Spinal Stenosis

Lumbar spinal stenosis is the narrowing of the spinal canal, resulting in compression of the nerves travelling through the lumbar spine into the legs.

Causes:

Degeneration begins in the intervertebral disk where biochemical changes such as cell death and loss of proteoglycans and water content leads to progressive disk collapse. This leads to an increased stress transfer  to the post facet joints, which accelerates
cartilagenous degeneration, hypertrophy and osteophyte formation. This is associated with thickening and buckling of the ligamentum flavum.

The combination of ventral disk bulging, osteophyte formation at the dorsal facet and ligamentum flavum hypertrophy combine to narrow the spinal canal and the space for neural elements.

• Degenrative Spondylolisthesis:

Forward displacement of a proximal vertebrae in relation to its adjacent vertebrae in association with an intact neural arch and in the presence of degenerative changes.

Symptoms:

Due to severe aching pain in the lower back or buttocks that develops

with walking or other activities, pain radiates into one or both legs. Symptoms are relieved by sitting or lying down.

Leg symptoms include: weakness and tingling of legs. The pain radiates down the posterior aspect of the leg to the feet. These symptoms are very similar to the ones found in vascular claudication and it is very important to rule this out when suspecting lumbar spinal stenosis.

Diagnosis:

Stenosis aoccurs as either central stenosis (narrowing of entire canal) or peripheral stenosis (narrowing of the foramen through which the nerve root exits). Severe narrowing of the lateral portion of the canal is called "lateral recess stenosis". Articular facets in the posterior portion of the bony spine thicken and enlarge to cause stenosis.

• MRI:

MRI is a useful way to diagnose Lumbar spinal stenosis.

Management:

Non-operative therapies and laminectomy are the standard treatment of lumbar spinal stenosis.

• Medications: 

Use of medical intervention is poor. Injectable calcitonin may be useful for short term pain relief. Epidural blocks may also transiently decrease pain.

• Surgery:

If no improvement in patients health after 3 to 6 months of conservative treatment then laminectomy is done. Another procedure using interspinous distraction device known as X-STOP was less effective and more expensive when more than one spinal level is repaired.