What Is Lumbar Spinal Stenosis?
The canal in the spine through which the nerves run can narrow over time as disc height decreases, the facet joints enlarge, the ligament lining the canal (ligamentum flavum) thickens and bony spurs (osteophytes) form. Symptoms appear when the narrowing leaves no room for the nerves. Stenosis may affect a single level or several levels; the most common cause is age-related degenerative change.
The Most Typical Symptom: Leg Pain on Walking
The characteristic picture is neurogenic claudication: pain spreading into the legs, numbness and weakness that begin with standing or walking and ease markedly on sitting or leaning forward (for instance, leaning on a shopping cart). Patients often have to walk for a while and then stop or sit. Advanced cases may have balance problems and, rarely, bladder complaints. This picture must be distinguished from leg pain caused by arterial disease.
How Is It Diagnosed?
Diagnosis starts with history and neurological examination; distinguishing neurogenic claudication from vascular causes is important. The method that best shows canal narrowing and nerve compression is magnetic resonance imaging (MRI). Computed tomography (CT) gives complementary information on bony narrowing and in patients who have had prior surgery. The narrowing on imaging is interpreted together with the patient's symptoms — a 'narrow' image alone is not a reason to operate.
Non-Surgical Treatment First
Initial treatment is conservative, and many patients remain stable this way: regular exercise and physiotherapy, strengthening the trunk muscles, pain management and, in selected cases, epidural injections. The aim is to preserve walking distance and maintain quality of life. This process takes patience and requires regular follow-up; results vary from person to person.
When Is Surgery (Decompression) Considered?
Decompression surgery (laminectomy/laminotomy) is considered for marked walking limitation, progressive muscle weakness or cases that seriously impair quality of life and do not respond to non-surgical care; fusion may be added if there is accompanying instability. In suitable cases, tissue-sparing minimally invasive methods may be used. The aim is to make room for the nerve and reduce leg symptoms. Improvement in walking distance is expected in appropriately selected patients, but no outcome is guaranteed.