Cost-effectiveness of Small Size Interarcuair Decompression Versus Extended Decompression in Patients With Intermittent Neurogenic Claudication

Rationale: Minimally invasive techniques have gained popularity to decompress lumbar spinal stenosis in the elderly. However, high quality evidence based on randomised controlled trials are not available.

Objective: To investigate whether small size interarcuair decompression is more effective than conventional laminectomy in patients with intermittent neurogenic claudication caused by lumbar spinal stenosis. Study design: Double-blinded multi-centre randomised controlled trial Study population: In total 236 patients are to be included. The inclusion criteria are: subjects \> 40 years of age with at least 12 weeks of complaints of intermittent neurogenic claudication based on MRI confirmed of LSS, with sufficient knowledge of the Dutch language.

Intervention: Small size interarcuair decompression versus conventional laminectomy.

Main study parameters/endpoints: Primary outcome is the Modified Roland Morris Questionnaire. Secondary outcomes are leg pain, back pain and a 6 minute walk test amongst others.

Nature and extent of the burden and risks associated with participation: based on available literature , it is believed that the risks associated with small size interarcuair decompression are no greater than that associated with a laminectomy, although these will be examined.

Intermittent neurogenic claudication (INC) caused by a lumbar spinal canal stenosis (LSS) is the most frequent reason for spinal surgery in the elderly. Multiple, less invasive surgical techniques are applied without sufficient evidence for benefits for patients or society.

The classic symptoms of INC are leg pain, which can be exacerbated with prolonged walking and standing and/or lumbar extension, and is associated with back pain. Severe stenosis is common in the elderly spine with 30.4% of the population having severe stenosis. However, only 17.5% have complaints of INC.

Conservative treatment, such as physical therapy or pain medication, may give some relief of symptoms. However, surgical treatment is considered to be the gold standard for patients with INC caused by LSS. The first technique ever described to widen the lumbar spinal canal is the wide bony decompression (laminectomy), which is still a widely used technique. However, since INC is often accompanied by back pain, and this to post-operative back pain, it is hypothesized that a wide decompression is a ground for potential instability. Hence, less invasive techniques, such as interarcuair decompression, were developed and implemented.

Recent studies claim that a limited bony decompression is the new 'golden standard' therapy for patients with INC. Limited bony decompression is believed to give less muscle damage and thus a faster postoperative recovery. Furthermore, wide bony decompression (such as a laminectomy) is believed to result in lumbar instability and iatrogenic scoliosis. Performing a procedure with potential more complications in a - generally - elderly population could at least be described as doubtful. The assumption is often made that after a wide decompression recurrence of the complaints must be scarce. However, a (cost-) effectiveness study, which evaluates the effectiveness of small bony decompression compared to a 'classical' extensive bony decompression, has not been performed yet. The opinions on this matter are diverse. A laminectomy involves the removal of more bone and structures at the back of the spine which may result in longer hospitalization and loss of productivity, but it could also lead to spinal instability on the long term. However, the risk of an insufficient decompression may be higher, potentially leading to more reoperations.

By the means of this double-blinded, multi-center randomized controlled trial the investigators will determine the (cost-) effectiveness of a limited bony decompression compared to a wide bony decompression in patients with INC.

Eligibility Criteria:
Inclusion Criteria:

* At least 12 weeks of complaints of INC
* Magnetic resonance imaging showing LSS
* Age \>40 years of age
* Sufficient knowledge of the Dutch language
* Signed informed consent

Exclusion Criteria:

* History of lumbar spine surgery
* \>2 lumbar levels operation or needed discectomy
* Degenerative spondylolisthesis \> grade 1 (on a scale of 1 to 4), scoliosis or disc herniation
* ASA-classification \>3
* Serious psychopathology
* Pregnancy
* Active malignancy
* Plans to move abroad during study period