Lumbar spinal stenosis

In one minute

Lumbar spinal stenosis is a narrowing of the canal in the lower back that the nerves run through, caused by wear in the discs, joints and ligaments. It mostly affects older adults and is the commonest reason for spine surgery after 65. The typical complaint is heaviness, aching or tingling in the buttocks and legs that comes on after walking or standing and eases within minutes of sitting or leaning forward; doctors call this neurogenic claudication. MRI (magnetic resonance imaging) shows the narrowing. Between a third and a half of people with mild or moderate symptoms stay stable or improve without surgery, and sudden decline is rare, so treatment starts with exercise and time. When walking distance shrinks enough to limit life, the canal can be reopened through a 7 mm incision.

What it is

The North American Spine Society (NASS) defines degenerative lumbar spinal stenosis as diminished space for the nerves and their blood vessels in the lumbar spine as a result of degenerative change, which when symptomatic produces buttock or leg pain or fatigue, with or without back pain, brought on by walking or standing and relieved by bending forward, sitting or lying down. The narrowing can be central (the main canal), in the lateral recess (the corner where a root turns to leave) or in the foramen (the exit tunnel); the last two are covered on the foraminal stenosis page.

How common it is depends on how it is counted. A 2020 meta-analysis put clinically diagnosed stenosis at about 11% of the general population and 25% to 39% of patients seen for back pain in primary and secondary care, and found radiological narrowing in about 11% of people with no symptoms at all. Regional reports often file it under "остеохондроз" or "стеноз позвоночного канала".

Causes and risk factors

Age is the main one. Discs lose height, the facet joints (the paired hinge joints behind each disc) enlarge with arthritis, and the ligamentum flavum (the yellow ligament lining the back of the canal) thickens and buckles inward. Each change takes a little space; together they take enough. A vertebra that has slipped forward (degenerative spondylolisthesis) narrows the canal further, and a few people are born with a narrow canal that runs out of reserve earlier. In a series cited by NASS, diabetic patients had more complications and less pain relief after decompression. The guideline literature is thin on modifiable risk factors beyond age.

How it develops

Standing upright and walking extend the lumbar spine, which shortens the canal and thickens the ligament; the nerves and their small veins are squeezed. Blood pools, the roots become short of oxygen, and the legs ache, tingle or feel heavy. Bending forward or sitting opens the canal, the veins drain, and the symptom fades within minutes. That is the signature of neurogenic claudication and the reason people with stenosis can cycle for an hour but not walk to the shop. Vascular claudication from narrowed leg arteries also stops people walking, but it settles on standing still and does not care about posture. Rapid or catastrophic neurological decline is, in the words of the NASS work group, exceedingly rare.

Symptoms

NASS suggests the diagnosis in older patients with buttock or leg symptoms brought on by walking or standing that improve on sitting or bending forward, and notes that patients whose pain is not made worse by walking are unlikely to have stenosis. Common details: both legs affected, though unevenly; a wide-based gait; leaning on a shopping trolley for relief; numbness or heaviness rather than sharp pain; leg cramps. Back pain may or may not be present. Sharp pain down one leg with a positive straight leg raise points to a herniated disc instead; pain that does not follow the walking-and-sitting pattern may come from the foramen instead; see the foraminal stenosis page.

Diagnosis

The story is the test. The surgeon asks how far you can walk before the legs give out, what brings relief and whether the symptom is the same every day, then examines strength, sensation, reflexes, gait and balance. NASS suggests MRI as the most appropriate non-invasive test to confirm narrowing or root compression, CT (computed tomography) myelography when MRI is impossible or inconclusive, and plain CT when neither is suitable. It warns that the correlation between how narrow the canal looks and how the patient feels is poorly established, so an MRI report alone never decides treatment.

Report vocabulary: central canal stenosis (mild, moderate or severe), lateral recess stenosis, foraminal stenosis, ligamentum flavum hypertrophy (thickening), facet hypertrophy, dural sac area (the cross-section available for the nerves), and degenerative spondylolisthesis with a grade. Standing X-rays in bending and straightening show whether a slipped vertebra moves, which changes the operation.

If you send us images, photograph the report and the cross-section (axial) images at the narrowest levels, and tell us your walking distance in minutes or metres. That number matters more than the grade in the report.

Treatment without surgery

The honest summary from NASS is that the evidence is thin: physical therapy, medication and manipulation each receive an "insufficient evidence" grade as stand-alone treatments, while a limited course of active physical therapy is endorsed by consensus. A 2021 multidisciplinary guideline is more concrete: it suggests starting with education, lifestyle advice, home exercise, manual therapy and rehabilitation, and recommends against NSAIDs (non-steroidal anti-inflammatory drugs), paracetamol, opioids, muscle relaxants, gabapentin and pregabalin for this condition; all of its recommendations are conditional. Flexion-based exercise and cycling are often advised because they follow the mechanics described above; that is reasoning from anatomy, not trial evidence.

Injections are a middle step. NASS suggests interlaminar epidural steroid injection for relief of two weeks to six months, with conflicting evidence beyond that; the 2021 guideline recommends against epidural steroids on high-quality evidence. Two good sources disagree. A lumbar corset increases walking distance while worn, with no evidence the benefit lasts after removing it.

How often is this enough? NASS says, on weak (grade C) evidence, that non-surgical care can give improvement lasting 2 to 10 years in a large percentage of patients, with 20% to 40% of those followed that long eventually having surgery, and puts the natural course of mild to moderate stenosis as favourable in about one third to one half. The 2016 Cochrane review found no clear benefit of surgery over non-surgical care on low-quality evidence, and noted that 10% to 24% of surgical patients had a complication while the conservative arms reported none.

When surgery is considered

Surgery for stenosis is elective. Because decline is rare, the question is not how narrow the canal is but how much of your life walking has taken away. NASS suggests decompression for moderate to severe symptoms and non-surgical care for mild ones. Progressive weakness, bladder symptoms or a fall from a leg giving way move the decision forward.

The SPORT trial (Spine Patient Outcomes Research Trial) enrolled 654 patients with at least 12 weeks of symptoms. At two years, patients who actually had surgery improved more in pain and function than those who did not, an advantage present by three months. By eight years, the benefit in the randomised group had converged, partly because 52% of the non-surgical arm had crossed over to surgery, while the observational cohort still showed a stable advantage for surgery. Read that as: surgery reliably helps for several years, waiting does not spoil the final outcome, and many who wait end up choosing surgery anyway.

Surgical options

All of them open the canal; they differ in how much they disturb the spine to do it.

• Open laminectomy: the traditional operation, removing the back of the vertebra and the thickened ligament through a midline incision under general anaesthesia. Effective, with more muscle damage and a longer stay.
• Microscopic or tubular decompression: the same result through a smaller opening, often decompressing both sides from one side.
• Full endoscopic decompression (uniportal or biportal; the uniportal PSLD technique, percutaneous stenoscopic lumbar decompression, was developed by our mentor Dr. Kangtaek Lim): the canal is reopened through a 7 mm working channel with a camera. A 2024 meta-analysis of 19 studies and 1,997 patients found less blood loss, hospital stays shorter by about 1.8 days, fewer dural tears and fewer wound infections than microscopic decompression, with comparable pain and function up to two years. See endoscopic lumbar decompression.
• Decompression with fusion: NASS suggests decompression alone for leg-dominant symptoms without instability. When the vertebra is slipping or the joint must be removed to free the nerve, a fusion is added: endoscopic lumbar fusion, or open spinal fusion where the anatomy demands it.
• Interspinous spacers: NASS found insufficient evidence for or against them.

How we treat it at spine.uz

Endoscopic spine surgery in Tashkent for spinal stenosis

Send your MRI and your walking distance on Telegram or WhatsApp. The remote opinion is free; a doctor from the team replies by voice within 48 hours. The in-person consultation and the operation are paid.

When decompression is indicated we do it through a 7 mm incision, most often under local anaesthesia with sedation rather than general anaesthesia; the anaesthetist and surgeon decide per patient. Decompression uses no screws or implants; fusion, when needed, is done endoscopically with a cage and percutaneous screws. Most patients walk on the day of surgery and go home within 24 hours. We operate on all levels, including multilevel cases. We are Tashkent's first endoscopic spine team, five surgeons operating as one team, with 27,600+ endoscopic and spine operations and a complication rate well below 1% in our own series. You leave with a written team conclusion.

Recovery and outcomes

Walking distance is usually the first thing to improve, often within days of decompression, because the mechanical squeeze is gone; numbness and heaviness that were present for years improve more slowly and may not vanish. In a series NASS cites, 79% of patients reported improvement one year after decompression and 66% at a mean of 4.6 years, and the guideline finds that patients aged 75 or older gain the same benefit from decompression as those aged 65 to 74. Complications occurred in 10% to 24% of surgical patients in the trials the Cochrane review pooled; that is the trade-off and belongs in the conversation before the operation. Stenosis can reappear at the same or a neighbouring level years later.

Living with it and prevention

Keep walking within your limit and cycle or swim for fitness; forward-leaning activity is comfortable for a reason. Education, lifestyle advice and a home exercise programme, with manual therapy or rehabilitation alongside, is the package the 2021 guideline supports with moderate-quality evidence; in our experience flexion-based and hip-strength exercises suit the mechanics well. Manage weight, control diabetes, stop smoking. A cane or trolley is not a defeat; it opens the canal. Ask for a review if walking distance falls sharply or a leg starts to give way.