinal stenosis
Lumbar spinal stenosis is degenerative narrowing of the lumbar spinal canal that compresses the cauda equina and nerve roots, producing bilateral neurogenic claudication that worsens with standing and extension and improves with sitting or forward flexion, diagnosed clinically and confirmed by MRI, managed conservatively first with laminectomy reserved for refractory or progressive disease.
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What this article covers
- Overview
Degenerative narrowing of the lumbar spinal canal that compresses the cauda equina and traversing nerve roots: lumbar spinal stenosis is one of the most common identifiable causes of low back and leg…
- Epidemiology
One of the most common identifiable causes of low back and leg pain in older adults, alongside disc herniation and compression fracture; see low back pain.
- Risk factors
Increasing age, the dominant risk factor, reflecting cumulative facet, ligamentum flavum, and disc degeneration.
- Pathophysiology
Degenerative changes progressively narrow the canal, most commonly from facet osteoarthritic hypertrophy, ligamentum flavum thickening and buckling, and disc bulging, compressing the cauda equina and…
- Clinical features
Neurogenic claudication is the hallmark: bilateral (though often asymmetric) leg discomfort, numbness, tingling, or weakness provoked by standing and walking, absent when seated, and improved by…
- Differential diagnosis
Cauda equina syndrome: bowel/bladder dysfunction, saddle anesthesia, and decreased anal sphincter tone with a rapidly progressive bilateral deficit, unlike the chronic postural pattern of stenosis; a…
- Diagnosis
Lumbar spinal stenosis is a clinical diagnosis established by neurogenic claudication: bilateral leg pain worsened by standing and walking, absent when seated, and relieved by forward flexion, in an…
- Management
First, for mild to moderate symptoms, start an NSAID plus a structured program of abdominal and core muscle strengthening and weight loss when applicable, since core strengthening is specifically…
- Complications
Progressive neurogenic claudication limiting ambulation and function, the most common complication of untreated or undertreated stenosis, with substantial impact on independence in older adults.
- Prognosis
Often a slowly progressive degenerative condition, though the rate varies, and many remain stable for years with conservative management.
- Prevention
Maintain abdominal and core strengthening, specifically recommended for mild-to-moderate stenosis, to reduce symptom burden and delay progression to surgical candidacy.
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