Post-laminectomy pain, also called failed back surgery syndrome (FBSS), is used to describe patients that present with persistent or recurring low back pain, with or without referred pain to the lower extremities, following one or more spine surgeries. Therefore, the outcome of the spinal surgery does not meet the expectation of the patient or surgeon.
Risk factors can be divided into three categories:
- Pre-operative: anxiety, depression, obesity, smoking, improper assessment of correct pain generator, litigation, or worker compensation cases. 1
- Surgical: revision surgery, poor surgical candidate or surgical issues e.g., selection of incorrect level of surgery.
- Post-operative: progressive disease such as recurrent disc herniation or spondylolisthesis, epidural fibrosis, nerve injury, infection, hematoma, progressive spinal stenosis, altered biomechanics, myofascial pain, adjacent level disease or pain sensitization.1,2
Epidemiology including risk factors and primary prevention
In 2002, there were more than 1 million spinal procedures performed2, with an increase of 170.9% between 1998 and 2008 of lumbar fusion surgeries.1 The incidence of FBSS has been estimated to be between 10% and 40%, depending on the type of surgery performed, responsible for more disability than any other condition.1,2 Risk factors are multifactorial and mostly intrinsic, including: pain sensitization and magnification, anxiety, depression, litigation or worker compensation cases, obesity, cigarette smoking, and trunk muscle imbalance.2,3,4,5 Identification of modifiable risk factors may help in prevention.
The pathogenesis of FBSS is mostly structural. Stenosis can remain after insufficient decompression, zygapophysial hypertrophy, or disc degeneration. Discectomy and fusion may alter spinal biomechanics, increasing the load on adjacent structures, which might result in increased disc degeneration on levels adjacent to the level of surgery.6 Pseudoarthrosis may result from poor surgical technique or failed fusion. Neuropathic pain may result from incomplete decompression, migration of pedicle screws, compression from scar tissue, local arachnoiditis, or centralization of pain unrelated to neural impingement. Myofascial pain can also be a pain generator, which may result from intraoperative insult to the muscles, compounded by postural changes in the postoperative period.3,4
Disease progression including natural history, disease phases or stages, disease trajectory (clinical features and presentation over time)
Persistent symptoms immediately after surgery might suggest technical issues, psychosocial overlay, severe nerve damage not alleviated by decompression, improper presurgical diagnosis, incomplete decompression or recurrent herniation. Early recurrence of symptoms occurring in the first one to five days should prompt imaging to evaluate for hematoma1 If the patient expresses relief initially, but pain returns in one or two weeks, an infection should be ruled out. When symptoms present months after surgery, recurrent disc herniation, spinal nerve trauma, or post-operative fibrosis should be considered. Pain that presents more than a year after surgical intervention might be caused by the development of adjacent segmental instability or stenosis.4
Specific secondary or associated conditions and complications
Patients might develop progressive pain and dysfunction. Success rates decrease for each surgical re-intervention, falling from 50% after the first repeat surgery, to 30% after the second, 15% after the third, and 5% after the fourth.4
2. ESSENTIALS OF ASSESSMENT
History should include pain location, pattern, quality, and temporal factors. Location of pain in the lower back (axial), vs. the leg (radicular), or both can help to differentiate etiology. Evaluation of red flags (nocturnal pain, weight loss, trauma, infection, saddle anesthesia, acute bladder and/or bowel incontinence or retention) and yellow flags (attitude that back pain is severely disabling, kinesiophobia, depression or anxiety, social withdrawal, and financial problems) should also be undertaken. Prior pain treatments (pharmacological and non-pharmacological), along with their efficacy, should be established. Validated low back pain scales, like the Pain Catastrophizing Scale, can be useful to quantify pain experiences.7
Vital signs and examination of abdominal, pelvic and vascular systems may be important. A focused spinal physical examination should include observation of scars, posture, spinal alignment, balance, and gait. Spinal range of motion must be evaluated. A complete motor and sensory neurologic examination should be included. Evaluation of the sacroiliac joints (SIJ), hips, and knees should complement the examination. Special tests to assess for nerve root tension signs must be performed (seated/straight-leg-raising test, femoral nerve stretch test). Non-organic findings that deviate from anatomic patterns of injury pathology, such as Waddell signs, should also be addressed. Some of the signs include disproportionate pain behavior, regional weakness, or altered sensation (whole-leg weakness or sensory loss), change in straight-leg-raise-test result after distraction, superficial or non-anatomic tenderness, and pain while simulating examination tests such as axial pressure in the skull. Presence of two or more signs may be indicative of psychological distress and is associated with poor outcome after surgery.5
If presence of significant yellow flags including co-existent mood disorder or signs of chronic pain syndrome, consider psychological consultation including a detailed neuropsychological assessment battery to ensure accurate diagnosis and help with subsequent treatment planning.
Pain might result in functional limitations such as diminished walking tolerance. Change in biomechanics and resultant mobility restriction may lead to an inability to perform daily activities, depression, or anxiety which impairs quality of life. The generic WHOQOL-BREF questionnaire can be used to evaluate quality of life, which studies have found to be directly related to postoperative recovery in FBSS patients.8 Amirdelfan K, Webster L, Poree L, Sukul V, McRoberts P. Treatment Options for Failed Back Surgery Syndrome Patients With Refractory Chronic Pain: An Evidence Based Approach. Spine. 2017 Jul 15;42 Suppl 14:S41-S52.
Laboratory studies will be guided by the history and physical examination. If infection is suspected, white blood cell count, erythrocyte sedimentation rate, or C-reactive protein are indicated. If abscess is suspected, open or percutaneous drain placement may be indicated. Blood cultures should be drawn to find causative organism, with most common microbe being Staphylococcus aureus 9
Imaging studies should be guided by the reported symptoms. Standing radiographs (X-Rays), including flexion, extension, and lateral bending views, can evaluate for segmental instability. Computed tomography (CT) can be used to assess for evidence of pseudoarthrosis. Magnetic resonance imaging (MRI) should be performed to evaluate discogenic pathology or foraminal encroachment. Nerve root enhancement, nerve root thickening, and extensive epidural fibrosis are all findings related to recurrent or residual symptoms.2 Contrast enhancement is necessary if the patient history is worrisome for infection in the intervertebral discs or vertebral bodies, and also helps to differentiate post-operative epidural fibrosis from recurrent disc herniation. Nuclear imaging also has a role in the evaluation for a possible infectious etiology as a cause of recurrent symptoms.10
Supplemental assessment tools
Electromyography and nerve conduction tests can help differentiate a more distal peripheral neuropathy from a radicular process. Selective nerve root blocks (SNRBs) may be useful in some patients for both diagnostic and therapeutic purposes, targeting particular nerve roots to identify a potential pain generator. If the pain is suspected to be coming from the zygopophyseal joint, a medial branch block may be performed. The SIJ may be susceptible to altered biomechanics following L5-S1 fusion surgery. If suspected, an SIJ block may be performed as another diagnostic and therapeutic tool.2,11 In recent years, accelerometers have been proposed as a tool to objectively evaluate functional recovery and document outcomes through activity.12
Early predictions of outcomes
One of the most important factors to consider in the prediction of outcomes is adequate patient selection for surgery, which includes psychological status. One common cause for poor surgical outcome is incorrect preoperative diagnosis. Patients with psychological disturbances, workers compensation or disability claims, abnormal pain behavior, depression and/or anxiety have poorer results after lumbar spine surgery.2,3,4,5 Awareness is growing on the concept of central sensitization, which accounts for chronic ‘unexplained’ low back pain. Hyperexcitable spinal neurons show reduced pain thresholds13 and may result in poor surgical outcomes. Identification and diagnosis may be difficult but extremely important for the creation of an adequate and specific treatment plan in the preoperative and postoperative phases14. Elective spinal surgery may need to be deferred till the underlying psychological issues are appropriately assessed and addressed.
Back pain is a common cause of work-related disability and accounts for some of the highest medical expenses for employers. The cost of treatment for the subset of patients that undergo surgical intervention is considerable. Spinal fusion surgery costs alone were estimated at 16 billion dollars in 20042. This figure does not take into consideration other factors such as home or work-environment adaptations.
Social role and social support system
Considering the role that psychosocial factors play in the development of this and other chronic pain syndromes, it is important to determine if the patient has adequate social support, as social stressors may perpetuate depression or anxiety.
Communication with the surgeon, understanding the type of surgery performed, post-operative precautions, and early implementation of post-operative rehabilitation are important considerations in treatment planning. Since failure to meet patient expectations partly defines this syndrome, adequate preoperative discussion and goal setting (stabilizing the spine vs. pain relief) is of paramount importance.
3. REHABILITATION MANAGEMENT AND TREATMENTS
Available or current treatment guidelines
Although no treatment guidelines are available, rehabilitative and medical treatments should be attempted before surgical reintervention, unless the patient presents with red flags, such as progressive neurologic deficits, or neoplasm. Management is based on identification of contributing factors, especially the quality of symptoms (axial vs. radicular). Since chronic pain is multifactorial, an interdisciplinary approach is valuable, along with establishing functional goals as benchmarks for treatment.
At different disease stages
Pharmacological therapy can be prescribed to facilitate the rehabilitation process. The choice of therapy will depend on the type of pain and the risk to benefit ratio of each medication. These might include acetaminophen, NSAIDs, COX-2 inhibitors, Tramadol, muscle relaxants, antidepressants, antiepileptics or opioids. Pharmacological approaches can be combined with modalities such as transcutaneous electrical nerve stimulation (TENS) and thermotherapy. Additionally, incorporating therapeutic exercise, with the goal of improving spinal stability and avoiding muscle weakness, is pivotal. The patient can be started on low-level aerobic training, lower extremity mobility, along with stretching and early muscle recruitment of abdominal and trunk muscles.
Other treatment modalities such as cognitive behavioral therapy and relaxation techniques can be integrated into the management of pain.
Procedural interventions should be included in the management program for patients who fail conservative therapy. These might include facet interventions, like medial branch blocks and radiofrequency neurolysis, epidural steroid injections, percutaneous epidural adhesiolysis, sacroiliac injections and intrathecal analgesic delivery implant systems.15, 16, 17, 18, 19
Recently, there is stronger evidence for the use of Spinal Cord Stimulators (SCS) in patients with FBSS, with emerging types of stimulation (low-frequency, high-frequency, burst and dorsal root ganglion stimulation) as different alternatives used for interventional pain management. Studies have demonstrated analgesic and functional efficacy in patients with radicular pain when compared to repeated lumbosacral surgery or conventional medical management. Metric measures included pain scores, quality of life, functional capacity and patient satisfaction. However, there is little evidence to suggest the same benefit in predominantly axial pain.19,20,21,22,23
Surgical revision for FBSS is associated with increased morbidity and low success rate. Revision surgery should be considered in cases where there is evidence of progressive neurological impairments, increased pain caused by hardware impingement upon the nerve root, objective evidence of reversible nerve compression, or segmental instability amenable to surgical stabilization or fusion.1
Coordination of care
An interdisciplinary team composed of physiatrists, therapists, spine surgeons and behavioral health experts intervening at different stages in treatment will provide the patient with the best chance at functional improvement.24
Patient & family education
The patient, family members, and caregivers should be oriented to the different factors that might affect clinical outcome. This might include early identification of psychological pathology, complications of surgery, adequate rehabilitation and surgical follow-up, along with harmful and beneficial behavioral modifications.
At this time there are no studies that evaluate the use of regenerative medicine on post laminectomy pain patients. However, even though future research is warranted, regenerative medicine may have an indication to address adjacent segment disease or other possible pain generators like discogenic pain disease. Intradiscal Platelet Rich Plasma is a potential effective management option for discogenic low back pain.25 Evaluation and measurement should be individualized and relies on self-reporting. Although not validated for FBSS, various tools are widely used for chronic low back pain. The Oswestry Low Back Pain Disability Questionnaire, Short-Form Health Survey (SF) 12 or 36, Visual Analog Scale, and the International Physical Activity Questionnaire could be used as tools to evaluate the efficacy of different treatment strategies, including a baseline measure prior to surgical intervention.
Translation into practice: practice “pearls”/performance improvement in practice (PIPs)/changes in clinical practice behaviors and skills
- Adequate patient selection prior to surgery is important in the prevention of FBSS.
- Appropriate diagnosis and management of underlying psychological issues is of critical importance in optimizing patient outcomes. Elective spinal surgery may need to be deferred till the underlying psychological issues are appropriately assessed and addressed
- FBSS is not a single entity, but a plethora of multiple potential etiologies. Causes may include surgical factors, mechanical factors, or central sensitization. Therefore, identifying the specific pain generator, keeping in mind the time frame when symptoms develop, is helpful in achieving early and successful pain management.
- It is important to implement a treatment plan through an interdisciplinary team approach, which should focus on achievable functional goals.
4. CUTTING EDGE/EMERGING AND UNIQUE CONCEPTS AND PRACTICE
Cutting edge concepts and practice
New treatment strategies are currently being studied, such as using peripheral nerve field stimulation (PNfS) in conjunction with spinal cord stimulation (SCS)23 , along with the incorporation of regenerative techniques for spine care. The link between symptomatic spinal stenosis and multifidi atrophy without correlation to the extent of muscle denervation would suggest that strengthening of the paraspinal muscles would make atrophy reversible and possibly alleviate axial pain.26 Assessment of brain remodeling and plasticity in patients with chronic pain by using functional MRI (fMRI), along with evaluation of individual genetic differences in endogenous pain modulation, could provide new tools in guiding therapy or tailoring different individualized treatment strategies.27
5. GAPS IN THE EVIDENCE-BASED KNOWLEDGE
Gaps in the evidence-based knowledge
- The use of opiates for chronic pain remains controversial. It is important to balance the risk for side effects, cost and abuse, with the benefit of achieving clear functional goals by providing proper analgesia.28,29,30
- The benefits of initial or repeated surgery, versus interventional pain management techniques, continues to be debated. Further research is required to determine which approach is more cost-effective and provides greater functional improvement.
- Baber Z, Erdek MA. Failed back surgery syndrome: current perspectives. J Pain Res. 2016;9:979-987.
- Chan CW, Peng P. Failed back surgery syndrome. Pain Med. 2011;12(4):577-606.
- Waguespack A, Schofferman J, Slosar P, et al. Etiology of long-term failures of lumbar spine surgery. Pain Med. 2002;(1):18-22.
- Bagnall D. Failed back surgery syndrome. In: Micheo W, ed. Musculoskeletal, Sports, and Occupational Medicine. 1st ed. New York, NY: Demos Pub; 2011:25-27.
- Youjeong K, Boden S. Update on the history and physical evaluation of a failed back surgery syndrome. Semine Spine Surg. 2008;20:236-239.
- Lee, Jae Chul, and Sung-Woo Choi. “Adjacent Segment Pathology after Lumbar Spinal Fusion.” Asian Spine Journal5 (2015): 807–817. PMC. Web. 20 Dec. 2017.
- Adams V, Walker B. Measurement Characteristics and Clinical Utility of the Pain Catastrophizing Scale in Individuals Experiencing Low Back Pain. Arch Phys Med Rehabil. 2016; 98:2350-1
- de Azambuja G, Regina M. Psychosocial and quality of life impact on patients with failed back surgery syndrome. Rev Dor. São Paulo,. 2015; 16(1):32-6
- Parchi, Paolo Domenico et al. “Postoperative Spine Infections.” Orthopedic Reviews3 (2015): 5900. PMC. Web. 20 Dec. 2017.
- Love C, Palestro CJ. Nuclear medicine imaging of bone infections. Clin Radiol. 2016 Jul;71(7):632-46
- Datta S, Everett CR, Trescot AM, et al. An updated systematic review of the diagnostic utility of selective nerve blocks. Pain Physician. 2007;10(1):113-128.
- Rao PJ,Phan K, Maharaj MM, Pelletier MH, Walsh WR, Mobbs RJ, Emerging role of accelerometry to objectively evaluate physical activity post spine surgery. J Clin Neurosci. 2016 Apr;26:14-8.
- Baron R, Hans G, Dickenson AH. Peripheral input and its importance for central sensitization. Ann Neurol. 2013;74(5):630-6.
- Nijs J, Meeus M, Van oosterwijck J, et al. Treatment of central sensitization in patients with ‘unexplained’ chronic pain: what options do we have?. Expert Opin Pharmacother. 2011;12(7):1087-98.
- Shapiro CM. The failed back surgery syndrome: pitfalls surrounding evaluation and treatment. Phys Med Rehabil Clin N Am. 2014;25(2):319-40.
- Ragab A, Deshazo RD. Management of back pain in patients with previous back surgery. Am J Med. 2008;121(4):272-278.
- Hussain A, Erdek M. Interventional pain management for failed back surgery syndrome. Pain Pract. 2014 Jan;14(1):64-78.
- Hayek SM, Helm S, Benyamin RM, et al. Effectiveness of spinal endoscopic adhesiolysis in post lumbar surgery syndrome: a systematic review. Pain Physician. 2009;12(2):419-435.
- Amirdelfan K,Webster L, Poree L, Sukul V, McRoberts P. Treatment Options for Failed Back Surgery Syndrome Patients With Refractory Chronic Pain: An Evidence Based Approach. 2017 Jul 15;42 Suppl 14:S41-S52.
- Bala MM, Riemsa RP, Nixon J, et al. Systematic review of the cost-effectiveness of spinal cord stimulation for people with failed back surgery syndrome. Clin J Pain. 2008;24(9):741-756.
- Frey ME, Manchikanti L, Benyamin RM, et al. Spinal cord stimulation for patients with failed back surgery syndrome: a systematic review. Pain Physician. 2009;12(2):379-397.
- Kumar K, Taylor RS, Jaques L, et al. Spinal cord stimulation versus conventional medical management for neuropathic pain: a multicentre randomised controlled trial in patients with failed back surgery syndrome. Pain. 2007;132(1-2):179-188.
- Reverberi C, Dario A, Barolat G. Spinal cord stimulation in conjunction with peripheral nerve field stimulation for the treatment of complex pain in failed back surgery syndrome. Neuromodulation. 2013;16(1):78-83.
- Chou R, Loeser JD, Owens DK. Interventional therapies, surgery, and interdisciplinary rehabilitation for low back pain: an evidenced-based clinical practice guideline from the American Pain Society. Spine. 2009;1;34(10):1066-1077.
- Monfett M, Harrison J, Boachie-adjei K, Lutz G. Intradiscal platelet-rich plasma (PRP) injections for discogenic low back pain: an update. Int Orthop. 2016;40(6):1321-8.
- Yarjanian JA, Fetzer A, Yamakawa KS, et al. Correlation of paraspinal atrophy and denervation in back pain and spinal stenosis relative to asymptomatic controls. PMR. 2013;5(1):39-44.
- Henry DE, Chiodo AE, Yang W. Central nervous system reorganization in a variety of chronic pain states: a review. PMR. 2011;3(12):1116-1125.
- Harden RN. Chronic pain and opiates: a call for moderation. Arch Phys Med Rehabil. 2008;89(3 Suppl 1):S72-76.
- Gallagher RM, Rosenthal LJ. Chronic pain and opiates: balancing pain control and risks in long-term opiod treatment. Arch Phys Med Rehabil. 2008;89(3 Suppl 1):S77-82.
- Saulino M, Schreiber A, Watanabe T. The appropriateness of long-term opioids to treat chronic back pain. PMR. 2012;4(4):304-311.
Original Version of the Topic
William F. Micheo, MD, Fernando L. Sepúlveda, MD, Roxanna Amill, MD. Post-laminectomy pain. 08/30/2013.
William F. Micheo, MD
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Fernando L. Sepúlveda, MD
Nothing to Disclose
Raul Rosario, MD
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Shirley Grigg, MD
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