Clinical Perspectives on Lumbar Spinal Stenosis:
Diagnosis, Staging, and the Role of Biportal Endoscopic Decompression

Han-Jin Jang, M.D.

Neurosurgeon, Specialist in Biportal Endoscopic Spine Surgery

Chief of Neurosurgery, New Standard Hospital

Yongin-si, Gyeonggi-do, Republic of Korea

Published: May 2026

Correspondence: hanjinjangspine1.com

Introduction

Lumbar spinal stenosis (LSS) is defined as pathological narrowing of the spinal canal, lateral recesses, or neural foramina, resulting in compression of neural structures and their vascular supply. Unlike acute disc herniation, LSS typically develops insidiously through a complex interplay of degenerative processes: facet joint hypertrophy, ligamentum flavum thickening, loss of disc height, and osteophyte formation.

The condition disproportionately affects persons older than 60 years of age. In Korea, the annual patient burden exceeds 1.7 million, with a marked increase beyond the sixth decade of life. A nationwide cohort study showed that obesity was independently associated with LSS, with a hazard ratio of 1.35 for obesity class I compared with normal weight, suggesting that modifiable metabolic factors contribute to risk in addition to aging.¹

The clinical hallmark is neurogenic claudication — leg pain, heaviness, paresthesia, or weakness that worsens during ambulation or prolonged standing and improves with rest or lumbar flexion. This pattern reflects dynamic changes in the cross-sectional area of the spinal canal, which widens in flexion and narrows in extension.

Differential Diagnosis: LSS versus Lumbar Disc Herniation

Distinguishing LSS from lumbar disc herniation is essential because both may present with radicular leg symptoms but differ in age distribution, provocation pattern, natural history, and treatment strategy.

Table 1. Clinical Differentiation of Lumbar Disc Herniation and Lumbar Spinal Stenosis

The classic “shopping cart sign,” in which walking tolerance improves when a patient leans forward on a cart or walker, reflects flexion-dependent decompression of the stenotic canal and is highly suggestive of LSS. Concurrent disc herniation and stenosis are not uncommon in older patients; diagnosis therefore requires correlation among symptoms, physical findings, and MRI findings.

Clinical Staging and Treatment Algorithm

A practical staging approach can guide treatment discussions by linking symptoms, walking capacity, neurologic findings, and the response to nonoperative care.

Stage 1 — Mild: Conservative Management

Patients have intermittent neurogenic claudication, preserved ambulatory capacity exceeding approximately 500 m, and no objective neurologic deficit. Nonoperative management is appropriate, including anti-inflammatory medication or neuropathic pain medication when indicated, physiotherapy emphasizing flexion-based conditioning and core stabilization, epidural steroid injection for temporary relief, and lifestyle modification.

Stage 2 — Moderate: Reassessment and Escalation

When neurogenic claudication persists beyond 6 to 12 weeks despite conservative treatment, or when maximum walking distance progressively decreases, repeat clinical and imaging evaluation should be considered. At this stage, shared decision-making is important because the stenotic canal generally does not widen spontaneously.

Stage 3 — Severe: Surgical Decompression Indicated

Surgical decompression is generally indicated when maximum walking distance is restricted to less than 100 m, objective lower-extremity weakness is present, or cauda equina syndrome with bladder or bowel dysfunction is suspected. The urgency of treatment increases with neurological severity. A retrospective analysis of Korean National Health Insurance Service data reported a 5-year reoperation rate of 14.2% and a projected 10-year rate of 22.9% after LSS surgery, highlighting the importance of precise initial decompression and appropriate technique selection.²

Biportal Endoscopic Decompression for LSS

Surgical Concept

Biportal endoscopic spine surgery (BESS), also referred to as unilateral biportal endoscopy (UBE), uses two small portals through which a high-definition endoscope and working instruments are introduced independently. Continuous saline irrigation maintains a clear operative field and enables real-time magnified visualization of neural structures.

For LSS, the procedure targets the components responsible for narrowing: hypertrophied ligamentum flavum, medial facet overgrowth, osteophytes, and lateral recess or foraminal encroachment.

Potential Advantages

·         Muscle preservation through avoidance of formal paraspinal muscle detachment.

·         Reduced blood loss and a clearer operative field under continuous irrigation.

·         Earlier mobilization, often within 24 hours after surgery in uncomplicated cases.

·         Shorter hospitalization in selected patients compared with traditional open procedures.

·         Potential suitability for older or medically complex patients when decompression is clearly indicated and perioperative risk is optimized.

Comparative studies have reported that BESS/UBE can achieve decompression outcomes comparable with those of open or microscopic techniques in properly selected patients.^3,4

Patient Selection

BESS/UBE is not universally indicated. Appropriate selection requires concordance between MRI findings and symptoms, assessment of the number of affected levels, evaluation for instability such as clinically meaningful spondylolisthesis, and optimization of medical comorbidities. Surgical planning should be individualized, especially in multilevel stenosis or when fusion may be required.

Non-Surgical Management Strategies

For patients undergoing conservative management or awaiting surgery, practical measures can preserve function and provide objective information about disease progression. Stationary cycling is often better tolerated than upright walking because lumbar flexion transiently increases canal dimensions. Use of a walker or cart may extend functional walking distance by maintaining a flexed posture. Weight reduction may reduce axial loading and is biologically plausible in view of the association between body mass index and LSS risk.¹

Symptom journaling is particularly useful. Recording daily maximum walking distance converts subjective deterioration into a trackable clinical marker and can support timely reassessment.

Special Considerations in Older Adults

Age alone should not be regarded as a contraindication to surgery. Instead, decisions should incorporate frailty, cardiopulmonary reserve, diabetes control, nutritional status, anesthetic risk, and patient goals. In selected older adults, minimally invasive decompression may reduce physiological stress while addressing the structural cause of disability.

Patients and families should also be counseled that neurologic deficit has a better prognosis when decompression is performed before prolonged nerve compression causes irreversible axonal injury.

Conclusion

Lumbar spinal stenosis is a progressive structural disorder requiring stage-appropriate evaluation and treatment. Neither prolonged conservative treatment in the presence of progressive neurologic impairment nor reflexive surgery for mild symptoms serves patients well. The clinician’s task is to characterize disease severity, monitor progression objectively, confirm imaging–symptom concordance, and support shared decision-making.

Biportal endoscopic decompression has emerged as a mature minimally invasive option for selected patients with LSS. Its role will continue to be refined through comparative research, surgical experience, and careful assessment of long-term outcomes. The central message remains that walking disability should not automatically be accepted as inevitable aging; in many patients, it reflects a treatable structural cause.

Disclosures

Conflict-of-interest and funding disclosures should be completed before external submission. This draft was prepared for educational and informational use and does not constitute individualized medical advice.

References

1. Kim JH, Park JH, et al. Association Between Higher Body Mass Index and the Risk of Lumbar Spinal Stenosis in Korean Populations: A Nationwide Cohort Study. Neurospine. 2024;21(4):1142-1151.

2. Ha WJ, Go HY, Ha IH, Lee YJ. Effect of Korean medicine treatment on surgery and opioid prescription among patients with lumbar spinal stenosis: a nationwide retrospective cohort study. Frontiers in Medicine. 2026;13:1703911.

3. Kim HS, Wu PH, Jang IT. Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression Outside-in Approach: Threatening Dural Sac and Ligamentum Flavum Hypertrophy in Lumbar Canal Stenosis. Neurospine. 2021;18(2):418-431.

4. Kang MS, Park HJ, Hwang JH, et al. Biportal Endoscopic Spine Surgery versus Microscopic Tubular Surgery for Single-level Lumbar Spinal Stenosis: A Multicenter, Prospective, Randomized, Parallel-group, Non-inferiority Study. Journal of Korean Neurosurgical Society. 2022;65(4):576-585.

5. Nachemson AL. Disc pressure measurements. Spine. 1981;6(1):93-97.

6. Hansraj KK. Assessment of stresses in the cervical spine caused by posture and position of the head. Surgical Technology International. 2014;25:277-279.

Author note: Han-Jin Jang, M.D., is Chief of Neurosurgery at New Standard Hospital, Yongin-si, Gyeonggi-do, Republic of Korea, and specializes in biportal endoscopic spine surgery.