Please select the eligibility criteria that correspond to the clinical trial below.
Title: Swedish Spinal Stenosis Study. An RCT Comparing Decompression With Fusion to Decompression Only in Lumbar Spinal Stenosis With or Without Degenerative Olisthesis.
Brief Summary: A national randomized multicentre trial (RCT) where decompression is compared with decompression with simultaneous fusion in 245 patients with spinal stenosis on one or two adjacent lumbar levels with or without degenerative olisthesis. The material is stratified for the existence of degenerative olisthesis \>3mm. Monitoring is performed with clinical results from patient surveys after 2 and five years, and with radiological follow-up (MRI, CT and plain X-ray) and an objective function test (6 min walking test) after 2 years. The null hypothesis is that there is no difference in results between the two interventions.


Options:
A: Inclusion Criteria:

* Duration of Symptoms: 12 or more weeks.
* Treatments tried: Nonsteroidal anti-inflammatory medical therapy and physical therapy.
* Surgical Screening: Pain in low back, buttocks, or lower extremity that becomes worse with lumbar extension. Must be confirmed by evidence of central or central-lateral compression of the cauda equina by a degenerative lesion of the facet joint, disc, or ligamentum flavum on MRI, computed tomography scans, or myelograms.
* Tests: MRI to confirm diagnosis and level(s).

Exclusion Criteria:

* Previous lumbar spine surgery.
* Not a surgical candidate for any of these reasons: Overall health that makes spinal surgery too life-threatening to be an appropriate alternative, patient has improved dramatically with conservative care, or the patient is unable (for any reason) to undergo surgery within 6 months.
* Possible pregnancy.
* Active malignancy: Patients with a history of any invasive malignancy (except nonmelanoma skin cancer) are ineligible unless they have been treated with curative intent AND have not had any clinical signs or symptoms of the malignancy for at least 5 years.
* Current fracture, infection, and/or deformity (greater than 15 degrees of lumbar scoliosis, using Cobb measure technique) of the spine.
* Age less than 18 years.
* Cauda equina syndrome or progressive neurologic deficit (usually requiring urgent surgery).
* Unavailability for followup (planning to move, no telephone, etc.) or inability to complete data surveys.
* Symptoms less than 12 weeks.
* Patient currently enrolled in any experimental "spine related" study.
B: Inclusion Criteria:

* Imaging evidence of stenosis
* Unable to walk more than 1/4 of a mile
* No prior surgery for stenosis
* Consents to surgery
* Speaks English

Exclusion Criteria:

* Presence of dementia or organic brain syndrome
* Coronary artery disease, recent myocardial infarction, pulmonary or vascular disease
* Spondylolisthesis (\> 5 mm slippage)
* Severe osteoporosis
* Metastatic cancer
C: Inclusion Criteria:

* Pseudoclaudication in one or both legs and backpain (VAS\>30)
* MRI with 1-2 adjacent stenotic segments (area \<0.75 mm2)between L2 and sacrum
* Duration of symptoms \>6 months
* Informed consent

Exclusion Criteria:

* Spondylolysis
* Degenerative lumbar scoliosis (Cobb angle \>20 deg)
* History of lumbar spinal surgery for spinal stenosis or instability
* Stenosis not caused by degenerative changes
* Stenosis caused by herniated disc
* Other specific spinal conditions, Mb Bechterew, malignancy, neurologic disorders
* History of vertebral compression fractures in affected segments
* Psychological disorders where the surgeon considers participation inappropriate(dementia, drug abuse)
D: N/A

Answer: C