Table 1.

Inclusion and exclusion criteria for the Spinal Stenosis Trial (SST) in the NORDSTEN study

Inclusion criteria

Presence of clinical symptoms of spinal stenosis, such as neurogenic claudication or pain radiating bilaterally to the lower limbs

Non-response to at least 3 months of non-surgical treatment

Radiological findings corresponding to the clinical symptoms of LSS. Central-stenosis or lateral recess-stenosis

Able to give informed consent and to answer the questionnaires

Over 18 years of age

Able to understand Norwegian, both spoken and written

Exclusion criteria

Degenerative lumbar spondylolisthesis, with a slip ≥ 3 mm verified on standing plain x-rays in lateral view

Not willing to give written consent

Previous surgery at the level of stenosis

Fracture or former fusion in the thoraco-lumbar region

Cauda equina syndrome (bowel or bladder dysfunction) or fixed complete motor deficit

ASA-classified 4 or 5

Over 80 years of age

Presence of a lumbosacral scoliosis of more than 20 degrees, verified on AP view

Presence of distinct symptoms in one or both legs, due to other diseases, e.g., polyneuropathy, vascular claudication, or osteoarthritis

LSS at 4 or more levels

Unable to comply fully with the protocol, including treatment, follow-up, or study procedures (psychosocially, mentally, or physically)

The patient is participating in another clinical trial that may interfere with this trial