Experts discuss poor alignment as cause of failed back surgery syndrome, which treatments work
Defined as persistent back or leg pain following back surgery, failed back surgery syndrome is a broadly defined disorder that negatively affects thousands of patients each year and a problem that spine surgeons seem to address more regularly than ever before.
Source: : Midwest Orthopaedics at Rush
There is no equivalent term for a condition like failed back surgery syndrome (FBSS) in other medical specialties, Kern Singh, MD, of Midwest Orthopaedics at Rush, in Chicago, told Spine Surgery Today, and therefore the syndrome lends itself to many mischaracterizations about what FBSS is and what it is not, he said.
“The problem with using this broad classification is often the surgery is blamed, but we do not know what the indications for surgery were or the fact that surgery was addressing a particular pathology. Sometimes people undergo back surgery but actually have hip problems, sacroiliac joint problems or something not related to their back,” Singh, a Spine Surgery Today Editorial Board member, said. “They have persistence of pain and blame the spine surgery itself.”
Singh said he does not use the term FBSS unless there is definable evidence that surgery was indicated and it was for the diagnosis for which the patient was operated on.
“You have to make sure the surgery is done accurately. Often I see people diagnosed with FBSS who still have residual stenosis, a nonunion present, or screws or instrumentation that was incorrectly placed. So they have a reason for the persistent pain. It is not just because surgery was done,” he said.
Immediately blaming the procedure when a patient still presents with pain in the back or leg is not FBSS, according to Singh. The main reason spine surgery fails is because a surgeon might not have had a good indication to operate. Frequently patients are operated on who do not need surgery or will not benefit from it. To blame the procedure and say it is FBSS is not true. A better name for that situation is something like “failed indication surgery” and not FBSS, he said.
Singh said he believes there is a true FBSS diagnosis, but unfortunately the syndrome has become an all-encompassing umbrella for some patients and physicians.
“There is a component to FBSS, but it is much smaller than what it is being attributed to. Part of the problem is we never really truly understand the true indication for the original surgery, and there are so many psychosocial factors that occur, whether it is underlying depression or medical legal representation. All of those cloud outcomes associated with spine surgery,” he said.
The broad definition of FBSS lends itself to problems, Thomas J. Errico, MD, of NYU Langone Medical Center in New York City, told Spine Surgery Today.
Thomas J. Errico
“The term failed back surgery syndrome gets lumped into a lot of things; if you solve a patient’s problem, and then a year or two later they go on to have adjacent segment disease, that gets labeled, unfortunately, as failed back surgery syndrome,” he said. “I do not know where that came from. It does not have precedence in medicine. If you come to me with two clogged arteries, I put stents in, and 2 years later you do not change your habits and I have to put in two more stents — that is not called failed stent surgery.”
However, if FBSS is accurately diagnosed, with a proper surgery performed that failed to address the disorder it was intended to treat, then it is important to find out why the initial surgery did not work, according to Errico.
Structural or nerve problem
Typically surgery can fail due to either a structural problem or nerve damage or it may even arise for psychosomatic reasons.
“For a primary case, I look for the pain generators,” Errico said, noting when the problem is related to the nerves as the pain generator, it is fairly easy to diagnose as nerve compression is typically present. The solution in such a case is treatment to relieve any nerve pressure.
A backache that occurs postoperatively is more of a problem, he said. In such cases, Errico said he determines if the patient’s pain is coming from the disc, which is discogenic pain, or from the posterior elements, facet joint and capsule, he said.
“We can use a series of diagnostic blocks which temporarily relieve the pain, so, you have to be quite careful. I try and make sure a patient has a good psychological profile and try to isolate where the pain is coming from before deciding on a treatment,” Errico said.
Underlying factors can affect FBSS
Putting a patient through several initial tests can go a long way to determine the cause of their FBSS, Tyler R. Koski, MD, of Northwestern University, told Spine Surgery Today.
Tyler R. Koski
Understanding a patient’s initial pathology, why they first received back or spine surgery and whether it properly addressed the issue is extraordinarily important, he said.
“I do full standing X-rays whether it is a scoliosis X-ray or something else. We are fortunate to have a new EOS (EOS imaging: Cambridge, Mass.) scanner that does a head-to-toe look at alignment and compensatory mechanisms. I put them through all of that to get a thorough look at what is going on,” Koski said. “Then I am looking at MRIs and other imaging modalities, looking for scar tissue formation around nerves or if they are having leg pain. I am looking for all the other ‘red flags.’”
Koski also takes into consideration such conditions as fibromyalgia, which can cause pain but are not of a structural origin.
When it comes to FBSS, often a spine procedure could have been perfectly performed and shown to address all issues of the problem and the pathology it was meant to treat. In addition, the postoperative images were good and the procedure addressed the pathology it was meant to address, however, the patient still complains of pain. Often, this may be related to the patient’s expectations of the surgery and their self-perception, Singh said.
There are many examples of this in the FBSS literature, he said. These studies show the effect that psychosomatic issues can have on the outcomes of a procedure.
“Patients have a hard time understanding they may have persistent discomfort, but that this is not a failure of the procedure,” Singh said. “A lot of the treatments I render for these types of patients are psychosomatic treatments, making sure there is no underlying component of depression. I make sure they know the pain will not prohibit them from doing activities they enjoy and give them perspective on their outcome. That has been shown to be effective in treating some cases of FBSS.”
Patients who possibly have a secondary gain from FBSS — a lawsuit or a worker’s compensation claim — were more likely to be afflicted with FBSS, Kim J. Burchiel, MD, FACS, FAANS, told Spine Surgery Today.
Kim J. Burchiel
If patients have a reason to not get better, a reason to remain injured, then the odds are that the FBSS diagnosis will remain and they will never have a full recovery, he said.
A patient must have the desire to get better in order to be treated well and to recover from their injuries, Burchiel, head of the Department of Neurological Surgery at Oregon Health and Science University in Portland, Ore., said.
“It is one of many factors a surgeon has to think about before offering surgery: What is the secondary gain for a patient and what do they have to gain? Is this patient going to be a good candidate to rehabilitate themselves?” Burchiel said. “I think you have to take a rehabilitative approach. That is the first thing. But, if a patient is completely passive about their rehabilitation, it is unlikely anything is going to profoundly help them.”
Without the desire or a need to return to work, it can be very difficult to do so, Burchiel said. He cited a study by Waddell and colleagues that showed strong evidence the longer a worker waits to go back to work due to low back pain or FBSS, the lower the odds of them ever returning.
Investigators noted in the study that once a worker misses between 4 weeks and 12 weeks of work, they have a 10% to 40% chance of not returning to work for a full year. If a patient has missed 1 year to 2 years of work due to their injury or surgery, the odds are they will never return to work again.
Some of this is because patients may have unrealistic goals after surgery and after being out of work a while that they must return to work and should be able to do so. But more often than not, the patient thinks this is what the physician wants to hear, according to Burchiel.
More typically, patients who have been out of work for 2 years or 3 years are individuals who will not return to work at all.
Worker’s compensation claims can also muddle a diagnosis of FBSS, Singh said. There seems to be an abnormal number of patients with an FBSS diagnosis who are involved in a worker’s compensation claim, an accident claim or a personal injury claim, he said.
“I think the problem with the diagnosis goes back to, in general, the diagnosis was made in patients who have medical legal representation involved. That is where the diagnosis is most prevalent. Those are patients who are not necessarily incentivized to say their symptoms have improved,” Singh said.
Another situation in which the FBSS diagnosis issue is common is in the patient population that is biased or had a negative outcome from the start, according to Singh.
Depression and FBSS
Depression issues that affect patients can also lead to a higher diagnosis rate for FBSS, Christopher L. Shaffrey, MD, FAANS, of the University of Virginia Health System, told Spine Surgery Today. Preoperative screening for depression can help a surgeon determine the best course of action for treatment.
Christopher L. Shaffrey
Many studies have shown a definite link between FBSS and depression in patients. Treating a patient preoperatively for depression can go a long way toward ensuring they experience a positive outcome from their spinal surgery, he said.
“There are many patients referred for FBSS and the evaluation includes assessing potential sources for the pain that can be treated. It has been demonstrated that patients who fail lumbar surgery disproportionately are affected by depression or anxiety disorders more than the general population. Screening — and treating when present — anxiety disorders and depression is important,” Shaffrey said. “The evaluation should continue with potentially treatable structural causes, such as poor spinal alignment, residual or new neural compression, loosening of implants or evidence of a nonunion when a fusion is performed. Other conditions, such as proximal and distal junctional failure, should be evaluated.”
Treatment options differ
There are a number of treatment options for patients with FBSS, Shaffrey said. These should be considered based on the cause of the syndrome. For example, if it is structural, then patients should get a 36-inch long standing radiograph.
“If there has been no spinal instrumentation, then an MRI (usually with and without contrast) is a first step. If instrumentation is in place, a CT myelogram is usually the diagnostic procedure of choice to evaluate residual neural impingement, whether a nonunion is present and whether the spinal instrumentation is loose or broken,” Shaffrey said. “Other studies, such as EMG and nerve conduction studies, can sometimes be helpful when there is associated radicular pain, weakness or numbness.”
Misalignment problems can also be a leading cause of FBSS, according to Koski. He agreed a standing radiograph is a necessity for patients diagnosed with FBSS to see if they are misaligned. Furthermore, obtaining a global alignment picture of a patient can be helpful, especially when many of the patients have only an MRI or short-segment lumbar film or cervical film, Koski said.
“If it is an alignment problem, that is something that is correctable and you get pretty good results. I always tell people that come in looking for help with FBSS that at that point there is nothing I or anyone else can do to make their spine normal again. We are just trying to get it well-balanced, stable and structurally competent for them to be the best they can be,” Koski said. “When it is an alignment problem, that is a rewarding thing to treat. Those patients are very thankful. I cannot tell you how many patients I have seen who have been from doctor to doctor with significant problems who tell them there is nothing that can be done, and then years later they are sitting in front of me and it is a fairly straight forward fix, and those patients do well.”
Spinal cord stimulation options
Making sure a patient who may have FBSS is in the right mindset is also important, Singh said. Frequently patients have a hard time understanding they will have persistent discomfort, but that the discomfort does not signify the failure of the procedure
Spinal cord stimulation can work in some of these cases, he said, particularly in patients who have lingering leg pain. If the pain is anatomic and correlates to a particular nerve root, and there are no compressive lesions on the postoperative imaging, a spinal cord stimulator can help mitigate the symptoms for those patients, he said.
“But to treat just back pain after spine surgery with spinal cord stimulators, that has very little evidence to support it works,” Singh said.
Errico said treating pain using something such as deep brain stimulation is an interesting theory for FBSS, but it is a technique that is just now in its early stages. Deep brain stimulation would most likely be useful for a patient who did not need spine surgery in the first place. The concept of attacking the sensation of pain by stimulating the brain is interesting, although it is not viable yet for FBSS, according to Errico.
“I think increasingly we are coming to know that certain patients have central sensitization to pain. In other words, the pain is actually coming from neurotransmitter imbalances deep inside the brain that can be stimulated or corrected either through the vagus nerve or direct stimulation in the brain. I think we are in the infancy on this type of problem,” he said. “As spine surgeons, we attack backache or leg pain. But what about a patient who has backache and leg pain in the setting of a multisymptom complex of anxiety, depression, and maybe headache? Those things should be a red flag that maybe you are dealing with a larger global disorder than a primary backache condition.”
When there is no treatment
Without a clear-cut anatomical reason for their disorder, Shaffrey said further revision surgeries in patients with FBSS typically result in poor outcomes. Furthermore, he said patients with substantial “baggage” due to prior treatments can be challenging to properly evaluate and manage. But, when a structural abnormality is found in a patient and it can be corrected, revisions are typically successful, Shaffrey said.
“When there is a clear-cut case of poor alignment, nonunion or neural compression, the results can be extremely gratifying with marked improvement in pain and function following revision surgery,” he said.
Sources who spoke with Spine Surgery Today for this article noted that unfortunately, for a large subset of patients with FBSS there is nothing that can be done in regard to surgery or corrective techniques.
Koski said these patients may have to go back to the beginning of their treatment or just have to rely on pain management approaches for their syndrome for the rest of their lives.
When FBSS is an accurate diagnosis, it can be really difficult for a patient to deal with. They have a lot of pain and are usually searching for answers, according to Koski.
“It is important for people to know that sometimes there is nothing that can be done and you are back to trying to treat pain the best way you can, and more surgery sometimes is not the answer,” he said, and a conversation about that is one of the hardest ones to have with a patient. “But I have found an even harder topic to discuss with patients, after a thorough assessment to identify the cause of possible FBSS, is that they have a chronic pain syndrome and nothing more can be done.” – by Robert Linnehan
References:Hussain A. Pain Pract. 2014;doi:10.1111/papr.12035.
Waddell G. Occup Med. 2001;doi:10.1093/occmed/51.2.124.
For more information:Kim J. Burchiel, MD, FACS, FAANS, can be reached at Oregon Health and Science University, 3181 Southwest Sam Jackson Park Rd, Portland, OR 97239; email: email@example.com.
Thomas J. Errico, MD, can be reached at New York University Langone Medical Center, 333 East 38th St., New York, NY 10016; email: firstname.lastname@example.org.
Tyler R. Koski, MD, can be reached at Northwestern University, 675 North Saint Clair St., Chicago, IL 60611; email: email@example.com.
Christopher L. Shaffrey, MD, FAANS, can be reached at University of Virginia Health System Neurological Surgery Department, 1215 Lee St., Charlottesville, VA 22908; email: firstname.lastname@example.org.
Kern Singh, MD, can be reached at Midwest Orthopaedics at Rush, 1725 West Harrison St., Chicago, IL 60612; email: email@example.com.
Disclosures: Errico is an employee of NYU Langone Medical Center, which received a grant from the Orthopedic Medical Educational Grants Association (OMEGA) for fellow support; a grant from the Fridolin Trust for research coordinator support (past) and from Paradigm Spine for research coordinator support (past). Errico receives royalties and payment for lectures from K2M and royalties from Fastenetix and is an unpaid committee member of the Harms Study Group. He also receives ongoing medical publisher’s payment for textbooks (less than $500) from Elsevier. Singh is a consultant for DePuy, Globus, Stryker, Bioventus and Pioneer; receives royalties from Thieme, Lippincott, Stryker, Zimmer and Pioneer and is on the board of directors of TruVue Surgical, Vital 5 and Avaz. Burchiel, Koski and Shaffrey have no relevant financial disclosures.
Which method best controls the neuropathic pain associated with failed back surgery syndrome: Spinal cord stimulation or conventional medical management?
Techniques continue to evolve
The most common causes of failed back surgery amenable to surgical correction are residual or recurrent herniation and foraminal stenosis that is unrecognized, untreated or undertreated. Both are common causes of neuropathic pain and are correctable with transforaminal endoscopic decompression without causing more surgical morbidity or more surgical scarring.
Because the question is specific to spinal cord stimulation, I will address treatment for neuropathic conditions from permanent neuropathic pain from battered nerve root syndrome, traumatic neuropathy and conditions, such as arachnoiditis, that may have no surgical solution and require methods to treat neuropathic pain documented to have neuropathy on diagnostic studies, such as EMG and conduction studies.
Anthony T. Yeung
Since 1967, the main method of neuromodulation for the management of chronic, intractable pain of neuropathic origin has been the stimulation of the dorsal column by electrodes in the epidural space. Clinical practice, however, has shown it is difficult to consistently target multiple dermatomes needed in complex pain syndromes, and long-term success has been generally limited.
The evolution of introduction of dual-electrode stimulation with staggered contacts and electrodes with smaller inter-contact spacing improved clinical outcome, but variability and lasting effects among patients remained.
Chronic pain management approaches have and will continue to evolve. One such approach is to target specific nerve dermatomes by modulation of the dorsal root ganglion instead of the spinal column and the use of wireless neuromodulation. With newer percutaneous techniques, delivery of the electrode to the specific nerve root instead of the spinal column simplifies the technique and has the advantage of implanting the electrode under local anesthesia. The patient can provide immediate feedback of any effect on pain relief before the implant is secured percutaneously.
Medical management is an adjunct that is more effective early in the presentation of lumbar pain syndromes. A highly structured rehabilitation intervention, including a cognitive-behavioral component, could result in a more favorable outcome for nonoperative treatment. Electrical stimulation of the spinal cord, however, provides effective pain relief to thousands of chronic neuropathic pain sufferers. The stimulation depolarizes axons and generates propagating action potentials that interfere with the perception of pain. In vivo electrophysiological recording can bring neuropathic pain sufferers to a broad range of evolving neuromodulation therapies.
Anthony T. Yeung, MD, practices at the Desert Institute for Spine Care, in Phoenix.
Disclosure: Yeung is an investor in and the Chair of the Medical Advisory Board of Stimwave Technologies Inc., co-inventor and method patent of “Methods and devices for modulating excitable tissue of the exiting spinal nerves,” Patent number 8,903,502. He is a developer of the Richard Wolf Endoscopic Spine System (YESS) and receives royalties from Richard Wolf for the YESS system.
An umbrella diagnosis
Failed back surgery syndrome is an all-encompassing term for patients with persistent or recurrent low back and leg pain following previous surgical intervention. Beneath this “umbrella” diagnosis are patients with arachnoiditis, iatrogenic or other nerve injury and neurological deficit, pseudoarthrosis that has failed revision, deformity of the spine, dense epidural and intramuscular scar formation, etc. Some patients labeled with failed back surgery syndrome (FBSS) actually have none of the above and demonstrate normal neurological function on examination, a solid arthrodesis on radiographic imaging (if fusion was performed), and/or satisfactory decompression of the spinal cord or cauda equina or individual spinal nerve roots.
The spine specialist must be diligent in assessing all potential factors leading to the labeled FBSS patient’s chronic pain to exclude the possibility further surgical intervention could be necessary. For example, many patients on chronic opiate and other pharmacologic regimens or patients referred for a trial of percutaneous spinal cord stimulation (SCS) actually harbor potentially fixable pathology such as pseudoarthrosis, adjacent level instability, adjacent level stenosis, progressive deformity, unsatisfactory spinal implant placement or failure, symptomatic pseudomeningocele or other pathology. If any of these are identified and felt to correlate with the FBSS patient’s pain syndrome, then serious consideration should be given to correcting the abnormal finding.
Gerald E. Rodts Jr.
For those FBSS patients for which no further direct spinal surgery is felt to be helpful, oral pain medication regimens, narcotic intrathecal pumps and SCS remain important strategies. The benefits of SCS over reliance upon narcotic medication is obvious. Historically, however, electrical SCS has been most effective in treating chronic radicular symptoms and results in alleviating low back pain have been disappointing or mixed. Recently, however, more extensive multi-column electrodes (with more surface contacts) have become available and are proving more effective in alleviating low back pain and radicular symptoms. In fact, many surgeons are recommending percutaneous trials of SCS for FBSS patients who have predominantly or exclusively low back pain. This technological advance brings even greater promise and hope for FBSS patients suffering from both severe low back pain and leg pain.
Roulaud M. Neurochirurgie. 2014;doi:10.1016/j.neuchi.2014.10.105.
Gerald E. Rodts Jr., MD, is Professor of Neurosurgery and Professor of Orthopaedic Surgery at Emory University, The Emory Spine Center, in Atlanta.
Disclosure: Rodts is a consultant to Medtronic (Sofamor Danek) Inc., Globus Medical Inc., Orthofix Inc. and the U.S. Department of Justice. He receives royalties from Globus Medical and is a co-founder and stockholder in spineuniverse.com.