Lateral Lumbar Interbody Fusion – a Minimally Invasive Method of Spinal Fusion
A number of surgical techniques exist to fuse the vertebrae of the lumbar portion of the spine in order to reduce or eliminate back and leg pain. A minimally invasive technique for accomplishing this spinal fusion is lateral lumbar interbody fusion, or LLIF. This is when the spine is accessed from incisions placed in the side of the body.
By accessing the spine from the side of the body, the surgeon is able to avoid separation of the lower back muscles, moving blood vessels aside, or cutting into bone. This lateral lumbar interbody fusion procedure is an effective treatment for a variety of spinal conditions, including disc degeneration, asymmetric disc degeneration, otherwise known as degenerative scoliosis, herniations, nerve impingement, and even some tumors.
In lateral lumbar interbody fusion, most of the affected disc is removed and a spacer is placed in order to restore or maintain proper disc height. Bone grafts are added to fuse the vertebrae above and below and provide spinal stability.
Lateral Lumbar Interbody Fusion Procedure Specifics
To begin, an incision approximately two inches in length is made at the side of the waist. In some cases it may be necessary to place a smaller incision behind it in order to help guide the surgical instrumentation. A fluoroscope is used to project live x-ray images of the procedure onto a screen, aiding the surgeon in guiding the procedure.
A narrow probe is inserted into the incision and directed through the psoas muscle towards the spine. The probe is attached to monitoring equipment that enables the surgeon to both detect and avoid nerves en route to the spine. The surgical opening is enlarged using a series of increasingly large dilators. A retractor device is positioned over these dilators in order to open up the surgical field. An endoscope or possible a microscope is used to give the surgeon close-up imagery of the procedure projected on a screen.
A sizable portion of the affected disc is then removed and replaced with what is called an interbody spacer. This spacer is composed of a support cage the size of a vertebral body. In addition to providing proper disc height, it removes pressure from any spinal nerve roots that were pinched by the degenerating disc. The interbody spacer is generally filled with processed bone or a bone graft substitute to encourage the regeneration of bone that will fuse the vertebrae.
Because lateral lumbar interbody fusion minimizes the trauma to surrounding tissue, the patient may experience a faster recovery than would be achieved using traditional surgical procedures. Patients can typically expect to return to normal activity three months following surgery.