The spine, also called the back bone, is designed to give us stability, smooth movement, as well as providing a corridor of protection for the delicate spinal cord. It is made up of bony segments called vertebrae and fibrous tissue called intervertebral discs. The vertebrae and discs form a column from your head to your pelvis providing symmetry and support to the body. The spinal canal is formed by the placement of single vertebrae, one on top of the other, to form a canal. The purpose of the spinal canal is to create a bony casing from the head to the lower back through which the spinal cord passes.

Spondylolisthesis is a condition in which breakdown of the cartilage between the vertebrae of the spine causes one vertebra to slip out of place on top of the one below it. This causes misalignment and narrowing of the spinal column, a condition called spinal stenosis, which can put pressure on the nerves, resulting in pain in the buttocks or legs with walking or standing. As the spine tries to stabilize itself, the joints between the slipped vertebra and adjacent vertebrae can become enlarged, pinching nerves as they exit the spinal column.

Causes

Spondylolisthesis can be congenital (present at birth) or can develop in childhood or adulthood. The condition generally occurs after age 50 from degenerative (wear and tear) changes from osteoarthritis. It affects six times as many women as men. If spondylolisthesis occurs in the lumbar (lower back) area, the sciatic nerve may be compressed causing sciatica. Sciatica is a painful condition caused by the irritation of the sciatic nerve. The sciatic nerve is the longest nerve in our bodies. It begins in the lower back and extends through the buttocks down the back of each leg to the thighs and feet.

Symptoms

Symptoms of Spondylolisthesis can include:

• Pain in legs or buttocks
• Electrical shock feeling which travels down the leg
• Numbness or tingling in the lower extremities
• Leg muscle weakness

Treatment

Conservative Treatment for Spondylolisthesis may include:

• Rest
• Activity restrictions such as avoiding lifting or bending
• Physiotherapy for range of motion and core strengthening
• Anti-inflammatory medications
• Epidural injections
• Bracing

If symptoms do not improve with conservative treatment options, your surgeon will discuss surgical options with you depending on your particular circumstances.

The goal of the surgery is to remove any abnormal bone that compresses a nerve and to stabilize the spine. Surgery for spondylolisthesis includes:

Decompressive Laminectomy

This is a surgical procedure in which portion of the bone or lamina, causing pressure on the nerves is removed. A surgical incision is made in the back, part of bone and thickened tissue causing pressure on the spinal nerves is removed. This gives more room for the nerves, thus relieving pain and pressure on the nerves. This makes the spine unstable and therefore another procedure, spinal fusion will be performed to stabilize the spine.

Spinal Fusion

It is a surgical technique used to join together two bones in the spine. In spinal fusion, a piece of bone, taken from elsewhere in the body or donated from a bone bank is transplanted between the adjacent vertebrae. As the healing occurs, the bone fuses with the spine. This stimulates growth of solid mass of bone which helps in stabilizing the spine. In some cases, metal implants such as rods, hooks, wires, plates or screws are used to hold the vertebra firm until new bone grows between them.

Risks

Although surgical treatments can be performed to treat spondylolysis they are associated with certain risks and complications. These include:

• Failure to relieve back pain or failure of surgery
• Dislocation of grafts or implants used
• Nerve damage
• Infections
• Blood clots