Anterior Lumbar Interbody Fusion (ALIF): Everything You Need to Know

Spine surgery


ALIF stands for “Anterior Lumbar Interbody Fusion.” It is a surgical procedure used to treat lower back pain caused by degenerative disc disease, herniated discs, or other spinal conditions. In an ALIF surgery, the surgeon makes an incision in the front of the patient’s abdomen, near the lower back, to access the lumbar spine. The surgeon then removes the damaged disc between two adjacent vertebrae and inserts a bone graft or artificial disc into the space. This helps to stabilize the spine and promote fusion between the vertebrae, reducing pain and improving spinal function. ALIF surgery is usually performed under general anesthesia and may require a hospital stay of several days and have a recovery time of several weeks to months. 

First of all, what is a fusion surgery?

Spinal fusion surgery is a procedure that involves joining two or more vertebrae together in the spine. This is typically done to alleviate pain caused by conditions such as spondylolisthesis, scoliosis, or spinal fractures. During the surgery, the surgeon will use bone grafts and/or metal hardware (such as screws and rods) to hold the vertebrae in place while they fuse together during the healing process. The goal of the surgery is to stabilize the spine and reduce pain and nerve compression.

What are the different types of spinal fusion, and how is ALIF different?

There are several different types of spinal fusion surgeries for the back, each with their own unique approach and techniques. Some of the most common types of spinal fusion surgeries, other than ALIF include:

  • Posterior lumbar fusion (PLF): In a PLF surgery, the surgeon accesses the spine from the back of the body and fuses two or more vertebrae together using bone grafts or other materials.
  • Transforaminal lumbar interbody fusion (TLIF): In a TLIF surgery, the surgeon accesses the spine from the back, but enters the disc space from one side to remove the damaged disc and insert a bone graft or other material.

One of the main differences between ALIF and other types of spinal fusion surgeries is the approach used to access the spine. ALIF is unique in that it accesses the spine from the front of the body, rather than from the back. This allows for a more direct and thorough access to the damaged disc, while minimizing disruption to the back muscles and nerves.

Which conditions can be treated with an ALIF?

Spinal fusion surgery is typically indicated for conditions that cause pain or instability in the spine. Some common indications for the surgery include:

  • Degenerative disc disease: This is a condition in which the discs between the vertebrae begin to wear down, leading to pain and instability in the spine.
  • Spinal fractures: Fractures in the vertebrae can cause instability and pain in the spine.
  • Spondylolisthesis: This is a condition in which one vertebra slips forward over another, which can lead to instability, nerve compression and pain.
  • Scoliosis: This is a condition in which the spine is curved to one side. This can lead to uneven pressure on the vertebrae and cause pain. A fusion surgery is often used to correct the deformity from scoliosis. 
  • Tumors: Spinal tumors can cause pain and instability, especially if they erode through vertebrae. 
  • Instability from Surgery: A fusion surgery is sometimes needed to stabilize the spine after a decompression surgery such as a laminectomy

When is an ALIF used over other types of fusion surgeries?

One of the main advantages of ALIF is that it allows the surgeon to access the spinal discs from the front of the body, without having to disrupt the back muscles and nerves. This can result in less pain and a faster recovery for the patient.

ALIF may be preferred over other types of spinal fusion surgery in the following situations:

  • When the spinal condition is located in the lower lumbar spine: ALIF is most commonly used to treat spinal conditions in the lower lumbar spine, such as L4-L5 and L5-S1. This is because the front of the lower spine is more accessible than the back, and the ALIF approach can provide a more direct and thorough access to the damaged disc.
  • When the patient has had previous back surgery: If a patient has already had back surgery, scar tissue may have formed that makes it more difficult to access the spine from the back. In such cases, an ALIF approach may be preferred to avoid disturbing the scar tissue and nerves in the back.
  • When the patient has a spinal deformity: In some cases, a patient may have a spinal deformity, such as scoliosis or kyphosis, that makes it difficult to access the spine from the back. An ALIF approach may be preferred in such cases to avoid the deformity and provide a more direct access to the damaged disc.

What happens during the surgery?

An ALIF surgery typically takes several hours to complete and is performed under general anesthesia. Here is a general overview of what can be expected during the surgery:

  1. Incision: The surgeon will make an incision in the lower abdomen to access the spine. The length and location of the incision may vary depending on the patient’s anatomy and the extent of the surgery.
  2. Dissection: The surgeon will carefully dissect through the layers of muscle and tissue to expose the spine. The organs and blood vessels in the abdomen will be gently moved aside to avoid injury.
  3. Disc removal: The surgeon will remove the damaged disc or discs from between the affected vertebrae, which may involve removing a portion of the vertebral bone to access the disc.
  4. Bone graft or artificial disc placement: The surgeon will prepare the space between the vertebrae for a bone graft. The bone graft may be taken from the patient’s own hip bone or may come from a donor. An artificial disc, made out of special metal or plastics, may also be used.
  5. Instrumentation placement: The surgeon will place metal screws and rods or cages to support the spine and promote fusion between the affected vertebrae.
  6. Closure: The surgeon will close the incision with sutures or staples and cover it with a sterile bandage.

After the surgery, the patient will be taken to a recovery room to allow the anesthesia to wear off. Most patients will spend several days in the hospital after the surgery to ensure a safe recovery.

What is the recovery time following an ALIF?

In most cases, you can expect to spend 1 to 3 days in the hospital following a fusion surgery.  The duration of your stay will depend on your level of pain control and your ability to move around.

It is common for patients to begin standing and walking the day after surgery. Your surgeon may give you a back brace to help you feel more comfortable and to protect the surgical fusion.

During the first several weeks after the surgery, you should be able to perform basic exercises like walking but should avoid activities such as bending, twisting, or lifting heavy objects during this time.

Most patients who undergo a fusion procedure should expect to gradually resume their normal activities over a period of several months.

What are the risks of an ALIF?

As with any complex operation, there are several risks associated with spinal fusion surgery. Some of these risks include:

  • Infection: Although surgery is performed in sterile conditions, there is always a small risk of infection at the surgical site. 
  • Nerve damage: Nerves in and around the spinal cord can be damaged during the surgery.
  • Damage to other surrounding tissues: Other tissues as well as blood vessels and organs can be damaged during the procedure.
  • Non-union: The vertebrae may not fuse together properly, which may require additional surgery.
  • Adjacent segment disease: Adjacent segment disease can occur when the segments of the spine above or below the fused area become damaged or degenerate.
  • Hardware complications: There is a risk that the hardware used to fuse the vertebrae together may become loose or cause irritation.

Is an ALIF right for me?

It’s important to consult with a qualified spine surgeon to determine if an ALIF is the right option for you. 

There are many factors to be considered, including the specific condition being treated, your overall health, and your goals and expectations.

It’s also important to note that spinal fusion surgery is not always the best option for everyone. Some patients may be better served by other treatments, such as physical therapy, medications, or minimally invasive procedures.

About the Author

Dave Harrison, MD

Dr. Harrison is a board certified Emergency Physician with a part time appointment at San Francisco General Medical Center and is an Assistant Clinical Professor-Volunteer at the UCSF School of Medicine. Dr. Harrison attended medical school at Tufts University and completed his Emergency Medicine residency at the University of Southern California. Dr. Harrison manages the editorial process for