Spinal Fusion

Overview

Spinal fusion is a surgical procedure that involves placing bone graft material between adjacent vertebrae to promote bone growth that joins together, or “fuses,” the two structures. In patients for whom it’s appropriate, the procedure may be performed using minimally invasive surgical techniques.

Spinal fusion is a surgical technique in which one or more of the vertebrae of the spine are joined together (fused) to stop them from moving against each other. This is done by placing bone grafts or bone graft substitutes between the affected vertebral bone. The graft material acts as a binding medium and also helps to maintain normal disc height – as the body heals, the vertebral bone and bone graft eventually grow together to join the vertebrae and stabilize the spine.

Conditions Treated

There are a number of reasons your surgeon may recommend spinal fusion. This procedure is frequently used to treat:

• One or more fractured (broken) vertebrae
• Spondylolisthesis (slippage of one vertebral bone over another)
• Abnormal curvatures of the spine, such as scoliosis or kyphosis
• Protruding or degenerated discs (the cartilaginous “cushions” between vertebrae
• Instability of the spine (abnormal or excessive motion between two or more vertebrae)

Spinal fusion is typically recommended only after conservative treatment methods fail. Your surgeon will take a number of factors into consideration before making this recommendation, including the condition to be treated, your age, health and lifestyle and your anticipated level of activity following surgery. If you are considering spinal fusion, please discuss this treatment option thoroughly with your spinal care provider.

Patient Experience

During a spinal fusion, the surgeon places a bone graft - generally taken from the patient’s pelvic bone or rib, but sometimes from a bone bank--between two or more vertebrae. Recently the use of BMP (Bone Morphogenic Protein) has reduced the need for bone graft. Over a period of about four to nine months following surgery, your body will produce living bone to replace the bone graft. This new bone will fuse the vertebrae together and they will grow into a single bone. During this period, spinal segments must be held immobile to allow the fusion to complete itself. This immobilization requires the use of either internal instrumentation (plates, wires, rods, hooks, or screws) or external tools (braces or casts). Depending on the type and location of the problem, your sur

Anterior

The surgeon will make an incision in the chest or side and remove inter-vertebral discs in the area of the curve to make the spine more flexible. After placing screws in the vertebrae, the surgeon will connect them using a metal rod. The surgeon will then replace the removed discs with bone graft so that the vertebrae on either side of the graft will fuse together. By tightening down the screws attached to the metal rod, the surgeon will straighten the curve.

Posterior

In performing this procedure, the surgeon will approach the spine through the back. The surgeon will attach anchors to the spine in the form of hooks, screws, or wires. These anchors are then attached to spinal rods that straighten the spine. As in anterior instrumentation, bone grafting fuses all instrumented vertebrae.

Combined Anterior/Posterior Approach

This surgery actually consists of two separate operations--one through the front and the other through the back. Your surgeon may choose to stage the two operations on separate days or perform them together as part of one longer surgery. Compared to a single surgical procedure, staged procedures require one to two additional days in the hospital.

Typical Results

Since spinal fusion joins two or more vertebrae together, many patients raise concerns about a loss of flexibility. Any loss of flexibility depends on the number of vertebrae fused together and their location. Most fusions involve a small number of vertebrae, so the loss of flexibility is minimal. In addition, the reduction of pain often offsets this minor loss of flexibility by allowing most patients to feel even more active. However, even in spinal fusion if pain relief is achieved, patients readily accept the stiffness.