Eligibility criteria for the Spinal Stenosis Trial of the NORDSTEN-study.
| Inclusion Criteria |
| 1. Clinical symptoms of lumbar spinal stenosis, neurogenic claudication, or bilateral radiating pain. |
| 2. Not responding to at least 3 mo of nonsurgical treatment. |
| 3. Radiological findings corresponding to the clinical symptoms: central stenosis or lateral recess stenosis. |
| 4. Able to give informed consent and to answer the questionnaires. |
| 5. Age >18 y. |
| 6. Able to understand the Norwegian language, both oral and written. |
| Exclusion Criteria |
| 1. Degenerative lumbar spondylolisthesis with a slip ≥3 mm verified on standing plain x-rays in lateral view. |
| 2. Not willing to participate in the trial. |
| 3. Former surgery in the level of stenosis. |
| 4. Fracture or former fusion in the thoracolumbar region. |
| 5. Age >80 y. |
| 6. ASA classification of 4 or 5. |
| 7. Cauda equina syndrome (bowel or bladder dysfunction) or fixed complete motor deficit. |
| 8. Lumbosacral scoliosis >20°, verified on anteroposterior view. |
| 9. Stenosis in >3 levels. |
| 10. Distinct symptoms in one or both of their legs due to other diseases, such as polyneuropathy, vascular claudication, or osteoarthritis. |
Abbreviation: ASA, American Society of Anesthesiologists.