Endoscopic lumbar decompression

In one minute

Endoscopic lumbar decompression treats lumbar spinal stenosis (a narrowing of the canal that the nerves run through) by removing the bone and thickened ligament that squeeze them, through a 7 mm incision. It is for legs that ache, cramp or go numb after standing or walking a short distance, when non-surgical care has not helped. No screws or implants are used, and most cases are done under local anaesthesia with sedation. A single level took a mean of 37 minutes in one published series and about 90 in another. Most patients walk the same day and go home within 24 hours.

What the operation is

The canal narrows with age as the facet joints (the paired joints at the back of each vertebra) enlarge, the ligamentum flavum (the ligament lining the back of the canal) thickens and the discs bulge. Decompression removes enough of that material to give the nerves room while leaving the joints and the midline structures that keep the spine stable.

Open laminectomy removes the lamina (the bony roof of the canal) and the spinous process through a midline cut. PSLD (percutaneous stenoscopic lumbar decompression) is the uniportal endoscopic technique developed by Dr. Kangtaek Lim in South Korea, the mentor who trained our team: through one 7 mm port it reaches the central canal and the lateral recess (the gutter where each nerve root runs before it exits), and treats one to three levels through a single skin incision; a paramedian variant (para-PSLD) reaches the foramen. ULBD (unilateral laminotomy for bilateral decompression) is the principle: enter from one side and free both sides. UBE (unilateral biportal endoscopy) uses two small incisions. Removed: the inner lamina, the thickened ligament, the inner edge of the facet, bone spurs, and a synovial cyst or disc fragment if present. Kept: the facet joints, the spinous process and the back muscles, which are parted rather than cut.

Who it is for

The operation is for symptomatic stenosis: neurogenic claudication (leg pain, heaviness or numbness brought on by standing and walking and relieved by sitting or leaning forward) or nerve root pain, with MRI (magnetic resonance imaging) showing narrowing at the matching level, after non-surgical care has failed. The North American Spine Society (NASS) guideline on degenerative lumbar spinal stenosis sets out the questions on which that decision rests.

A narrow canal on MRI is not by itself a reason to operate; severe narrowing is found in people with no symptoms. A small, stable spondylolisthesis (a slip of one vertebra on the next) is not a barrier: in 129 patients treated with endoscopic ULBD, results were excellent or good in 80% without a slip and 77% with one, and segmental motion did not increase. A mobile or higher-grade slip, a deformity that needs correcting, or an unstable segment calls for fusion instead.

How it is done

You lie face down on a frame that flexes the spine. In Dr. Lim's series the anaesthetic was epidural with mask sedation; in a 606-patient series most patients had local anaesthesia. The anaesthetist and surgeon decide per patient.

The 7 mm incision is made beside the spinous process, over the natural fatty plane between it and the multifidus muscle. A dilator and working sleeve are docked on the lamina under X-ray guidance and the endoscope goes through the sleeve under continuous saline flow. The surgeon opens a small window in the lamina, removes the thickened ligament piece by piece, trims the inner edge of the facet until the nerve root on that side is free, then angles the endoscope under the base of the spinous process to free the far side. The endpoint is two nerve roots that move and pulse freely; the incision takes one stitch.

For a single level the mean operating time was 37 minutes in Dr. Lim's 2020 series of 127 patients and about 90 minutes in the 606-patient series. Further levels are reached through the same port; in the 450-case series that described PSLD, one, two and three levels took a mean of 32, 64 and 96 minutes, and the canal area increased by 52% on postoperative MRI with minimal damage to muscle and bone.

Endoscopic compared with open surgery

A 2024 meta-analysis in The Spine Journal pooled 19 studies with 1,997 patients comparing full-endoscopic with microscopic or open decompression: 33 mL less blood loss, a hospital stay 1.8 days shorter, dural tears about a third less often and wound infections about three quarters less often (risk ratios 0.63 and 0.23), and a trend to less pain and better function up to two years that did not reach significance. A 2022 meta-analysis of six randomised trials (646 patients) found fewer complications with the endoscope (risk ratio 0.43), an operation 13 minutes shorter and a leg pain score marginally better.

A 2025 meta-analysis of 11 studies and 1,199 patients compared uniportal with biportal decompression: the biportal operation was about 16 minutes faster and the canal slightly wider afterwards, with a difference in disability score at 12 months of less than one point on a 100-point scale; blood loss, hospital stay, pain, dural tears and complications did not differ. Both are safe; ours is uniportal. One caveat the evidence shares: how often a decompressed segment becomes unstable years later has not been well studied for any technique.

Risks and how we reduce them

• Dural tear, the most frequent complication in the published endoscopic series: 7 of 450 (1.6%) and 5 of 127 (3.9%) in Dr. Lim's series, about 1% across 64,470 lumbar endoscopies in an international surgeon survey, where stenosis decompression carried a higher rate than discectomy, and less frequent than with the microscope in the 2024 meta-analysis. Tears happen where the ligament sticks to the membrane, so in Dr. Lim's technique the ligament is removed in small pieces rather than in one block, and a small tear is sealed during the same operation.
• Epidural haematoma (a blood collection pressing on the nerves): 3.1% in the 2020 series, one needing endoscopic evacuation. In Dr. Lim's published series bleeding points were controlled before the endoscope came out and a small drain was left in every case; a history of bleeding problems and any blood thinners are reviewed before any spine operation.
• Transient nerve root irritation (burning or tingling in the leg): one temporary case among 450 in the 2019 series, and no lasting nerve deficit in either of Dr. Lim's series.
• Incomplete decompression and reoperation: 4 of 450 in the 2019 series needed a repeat endoscopic decompression within six weeks for a missed compression or a haematoma; the single reoperation among 127 in the 2020 series was for a haematoma. In Dr. Lim's protocol the endpoint is two nerve roots that pulse freely, and every patient had an MRI within 24 hours to check the result.
• Infection: one of 450 in the 2019 series and none in the 2020 series; about three quarters less frequent than with the microscope in pooled data.
• Instability later: in the 129-patient series the slip increased in 31% of those who already had one and progressed by more than 5% in 4%, unrelated to outcome. Preserving the facet joint is the first priority of the technique.
• Conversion to open surgery: uncommon in the published series; in the 450-case series two patients (0.4%) went on to an open operation after a dural tear.

Across the team's own operations, complications have been well below 1%. That is our figure, not a comparison with anyone else.

Recovery, week by week

Day 0. Walking once the sedation has worn off. Mean stay was 1.4 days in the 2020 series; most of our patients go home within 24 hours.

Days 1 to 3. Short walks several times a day are the treatment; no lifting.

Week 2. Leg pain and walking distance usually improve first; back soreness from the incision lasts longer. Desk work is often possible.

Week 6. In the 2020 series leg pain had fallen from 7.1 to 3.8 on a 10-point scale by one month. Physiotherapy begins; physical work and sport are discussed at this visit.

Month 3. In the 606-patient series 98% rated their result excellent or good at three months. Numbness improves slowest and may not fully recover when the nerve was compressed for years.

Month 12. In the 2020 series the disability score had fallen by 35 points and leg pain to 2.3 out of 10.

What the evidence says

• Lim and colleagues, Asian Spine Journal 2019: 450 consecutive PSLD cases at one to three levels through a single port; canal area up 52%, pain down 4.0 points, disability down 40%.
• Lim and colleagues, Neurospine 2020: 127 single-level cases; 37 minutes, 1.4 days in hospital, complications 7.1%, results held at 12 months.
• Chin and colleagues, The Spine Journal 2024: 19 studies; less blood loss, shorter stay, fewer dural tears and infections than microscopic decompression, similar pain and function to two years.
• Yang and colleagues, Neurospine 2022: six randomised trials; fewer complications and shorter operations with the endoscope.
• Lobo and colleagues, Global Spine Journal 2025: uniportal and biportal decompression equally safe.

How we do it at spine.uz

We are Tashkent's first endoscopic spine team: five surgeons operating as one team, 27,600+ endoscopic and spine operations in total. Dr. Kangtaek Lim, founder of the uniportal PSLD technique, trained the team; he does not operate in Tashkent. We operate on all levels, including multilevel stenosis; the PSLD technique reaches one to three levels through a single port. The incision is 7 mm, most decompressions are done without general anaesthesia, and no screws or implants are used; where fusion is the right answer we perform it fully endoscopically.

Send your MRI on Telegram or WhatsApp. A doctor from the team replies by voice within 48 hours, free of charge, saying whether decompression is indicated, at how many levels, and whether fusion would be needed. The in-person consultation ends with a written team conclusion, and follow-up continues in the same chat.

Preparing for the operation

Bring the MRI files, a CT (computed tomography) scan if you have one, since it shows the shape of the facets and laminae, standing X-rays, a list of your medicines, and someone to take you home. Tell us about blood thinners, diabetes and heart or lung conditions; the anaesthetist decides what to stop and when to stop eating.