Lumbar spinal stenosis refers to the narrowing of the spinal canal and /or the vertebral foramina in the lower back. This causes compression of the spinal cord (lumbar central canal stenosis) and of the spinal nerves (lumbar foraminal stenosis) passing through the vertebral foramina.
Lumbar spinal stenosis usually occurs due to osteoarthritis and the degenerative changes in the spine as a part of the natural ageing process. It is more common in adults after the age of 50 years. However, in some patients, a narrower spinal canal may be present at birth (Congenital spinal stenosis). In others, it can result from the degenerative changes of a previous lower back injury.
Degenerative changes in the spine result in:
- Decreased height of disc space
- Herniated or bulging disc
- Collapse of disc space
- Bony outgrowth (osteophytes)
- Thickening of ligaments around the spine (especially spinal ligament, ligamentum flavum)
The common symptoms of lumbar stenosis include:
- Back pain
- Pain, numbness or tingling sensation in buttocks or legs
- Weakness in the legs
- Difficulty in movement
- Sitting or leaning forward reduces pain
It is a progressive condition and in severe cases it may cause bladder and bowel dysfunction or paralysis of the lower limbs (paraplegia).
Detailed medical history coupled with physical and neurological examination is essential for an accurate diagnosis. Neurological examination involves the evaluation of reflexes and muscle weakness and helps in identification of any injury. Your doctor may also order an X-ray, MRI or CT for the confirmation of the diagnosis. A myelogram may also be ordered for a better visualization of the compression of the nerves.
Non-surgical treatment is preferred approach and includes pain medication such as non-steroidal anti-inflammatory drugs, muscle relaxants and spinal injections. Back braces may also recommended for a few days, to keep the lower back still and reduce mechanical pain due to movement. Physical therapy, non-surgical spinal decompression or acupuncture may be helpful in some cases.
Surgery is considered in patients with intolerable pain, spinal instability and neurologic dysfunction. The two commonly performed surgical procedures for treatment of lumbar spinal stenosis are laminectomy and spinal fusion.
Laminectomyinvolves increasing the space around the spinal cord and /or nerve by removing bone, bone spurs and ligaments compressing them. It is done either by an open surgery or a minimally invasive approach. In patients with spinal instability due to arthritis, spinal fusion may also be coupled with laminectomy. Spinal fusion involves permanent fusion of two vertebrae with rods and screws to eliminate the movement between them.
Most patients undergoing surgery find significant respite in pain post-surgery.
Consult your surgeon to clarify any concerns you have about the surgery