What is an ALIF?

What Is Anterior Lumbar Interbody Fusion (ALIF)?

Anterior lumbar interbody fusion surgery, also known as ALIF, refers to a particular technique of performing a spinal fusion.

Anterior means that the spine is approached from the front, or through the abdomen. The exposure part of the operation is typically performed by a vascular surgeon working together with the spine surgeon, to provide safe access to the spine while protecting the major blood vessels.

Lumbar refers to the part of the spine that is in the lower back. Interbody refers to the disc space, or the cushion that normally exists between the two bones of the spine (vertebrae). Fusion means to unite the bones using bone graft so that instead of two separate bones that the bones grow together and move as one to provide stability.

All together, an ALIF is a surgical procedure where a spinal fusion is performed between two or more bones of the lumbar spine by removing the disc in between the two bones, and replacing it with a cage and bone graft to allow them to unite together. An ALIF can be performed for a variety of indications including degenerative disc disease, lumbar radiculopathy, or as part of a larger procedure done for adult scoliosis.

In most cases, an ALIF procedure is not performed in isolation but is combined with a posterior spinal fusion procedure also when the spine is approached through an incision in the back.

ALIF Surgery Procedure

While ALIF surgery used to require large incisions, the procedure can now be performed in a minimally invasive fashion for surgeons trained in modern techniques.  Anterior lumbar interbody fusion surgery is performed under general anesthesia. The patient is positioned on their back on the operating table. After cleaning the skin and placing sterile drapes, an incision is made over the front of the abdomen.

The vascular surgeon along with the spine surgeon then gently moves the abdominal contents including the major arteries and veins out of the way to expose the spine. The correct operative level is then confirmed with an x-ray. At this point the diseased disc is then completely removed using specialized instruments exposing the bone of the vertebral bodies on either side.

At this point a cage filled with bone graft (typically bone from a bone bank and/or a specialized protein to stimulate bone formation) is placed to reconstruct and fill the now empty disc space and to allow the bones to eventually grow together. Typically then a plate with screws is also affixed to the front of the spine to provide additional stability to increase the chance that the bones will successfully fuse.

Final x-rays are then taken, the retractors are removed, and the incision is closed. If other procedures on the spine are needed the patient is then repositioned on the operating room table and those procedures are started immediately after finishing the ALIF procedure.

What To Expect After Anterior Lumbar Interbody Fusion Surgery?

If ALIF surgery was performed for sciatica or lumbar radiculopathy pain traveling down the legs, patients will often notice that this pain is completely gone or significantly improved immediately after they wake up from surgery.

After ALIF surgery it is normal to have some abdominal pain which will resolve over several weeks as the muscles of the abdomen recover and heal.  Because a spinal fusion with an incision in the back is often performed concurrently with an anterior lumbar interbody fusion, back pain is also common during the recovery period which eventually will resolve.

Weakness and numbness in the legs can take weeks to months to recover, and in some cases may not recover completely depending on how long it had been present before surgery.

Anterior Lumbar Interbody Fusion Recovery Time

Patients that have an ALIF procedure alone can go home from the hospital once their pain is controlled on oral pain medication, and they are able to tolerate food without becoming bloated.  This is usually the first day after surgery. If however the ALIF was part of a larger spinal reconstruction, the hospital stay is usually 2-4 days.

Walking is encouraged immediately after surgery for exercise.  For the first 3 months after surgery, it is recommended to limit bending, twisting, or lifting > 10-15 lbs to decrease stress on the spinal instrumentation (cage, plate, screws, rods) to allow the fusion and healing of the bones to take place.

After 3 months, the fusion is usually healed enough to allow gradual return back to normal activities with a special focus on core strengthening. Formal physical therapy is rarely required. The fusion is typically not fully healed until at least 6 to 12 months after surgery.

Post-operative visits are recommended at 2 weeks, 6 weeks, 3 months, 6 months, 1 year, and 2 years after ALIF surgery.

Anterior Lumbar Interbody Fusion Surgery Risks

All spinal operations carry some risks, but in general these risks are low.

The most common risks after ALIF surgery are:

  • Abdominal pain at the site of the incision which usually resolves over several weeks

  • Risk of abdominal hernia at the site of incision

  • Risk of pseudarthrosis, especially if an ALIF surgery was performed without any posterior spinal fusion.  This is when the fusion does not heal and this can lead to eventually loosening of the screws and persistent or recurrent pain.  This risk is higher in patients that are overweight or smoke cigarettes

Some rare risks that are specific to ALIF surgery are:  

  • Risk of injury to the major blood vessels in the abdomen including the aorta, vena cava, or iliac arteries or veins.  The surgery is performed in conjunction with a vascular surgeon who carefully protects these vessels while the spine portion of the operation is performed.

  • Risk of injury to the abdominal contents such as the intestines or ureter (the tube which carries urine from the kidneys to the bladder)

  • Risk of retrograde ejaculation where semen flows backwards into the bladder which can cause infertility.  This risk does not affect the experience of an orgasm if present.

  • Persistent back pain, leg pain, numbness, and weakness.  Even if the surgery is successful and the spinal fusion heals successfully, there can be lack of full recovery of the nerves that may never recover

  • Risk of infection

If you have more questions or would like to schedule an appointment with Dr. Nemani to see if you are a candidate for an anterior lumbar interbody fusion surgery or ALIF surgery, please call 919-781-5600 or book an appointment online.