Lumbar Fusion
Fusion may be a solution for those who suffer from back pain due to instability of the spine that cause pain. This instability may be caused by a traumatic condition, degeneration of the disc (degenerative disc disease) or other conditions such as spondylolisthesis or joint degeneration. The lower part of the spine, the lumbar, is more likely to be subjected to these conditions because it is the area bearing most weight.
Fusion is a surgical technique performed since the late 1950’s.  Although there are many different techniques to perform it, the objective of fusion is to eliminate motion in the vertebral segment and thus eliminate pain. In the standard procedure, a bone graft is placed between the two vertebrae. This practice speeds up the healing process (similar to a fracture healing), allowing the two vertebrae to grow together (or fuse).
The fusion may also be obtained with the aid of instruments such as cages, plates, screws and rods to keep the spine stable until the actual fusion occurs.
The procedures listed below are the main kind of fusions that can be performed, depending on the patient’s condition and surgeon’s preference.

Postero-lateral fusion
During a postero-lateral fusion your surgeon will approach the spine from your back. In this procedure, the bone graft that allows the vertebrae to fuse together is placed between the transverse processes and the facet joints.
Generally in this procedure the spine is kept stable until the fusion occur using screws and rods.

Surgery: the steps:

1. Your surgeon will approach your spine from the back
2. The lamina is generally removed to relief pressure on the nerve root and the spinal cord
3. Bone graft is placed between the transverse processes and facet joints of the two vertebrae
4. Depending on the conditions, screws may be placed in the vertebra above and below, along with rods.

Posterior lumbar intervertebral fusion (PLIF)
In posterior intervertebral fusion the bone graft is placed in between the two vertebrae, in the space of the intervertebral disc.
The procedure may be performed with the aid of instrumentation that keeps the spine stable until the fusion, or healing process, occurs.

Surgery: the steps:

1. Your surgeon will approach your spine from the back
2. The intervertebral disc is removed
3. The lamina is generally removed on both sides of the vertebra to relief pressure on the nerve root and spinal cord
4. If necessary a little portion of facet joints is removed
5. A cage previously filled with bone graft is inserted in the intervertebral disc space.

Transforaminal Lumbar Intervertebral Fusion (TLIF)
Transforaminal intervertebral fusion is essentially performed like a PLIF , with the difference that less bone is taken off. In fact, one facet join is cleared, while in PLIF a portion of both facet joints are removed. With this approach more space is left for the healing (fusion) process.
The bone graft is placed both in the intervertebral disc space and on the back of the vertebra.

Surgery: the steps:

1. The surgeon will perform an incision on your back
2. The facet joint will be removed
3. The disc will be removed
4. A cage will be filled with bone graft and placed between the vertebrae in the intervertebral disc space. Other bone graft will be placed on the back of the vertebrae.
5. To keep the spine stable until the fusion occurs, screws and rods will be placed on the vertebra above and below.

Anterior Lumbar Interbody Fusion (ALIF)
The anterior lumbar interbody fusion is an anterior approach, which means your surgeon will operate on you through the abdomen.
Due to the approach, this procedure has the advantage that no back muscles or nerves are damaged.

Surgery: the steps:

1. Your surgeon will make an incision on your abdomen which corresponds to the level of the spine that needs to be operated.
2. To reach the spine, the muscles and organs are gently pushed aside
3. The disc is removed
4. One large or two small cages filled with bone graft are inserted in the intervertebral disc’s space
5. The spine is kept stable until the fusion occurs using a plate and screws.