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Spinal Fusion

(Spinal Arthrodesis; Vertebral Interbody Fusion; Posterior Lumbar Interbody Fusion; Transforaminal Lumbar Interbody Fusion; Anterior Lumbar Interbody Fusion; Posterolateral Lumbar Fusion )


A spinal fusion is surgery to weld together two or more vertebrae so they heal into one strong bone. Vertebrae are the bones that make up the spine.

Reasons for Procedure

Spinal nerves leave the spine between the vertebrae. Damage to the vertebra and the disc that sits between them can put extra pressure on these nerves. This can cause pain and weakness in the areas of the body affected by the nerve. Spinal fusion may be done when other methods have not helped. A spinal fusion removes damaged tissue and locks the two vertebrae in place to prevent irritation of the spinal nerve between the vertebrae.

This surgery is done to ease pain and improve function. Spinal fusion may be done to treat problems, such as:

Possible Complications

Problems are rare, but all procedures have some risk. The doctor will go over some problems that could happen, such as:

  • Excess bleeding
  • Problems from anesthesia, such as wheezing or sore throat
  • Infection
  • Blood clots
  • A buildup of blood in the wound
  • Poor fusion of the bones
  • Nerve damage causing pain, numbness, tingling, or paralysis
  • Problems with bowel or bladder function
  • Injury to other structures, such as the nerves and blood vessels

Things that may raise the risk of problems are:

What to Expect

Prior to Procedure

The surgical team may meet with you to talk about:

  • Anesthesia options
  • Any allergies you may have
  • Current medicines, herbs, and supplements that you take and whether you need to stop taking them before surgery
  • Fasting before surgery, such as avoiding food or drink after midnight the night before
  • Whether you need a ride to and from surgery
  • Tests that will need to be done before surgery, such as images of the spine


The doctor may give:

Description of Procedure

Spinal fusion can be done by open surgery or using a minimally invasive technique. The exact steps will depend on the type of spinal fusion that is being done. Some examples are:

Interbody fusion uses the surfaces in between the vertebrae for fusion. The disc in between the vertebrae is either partly or fully removed. A cage (spacer) will be placed between the vertebra where the disc was removed. The cage may be made of plastic or metal. Bone grafts are used to help the bones heal together into one solid bone. It may be from a person's own bone, one from a cadaver, or artificial bone. Metal screws and plates may then be placed on the outside of the vertebra to keep the bones stable. There are three types of interbody fusion:

  • Posterior lumbar interbody fusion (PLIF)—the incision is made in the back. Muscles and nerves are moved out of the way. Part of the spinal bone may be removed to access the area between the vertebrae. The cage is placed from the back of the spine.
  • Transforaminal lumbar interbody fusion (TLIF)—the incision is made from the side. This allows access to the vertebra without a lot of movement to the muscles and nerves. It also does not require removing any bones. The cage is placed from the side of the spine.
  • Anterior lumbar interbody fusion (ALIF)—the incision is made in the lower belly. Organs and blood vessels are moved aside to access the vertebra. The muscles and nerves of the spine do not have to be moved. The cage is placed through the front part of the spine. No surgery is done on the outside of the vertebra.

Another option is posterolateral fusion . An incision is made in the back. The muscles are pushed aside to access the vertebra. Damaged bone and structures may be removed to ease pressure on spinal nerves. A graft will be placed along the outside of the vertebra to support bone healing and growth. Screws and rods may also be used to keep the bones stable while they heal.

The incision will be closed with stitches or staples.

Lumbar Fusion
Spinal fusion lumbar

A metal cage filled with bone graft is placed between lumbar vertebrae.

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How Long Will It Take?

4 to 6 hours or longer

How Much Will It Hurt?

Pain and swelling are common in the first month. Medicine and home care can help.

Average Hospital Stay

Most people leave in 3 to 4 days. If you have any problems, you may need to stay longer.

Post-procedure Care

At the Hospital

Right after the procedure, the staff may:

  • Give you pain medicine
  • Apply a back brace or cast
  • Teach you how to move, sit, stand, and walk

Physical therapy will be started soon after the procedure.

During your stay, staff will take steps to lower your chance of infection, such as:

  • Washing their hands
  • Wearing gloves or masks
  • Keeping your incisions covered

You can also lower your chance of infection by:

  • Washing your hands often and reminding visitors and staff to do the same
  • Reminding staff to wear gloves or masks
  • Not letting others touch your incisions

At Home

It will take a few weeks for the incisions to heal. It will take several months for the bones to fully fuse. Physical activity will be limited during recovery. You will need to ask for help with daily activities and delay return to work.

Healed Lumbar Fusion
Nucleus Image

Copyright © Nucleus Medical Media, Inc.

Call Your Doctor

Call the doctor if you are not getting better or you have:

  • Signs of infection, such as fever and chills
  • Redness, swelling, increasing pain, excessive bleeding, or discharge from the incisions
  • Nausea or vomiting
  • Pain that is not eased by medicine
  • Cough, shortness of breath, or chest pain
  • Numbness, tingling, pain, or weakness, especially in the arms, hands, legs, or feet
  • Swelling in the feet or legs
  • Loss of bladder or bowel control
  • Problems passing urine
  • Joint pain, fatigue, stiffness, rash, or other new symptoms

If you think you have an emergency, call for medical help right away.


Know Your Back—North American Spine Society

Ortho Info—American Academy of Orthopaedic Surgeons


Canadian Orthopaedic Association

When it Hurts to Move—Canadian Orthopaedic Foundation


Anterior lumbar interbody fusion. Ortho Info—American Academy of Orthopaedic Surgeons website. Available at: Accessed September 30, 2020.

Chronic low back pain. EBSCO DynaMed website. Available at: Accessed September 30, 2020.

Posterior lumbar interbody fusion and transforaminal lumbar interbody fusion. Ortho Info—American Academy of Orthopaedic Surgeons website. Available at: Accessed September 30, 2020.

Qaseem A, Wilt TJ, et al. Noninvasive Treatments for Acute, Subacute, and Chronic Low Back Pain: A Clinical Practice Guideline From the American College of Physicians. Ann Intern Med. 2017 Apr 4;166(7):514-530.

Spinal fusion. Ortho Info—American Academy of Orthopaedic Surgeons website. Available at: Accessed September 30, 2020.

Spine surgery: Lumbar interbody fusion. Hospital for Special Surgery website. Available at: Accessed September 30, 2020.

Last reviewed September 2020 by EBSCO Medical Review Board Warren A. Bodine, DO, CAQSM