Lumbar Fusion Treatment
When patients have chronic pain in the low back and other treatment options have been ruled out, a lumbar fusion surgery may be necessary. The procedure encourages the formation of a union between two or more vertebrae in the lower portion of the spine. Besides reducing back pain, a successful procedure can immobilize the spine and reduce abnormalities that have developed in its curvature.
A spinal fusion is a union of two or more vertebral bodies due to new bone growing together between them. The process is hastened with the use of graft materials, which have the role of giving structural support across the disc space, or interbody space, between two vertebral bodies. The spine can therefore be stabilized in that location.
Numerous materials can promote proper fusion. The patient’s own bone, donated from another portion of the patient’s skeleton, was the material of choice in the earlier days of this procedure. New materials that have been developed over the past 10 years have allowed for an expansion of options and more independence from the need for the patient’s bone.
Further immobilization can be achieved through the application of surgical implants in the spine. The increased support increases the chances of a successful and clean fusion over the course of the next 6 to 12 months.
Reasons to Have the Spinal Lumbar Fusion Surgery
The lumbar fusion surgery can lead to a decrease in back pain, as well as immobilization of the spine and an improvement in the curvature of the spine. The affected area and pain are in the low back, or lumbar level.
The spinal lumbar fusion surgery can become a necessity as the result of other treatments, too. For example, patients with leg pain may need to have a laminectomy, or removal of a lamina in the lumbar region of the spine. The process can successfully reduce leg pain and relieve pressure on compressed nerves in the low back, but it can involve the removal of so much bone that the spine becomes unstable. A spinal lumbar fusion can be necessary in this case, and the surgeon may perform it at the same time as the laminectomy.
How the Spinal Lumbar Fusion Surgery Proceeds
The spinal lumbar fusion surgery begins with administration of general anesthesia so that the patient is unconscious throughout the procedure. The patient also receives a dose of antibiotics to prevent infections from the surgery. After proper positioning of the patient in the operating room, the surgeon makes the surgical incision, with placement guided by x-ray technology.
A variety of interbody procedures are possible. They differ in how the surgeon approaches the spine and performs the fusion.
- PLIF and TLIF – In a posterior lumbar interbody fusion, or PLIF, and a transforaminal lumbar interbody fusion, or TLIF, the patient is gently positioned on his or her stomach, with care taken to avoid disturbing pressure points. The surgeon goes through the back to access the spine, and may use a synthetic cage to provide additional support in the disc space, or interspace, between the vertebral bodies.
- DLIF and XLIF – In a direct lateral interbody fusion, or DLIF, and an extreme lateral interbody fusion, or XLIF, the surgeon gains access to the spine by making the surgical incision through the side of the patient to avoid the muscles in the abdomen or back. These procedures also typically include the use of supporting materials in the disc space.
- ALIF – In an anterior lumbar interbody fusion, or ALIF, the surgeon gains access to the spine by making a cut in the front, while the patient is on his or her back, while cautiously avoiding disruption of the muscles in the abdomen.
- AXIALIF – In an axial lumbar interbody fusion, or AXIALIF, the surgeon gains access to the spine from the bottom of the spine. The surgical incision is behind the lower region of the spine, and the surgical tools are placed under the sacrum and coccyx.
- “360” fusion – In a “360” fusion, the surgeon fuses portions at the back and the front of the spine. The back portions can be fused at the facet joints, which act as protective areas between adjacent spinal levels, or they can be fused at transverse processes, which are bony outcroppings pointing towards the back of the spine. The front fusion occurs between vertebral bodies.
The difference between the PLIF and TLIF lies in the placement of fusion materials. The materials go on both sides of the midline in a PLIF, whereas they go diagonally across the spine in a TLIF.
In a “360” fusion, the surgeon can make a single surgical incision through the front, back or side of the body, or the surgeon can make incisions through the front and the back of the patient to gain optimal access to the spine.
In all types of interbody fusion to increase lumbar stability, screws are usually necessary for improving stability during healing. The screws can go through the pedicles of the vertebral bodies or through the facet joints. These screws are termed, respectively, pedicle screws and facet screws. The insertion of the screws requires either open surgery or a minimally invasive technique with multiple incisions in the patient’s skin.
Posterolateral fusion – The procedure can be used to supplement a lumbar fusion. It involves the laying of additional bone or other grafting material on the side and back of the spine so that as the lumbar fusion becomes complete, so does the union along the spine. This reinforces the strength.
Post-Op Patient Care
The patient is usually able to receive the discharge to go home in one to four days after the surgery. A back brace can be useful in preventing unnecessary movement that can disrupt bone fusion over the next few months. Also recommended are avoiding lifting heavy items, twisting sharply, or bending deeply.
Some discomfort from surgery can include back pain and spasms of the back muscle. These tend to get less severe in one to two weeks. The back incisions must not be wet until patients receive permission to get them wet at an office visit which usually happens in a week to 10 days after the procedure. Patients can go back to work when they receive clearance to do so. They may have to restrict strenuous activities at work.
Risks of the spinal lumbar fusion include infections and excessive bleeding, as well as nerve injury, spinal fluid leakage, and recurrence of symptoms. The fusion might not occur properly, leading to a non-fusion or non-union, and patients may have chronic spinal instability called pseudarthrosis.