What is a spinal fusion?
Lumbar spinal fusion refers to an operation performed in the lumbar spine (lower back) that surgically unites two or more spinal bones (vertebrae) so that they grow together and move as a single bone, rather than two separate bones. A lumbar spinal fusion can be performed by a variety of techniques, including a posterior spinal fusion, posterior or transforaminal interbody fusion (TLIF), oblique or lateral lumbar interbody fusion (OLIF or XLIF), or an anterior lumbar interbody fusion (ALIF).
Sometimes these procedures are performed in combination as the exact operation is tailored to the patient’s specific needs and anatomy. Minimally invasive spinal fusions can also be performed using many of these techniques.
A lumbar spinal fusion can be performed for a variety of indications.
Most commonly it is recommended for a condition known as spondylolisthesis where there is instability of the vertebrae in the lower back that causes leg pain and back pain from nerve compression and spinal stenosis. Lumbar spinal fusion surgery can also be beneficial in cases of degenerative disc disease with predominately leg pain symptoms, spinal tumors, fractures causing instability, or spinal deformities such as scoliosis or kyphosis.
Lumbar spinal fusion is NOT recommended for patients with degenerative disc disease with mostly back pain and minimal or no leg pain, as it is not a reliable operation for the relief of back pain in this setting.
Lumbar Spinal Fusion Surgery Procedure
Please see the pages describing ALIF, OLIF, XLIF, TLIF for detailed descriptions on how these procedures are performed. All of these procedures involve access to the spine either through the front of the abdomen, the side or flank, or through the back and sometimes a combination of techniques.
In the most common type of operation (posterior spinal fusion with or without TLIF), an incision is made in the middle of the back over the involved levels of the spine. After the spine is exposed, screws are placed into the part of the bones called the pedicles to allow for rigid fixation of the spine. Then a lumbar decompression is performed to open up space for the nerves to relieve nerve compression.
If a TLIF is also performed, then the nerves are gently moved to the side and protected, and the disc is removed in its entirety and bone graft and a cage made of titanium and bone graft is placed into the empty disc space. Then rods are placed into the screws to secure them together and more bone graft is placed onto the back of the spine to allow the fusion to occur. The retractors are then removed and the wound is then closed.
In certain situations we are able to perform a minimally invasive spinal fusion. In these cases we combine an ALIF, OLIF, or XLIF with a posterior spinal fusion where the screws in the back are placed minimally invasively.
This can be done through small incisions in the back without having to do a traditional open approach to the spine which can result in a shorter hospital day and a faster recovery. However, not all patients are candidates for minimally invasive spinal surgery.
What to Expect After Lumbar Spinal Fusion Surgery?
If lumbar spinal fusion surgery was performed for severe leg pain, sciatica or lumbar radiculopathy pain patients will often notice that they have great improvement in their leg pain almost immediately after surgery. After lumbar spinal fusion surgery it is normal to have some back pain from the surgery itself which will resolve over the course of 4-6 weeks. Very rarely patients will have some persistent back pain after spinal fusion surgery even though everything has healed appropriately.
Weakness and numbness in the legs can recover more slowly and often takes weeks to months to improve. Rarely, these symptoms may never completely recover if they had been present for a long time prior to surgery.
Recovery Time for Lumbar Spinal Fusion Surgery
Lumbar spinal fusion recovery time varies depending on how extensive the procedure performed was.
Typically, most patients are able to go home after 2-3 days in the hospital. For minimally invasive spinal fusions, patients can often go home after 1-2 days in the hospital. Walking for exercise is encouraged immediately after surgery, beginning initially with two to three 5 minute walks each day, and gradually walking longer as tolerated.
For the first 3 months after surgery it is important to limit bending, twisting, or heavy lifting to decrease stress on the healing spinal fusion to allow the bones to heal properly and to decrease stress on the instrumentation (screws, rods, cages, etc.). After 3 months patients can then return to most activities as tolerated with a special focus on isometric core exercises (e.g. planks) and slowly working on regaining flexibility.
Patients often ask if they will lose flexibility after a lumbar spinal fusion and typically most patients do not perceive any loss of range of motion with a 1 or 2 level lumbar spinal fusion because there are many other levels of the spine which can still move. Athletes with lumbar spinal fusion will often have to delay return to sports until at least 6 months after surgery but this is determined on a case by case basis.
Post-operative visits are recommended at 2 weeks, 6 weeks, 3 months, 6 months, 1 year, and 2 years to monitor the recovery after lumbar spinal fusion surgery.
Lumbar Spinal Fusion Surgery Risks
All spinal operations carry some risks, but in general the risk after lumbar spinal fusion surgery are low.
The most common risks after lumbar spinal fusion surgery are:
Back pain at the site of the incision which usually resolves over several weeks
Risk of persistent back pain or leg pain, numbness or weakness. This is especially true if the symptoms have been present for a long time prior to surgery, or in patients with other medical problems that limit their healing potential (obesity, diabetes, elderly age, etc.)
Risk of pseudarthrosis, which is when the bones do not successfully fuse together. This can sometimes lead to loosening or even breakage of the spinal instrumentation which can result in recurrent pain. This risk is higher in patients with diabetes, who are overweight, or who actively smoke cigarettes. To decrease this risk sometimes a bone growth factor called bone morphogenetic protein (rhBMP-2) is used to increase the chances of a successful fusion.
Some rare risks that are specific to lumbar spinal fusion surgery are:
Risk of injury to the major blood vessels including the aorta, vena cava, or iliac arteries or veins. This is a risk in procedures performed from the front or side such as ALIF, XLIF, or OLIF and less so in TLIF or posterior spinal fusion procedures.
Risk of nerve injury
Risk of a misplaced screw or cage, or displacement of a previously well placed screw or cage that can result in nerve injury or pain
Risk of infection
Persistent back pain, leg pain, numbness, and weakness. Even if the surgery is successful and the spinal fusion heals successfully, sometimes patients will not fully recover due to a limited healing potential for the nerves.
Risk of a medical complication around the time of surgery such as a pneumonia, urinary tract infection, stroke, heart attack, or blood clot (DVT or pulmonary embolism)
If you have more questions or would like to schedule an appointment with Dr. Nemani to see if you are a candidate for lumbar spinal fusion surgery, please call 919-781-5600 or book an appointment online.