Lumbar Fusion
If your low back pain already disrupts the quality of your life and lasts more than two weeks despite rest or self-care, see a doctor for proper evaluation. You may be experiencing symptoms of a serious condition affecting your lumbar spine or bones in the lower back. Lumbar fusion may be recommended if non-surgical treatment doesn’t relieve your pain.
What Is Lumbar Fusion?
To better understand how lumbar fusion works, it helps to learn a bit about the human spine anatomy. The human spine is made of many bones called vertebrae. The vertebrae’s center is a canal where the spinal cord runs through. Nerve roots branch off the spinal cord and pass through the small spaces between the vertebrae to travel into various areas of the body. The spinal discs lie between the backbones and act as spacers and shock absorbers.
The lumbar spine is made up of five vertebrae located in the lower back. The lumbar vertebrae are thicker and more prominent than the rest of the spine. They provide stability for the back and spinal column and support most of the body’s weight, especially the upper body. As such, problems in the lumbar spine can limit motion in the back or hips and cause weakness, pain and tingling or numbness in the back, thigh, hip or leg.
Lumbar fusion, or lumbar arthrodesis, is a surgical procedure to fuse one or more vertebrae in the lower back. Fusing the vertebrae reduces or eliminates movement between them, which may reduce pain. Lumbar fusion surgery may be recommended if motion is the source of pain.
Procedure
Imaging tests such as computed tomographic (CT) scanning, magnetic resonance imaging (MRI) and radiographs may reveal the extent of the lumbar spine damage. Your spine surgeon will perform lumbar fusion surgery under general anesthesia, putting you into a deep sleep. Your doctor may decide among these surgical approaches depending on the nature and location of your condition:
- Anterior approach – an incision will be made in the lower abdomen.
- Posterior approach – incision from the back.
- Lateral approach – approaching the spine from the side.
During spinal fusion, the surgeon may perform decompression procedures such as a laminectomy or discectomy. Laminectomy aims to remove pressure on the nerves in the lumbar area by removing the vertebrae's bone spurs and bone walls. On the other hand, a discectomy’s goal is to relieve spinal cord or nerve root pressure by removing all or part of a damaged lumbar disc.
After the decompression, your surgeon will place bone graft material along the sides of the affected vertebrae to stimulate bone growth. The graft may be harvested from the patient’s pelvis or a bone bank. The expected outcome is that the vertebrae heal together into one solid bone. The surgeon will implant screws and rods to secure the vertebrae and help with the fusion process, immediately providing stability to the lumbar spine while waiting for a solid bone fusion to develop. Your doctor may recommend wearing a brace to minimize movement in the surgical area.
When Is Spinal Fusion Necessary?
Your doctor may recommend conservative treatments, such as physical therapy and medications, to help relieve pain. Spinal fusion may only be recommended if non-surgical treatments do not improve your pain. Spinal fusion surgery may be recommended for patients with spinal instability, which can be characterized by the following:
- Structural deformity
- Loss of pain tolerance of the spine
- Nervous system damage due to strain or stress put on the body
Spinal fusion may also be needed to treat these conditions:
- Degenerative disc disease – characterized by the drying out of the disc’s nucleus pulposus, the gel-like structure that helps absorb shock. This dehydration may reduce the height of the disc, resulting in pain and abnormal motion due to the compression between the vertebrae. Disc disease can further minimize movement in the cervical spine and pinch the nerves.
- Spinal stenosis – the abnormal spinal canal narrowing, compressing the spinal cord or its nerve roots.
- Spondylolisthesis – poor spinal alignment due to a vertebra slipping forward on another vertebra. This condition can put pressure on the nerve roots or spinal cord.
- Scoliosis – the abnormal sideways curve of the backbone.
- Fracture – a broken bone
- Infection or tumor in the spinal column
