Failed Back Surgery Syndrome (FBSS) Causes

Sometimes, the outcome of spine surgery isn’t as expected and causes a condition called failed back surgery syndrome (FBSS). Other names for the condition include failed back syndrome or surgery (FBS) and post-laminectomy syndrome. However, a laminectomy procedure is not always a cause or factor contributing to FBSS. There are many potential causes of failed back surgery and most times neither the patient nor the spine surgeon is to blame.

Back and/or neck pain are the foremost symptom of FBSS that may present days, weeks, months or years after spine surgery. Furthermore, symptoms may be the same, similar or different. Like any spinal disorder, a complete and thorough physical and neurological examination is essential to diagnosis and formulate an effective treatment plan.

Inflammation in the disc space, highlighted in red.There are many potential causes of FBSS and symptoms may develop soon after surgery or months later. Photo Source:

When Can FBSS Symptoms Start?

As with any medical condition, when pain or symptoms start is a piece of diagnostic information that is as important as a description of the symptoms. Below is an overview of the possible connection between when symptoms begin and the possible cause of FBSS.

Symptoms may …

Return immediately or develop soon after spine surgery.
There are several reasons that may be involved if pre-surgical or new symptoms recur or develop immediately or soon after surgery. Possibly the original diagnosis was incorrect, a surgical error occurred, the patient fell or incurred a physical accident after back surgery, or a pre-existing medical condition increased the risk for FBS.

Arise within a few weeks after back surgery.
A post-operative spinal infection may cause pain and other symptoms.

Begin a few months after spine surgery.
Pain and symptoms that develop a few months after spine surgery may be caused by a recurrent diagnosis (eg, herniated disc), epidural fibrosis (scar tissue forms around spinal nerve roots), or arachnoiditis.

Recur years after spine surgery.
Pain years after your spine surgery may be caused by degenerative changes in the spine, spinal instability (eg, spondylolisthesis) or spinal stenosis. These disorders may occur at the site of your surgery or at the next (adjacent segment disease) spinal level.1

Common Causes of Failed Back Surgery

Below are some of the most common causes of FBS.

Adjacent segment disease
Adjacent segment disease (also known as ASD or transitional syndrome) is a potential cause of failed back surgery syndrome after spinal fusion surgery. Because fusion is intended to stop movement at a spinal segment, the segments above and below it may overcompensate by moving more. This excessive movement can cause the adjacent levels to degenerate at an accelerated rate and become unstable, causing pain.

Arachnoiditis is inflammation of one of the three protective linings that surround the brain and spinal cord. It can cause severe burning and stinging pain and other nerve-related problems. People who have complex or recurrent spine surgeries are at an increased risk for developing this surgical complication.

Persistent neural decompression
Decompression surgeries remove bone and other impeding structures that are compressing spinal nerves. Despite decompression, sometimes there can be ongoing neural compression causing persistent radiculopathy.

Pseudoarthrosis—or non-union—is the medical term used to describe a complication of spinal fusion surgery that often involves instrumentation and fusion. Spinal fusion is performed to join two or more spinal bones (eg, vertebrae) together, with the goal of stabilizing one or more levels of the spine to stop movement. But if the bones don’t fuse—heal together completely or properly—patients may experience ongoing pain complaints and hardware may loosen. Pseudoarthrosis may cause or contribute to spinal instrumentation moving or breaking. The fusion process takes several months for spinal bones to heal together. During that time, several follow-up appointments with the surgeon are essential to monitor the progress of fusion to ensure it is healing properly.

Recurrence of earlier diagnosis
Sometimes, your original symptoms return after undergoing spine surgery. For example, a spinal disc treated with microdiscectomy may re-herniate. This does not mean your first surgery wasn’t a success or that the diagnosis was incorrect—sometimes, spinal problems return despite proper medical management.

Scar tissue problems: epidural fibrosis and spinal adhesions
Epidural fibrosis is a medical term that describes the formation of scar tissue around one or more spinal nerve roots. Epidural fibrosis may develop months after spine surgery, and it can cause a spike in pain. For people who had lumbar (low back) surgery, epidural fibrosis may lead to sciatica—radiating leg pain. Scar tissue after spine surgery can also form spinal adhesions, which are bands of scar tissue that pull together tissues that are not normally connected. Adhesions can prevent you from moving properly, and can press spinal nerves.

Spinal infection
Symptoms of post-surgical spinal infection include fever, wound drainage and redness, chills, and headache. These and other related symptoms typically show up a few weeks after surgery, but may arise anywhere between three days and three months after a spinal procedure. Infections (eg, vertebral osteomyelitis) occur in as many as 4% of surgeries, and people who have longer spine surgeries, spinal instrumentation, and recurrent spine surgeries have a higher risk for infection.2

Spinal instability
Spinal instability can develop after fusion surgeries (eg, ASD) or decompression surgeries (eg, if too much bone is removed to free up space around spinal nerves).

Spinal instrumentation problems
Spinal instrumentation (eg, screws, rods, interbody devices, plates) can help provide immediate spinal stability and provides a firm foundation for fusion. However, instrumentation can become infected, loosen, break, and/or move—and can cause a lot of pain. Your doctor can detect problems with instrumentation on an imaging scan (eg, x-ray, CT), but the decision of whether to remove the instrumentation is not as clear cut—benefits and risks come with undergoing a second surgery to remove the instrumentation.

Diagnostic error
Often the diagnosis or the cause of a patient’s pain is not certain. As part of the aging process, there are abnormalities on a person’s MRI that may be asymptomatic (ie, without symptoms). Surgeons estimate there is a chance of success with the surgery but other times the diagnosis is incorrect and the surgery fails to help the patient.

  • Though more than 50% of first-time spine surgeries produce good outcomes, no more than 30% of second surgeries, 15% of third surgeries, and 5% of fourth surgeries are successful.3
  • Even if the diagnosis and surgical recommendation are correct, complications may occur during surgery that can cause new pain and problems.

Uncompliant patient
When undergoing spine surgery, a patient may feel out of control—but that’s quite the contrary, as patients can make choices to improve their surgical outcomes. Several factors can increase the risk for failed back surgery. For example, smoking and obesity are shown to produce poorer spine surgery outcomes.

What Now? Once the Cause of Failed Back Surgery Is Confirmed

Once the doctor understands the root cause of a patient’s failed back surgery syndrome (FBSS), he or she will develop a treatment plan to ease pain, symptoms and restore quality of life. Because the spine surgery rate of success diminishes with each subsequent spine surgery, the doctor will most likely first suggest non-surgical treatments to manage pain and symptoms.

Updated on: 05/09/19
Continue Reading
Adjacent Segment Disease and Back Pain
Continue Reading:

Adjacent Segment Disease and Back Pain

Adjacent segment disease, a known complication of spinal fusion, can also be caused by degenerative changes in the back and neck.
Read More