Transforaminal Epidural Steroid Injections

Two Approaches to Transforaminal Epidural Steroid Injections for the Treatment of Radiating Low-Back Pain

What is the Evidence?

Low-back pain is common. In fact, up to 80% of us will experience this pain. The lower back is a complex network of spinal muscles, nerves, bones, discs or tendons in the spine. An irritation, problem, or damage to any of these parts may cause pain in the lower back that often travel to other areas of the body. Fortunately, lower back pain often resolves itself and many find that their pain improves with simple treatments.

Background Information and Anatomy

The most common type of low-back pain originates in the lower back and travels through the buttock and down the leg. This is known as lumbosacral radicular pain or sciatica.

Sciatica is most likely to develop around age 40 or 50. Sciatica causes the sensation of pins and needles, a decrease in motor function, or difficulty performing certain movements that decrease one’s activity level and quality of life.

To understand the cause of sciatica, it is important to understand the anatomy of the spine. The spinal cord can be divided into segments—or levels—according to the nerve roots that branch off. Nerve roots run through the bony spinal canal. In the lumbar and sacrum regions of the spine, a pair of nerve roots exits from the spine at each level.

Spinal stenosis, a narrowing of the disk space, and disk protrusion (also known as a herniated disk) can cause pinching, irritation, and inflammation of the nerve root(s). As a result, people with one or more of these conditions experience low-back pain that can travel to their legs.

To better understand the cause of a patient’s back pain, physicians will perform a physical examination and offer diagnostic tests, such as magnetic resonance imaging (MRI) and electromyography (EMG). The information gathered helps physicians determine the extent of the nerve damage, source of the pain, and determine a plan for managing pain.

Treatment options include lifestyle changes, physical therapy, oral anti-inflammatory or steroid medications, and epidural steroid injections (ESIs). There are several methods for delivering ESIs, including:

• Interlaminar ESI: An ESI delivered through the back of the spine in the space between two vertebrae and delivering the steroid over a wider area
• Transforaminal ESI (TFESI): An ESI delivered into the opening at the side of the spine where a nerve root exits the spinal cord, allowing for more concentrated delivery to a specific nerve (TFESIs are also referred to ask “nerve blocks.”)
  • A single-level TFESI targets the nerve roots that lie across a particular level of the spine causing pain
  • A two-level TFESI (or multilevel TFESI) targets two levels of the spine causing pain.

Read more about ESIs.

In the August 2015 issue of PM&R Journal, three physicians shared differing opinions about single- versus two-level transforaminal epidural steroid injection for alleviating lumbosacral radicular pain. A patient’s case is presented here, followed by a debate as to the best treatment plan. Drs Michael Furman and Nicholas Weber advocate for a 2-level TFESI, while Dr. Steven Cohen asserts that a 1-level TFESI is sufficient.

Patient Case

Matthew, a 58-year-old man, has been experiencing low-back pain for the last 12 weeks. The pain spreads to his groin, right buttock, and entire leg, causing tingling and numbness.

During Matthew’s physical examination, the physician finds that he experiences pain when he raises his straight right leg. Matthew has full range of motion of his hip, with no pain, and his sensory and motor examination results are normal. However, his knee and Achilles reflexes are worse than normal.

An MRI of his low back indicates mild to moderate stenosis at the L4-L5 and L5-S1 region of his spine, as well as a herniated disk at L5-S1 that is pressing the right S1 nerve. An EMG of his right leg was normal and showed no evidence of nerve damage.

After a trial of physical therapy and oral anti-inflammatory medications, Matthew received an interlaminar ESI that provided significant improvement for 4 to 5 days. He is now frustrated that the pain has returned and requested one more injection before considering surgery.

Steven Cohen, MD, Offers His Opinions and Proposed Treatment Plan

Before examining Matthew’s specific treatment plan, let’s look at the big picture. Back pain is increasingly common. An estimated 9 million ESIs are performed annually in the United States alone, [1] which means that this is the most common procedure performed at pain management clinics.

We are seeing negative consequences to the high prevalence of ESIs, as the rates of back pain, expenditures, disability rates, and spine surgery [2-7] have increased steadily. In short, there are significant costs and risks to ESIs, which warrant closer study.

The Food and Drug Administration recently held a panel examining the efficacy of ESIs. Medicare and Medicaid have reduced reimbursement for these procedures sharply. The pain medicine community is reevaluating how we can limit the number of ESIs given and administer them only to the patients who will benefit from them.

The results of a systematic literature review [8] and the guidelines espoused by multiple organizations, including the American Academy of Physical Medicine and Rehabilitation, conclude that no evidence exists to support routinely performing multiple injections [9-11].

We as a profession must find the courage to exercise self-restraint in selecting patients to receive ESIs and use the available evidence to determine the proper treatment plan and intervention. We must educate patients that ESIs typically provide relief for less than a few months. Lifestyle changes and physical therapy must be the cornerstone to any plan for managing back pain, not recurring injections.

Matthew received an interlaminar ESI, which provided very short-term relief. A TFESI is an available option now, but what is known about TFESIs? Randomized, controlled trials have shown that single-level TFESIs are effective. Multilevel TFESIs, however, have not been studied in this same way, so there it’s not certain that they are effective. Also, TFESIs administered to the lower back (both single-level and multilevel) carry a risk for catastrophic complications, including death and paralysis [7]. Due to this risk, TFESIs should be administered judiciously.

To improve Matthew’s quality of life, I believe that we as physicians should treat his symptoms. He experiences pain in his thigh, groin, and buttock, which may come from degenerated disks, facet joints, or muscles. Unfortunately, Matthew’s MRI

does not clearly indicate which nerve root levels are damaged and causing this pain.

His radiculopathy may or may not be the result of damage to one or more spinal nerve root levels. Multilevel disease is common, occurring in approximately 40% of people with radiculopathy [13] and even more among his age demographic.

Multilevel TFESIs are intended to treat multilevel disease, but studies have shown that a well-placed single-level TFESI spreads the injectate across 2 different spinal levels, effectively achieving this goal.

Studies also indicate that higher dosages of steroids do not improve treatment results [17,18]. In fact, a randomized controlled trial by Kang et al [18] comparing different doses of steroids of TFESI found that 10 mg of particulate steroid (triamcinolone) may provide maximal benefit [18].

For Matthew—and the vast majority of back pain patients—I recommend treating in an incremental fashion, starting with conservative options and progressing to more invasive interventions.

There is more evidence supporting the efficacy of single-level TFESIs than multilevel TFESIs. It is also the more conservative option. For these reasons, I believe the best course of action is to administer Matthew a single-level TFESI.

References

1. Manchikanti L, Falco FJ, Singh V, et al. Utilization of interventional techniques in managing chronic pain in the Medicare population: Analysis of growth patterns from 2000 to 2011. Pain Physician 2012; 15:E969-E982.
2. Freburger JK, Homes GM, Agans RP, et al. The rising prevalence of chronic low back pain. Arch Intern Med 2009;169:251-258.
3. Smith M, Davis MA, Stano M, Whedon JM. Aging baby boomers and the rising cost of chronic back pain: Secular trend analysis of longitudinal medical expenditures panel survey data for years to 2000 to 2007. J Manipulative Physiol Ther 2013;36:2-11.
4. Driscoll T, Jacklyn G, Orchard J, et al. The global burden of occupationally related low back pain: estimates from the Global Burden of Disease 2010 study. Ann Rheum Dis 2014;3:975-981.
5. Iezzoni LI, Kurtz SG, Rao SR. Trends in U.S. adult chronic disability rates over time. Disabil Health J 2014;7:402-412.
6. Deyo RA, Mirza SK. Trends and variations in the use of spine surgery. Clin Orthop Relat Res 2006;443:13146.
7. U.S. Food and Drug Administration. Epidural steroid injections (ESI) and the risk of serious neurologic adverse reactions. Released October 28, 2014, in preparation for the Anesthetic and Analgesic Drug Products Advisory Committee Meeting on November 24-25, 2014. Available at: http://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/Drugs/Anesthetic AndAnalgesicDrugProductsAdvisoryCommittee/UCM422692.pdf. Accessed July 6, 2015.
8. Novak S, Nemeth W. The basis for recommending repeating epidural steroid injections for radicular low back pain: A literature review. Arch Phys Med Rehabil 2008;89:543-552.
9. American Academy of Physical Medicine and Rehabilitation. Educational guidelines for interventional spinal procedures. Updated October 2008. Available at: http://www.aapmr.org/practice/guidelines/Documents/edguidelines.pdf. Accessed July 6, 2015.
10. Bogduk N. Practice Guidelines for Spinal Diagnostic and Treatment Procedures. San Francisco, CA: International Spinal Intervention Society; 2004.
11. Manchikanti L, Boswell M, Singh V, et al. Comprehensive evidence-based guidelines for interventional techniques in the management of chronic spinal pain. Pain Physician 2009;12:699-802.
12. Murthy NS, Geske JR, Shelerud RA, et al. The effectiveness of repeat lumbar transforaminal epidural steroid injections. Pain Med 2014;15:1686-1694.
13. Czyrny JJ, Lawrence J. The importance of paraspinal muscle EMG in cervical and lumbosacral radiculopathy: Review of 100 cases. Electromyogr Clin Neurophysiol 1996;36:503-508.
14. Jarvik JG, Deyo RA. Diagnostic evaluation of low back pain with emphasis on imaging. Ann Intern Med 2002;137:586-597.
15. Cohen SP, Gupta A, Strassels SA, et al. Does MRI affect outcomes in patients with lumbosacral radiculopathy referred for epidural steroid injections? A randomized, double-blind, controlled study. Arch Intern Med 2012;172:134-142.
16. Botwin K, Natalicchio J, Brown LA. Epidurography contrast patterns with fluoroscopic guided lumbar transforaminal epidural injections: A prospective evaluation. Pain Physician 2004;7:211-215.
17. Owlia M, Salimzadeh A, Alishiri G, Haghighi A. Comparison of two doses of corticosteroid in epidural steroid injection for lumbar radicular pain. Singapore Med J 2007;48:241-245.
18. Kang S, Hwang B, Son H, et al. The dosages of corticosteroid in transforaminal epidural steroid injections for lumbar radicular pain due to a herniated disc. Pain Physician 2011;14: 361-370.
19. Deyo RA, Gray DT, Kreuter W, Mirza S, Martin BI. United States trends in lumbar fusion surgery for degenerative conditions. Spine (Phila Pa 1976) 2005;30:1441-1445.
20. Chou R, Qaseem A, Owens DK, Shekelle P. Clinical Guidelines Committee of the American College of Physicians. Diagnostic imaging for low back pain: Advice for high-value health care from the American College of Physicians. Ann Intern Med 2011; 154:181-189

Michael B Furman, MD, MS, and Nicholas H Weber, DO, Respond

When treating back pain, it is very difficult to determine the exact origin of the pain. Physicians cannot diagnose using either symptoms or imaging (MRIs and EMGs) alone; we must assess both.

Matthew’s case illustrates this challenge well. It is difficult to find the area of the spine causing pain from his physical examination. The positive right straight leg raise test suggests that the pain may originate from multiple nerve root levels.

Likewise, it is difficult to draw specific conclusions from his MRI. It does, however, indicate that the pain originates in the right lower levels of his spine. Matthew’s diagnostic test results show that he does not have actual nerve damage. This suggests that he has a good prognosis for recovery with appropriate treatment.

It is also helpful to evaluate Matthew’s response to previous pain treatment. The interlaminar ESI provided some relief, which suggests that the cause of his pain is in the lower spine. It does not, however, help us determine the exact nerve root level.

Considering all these factors, our first choice is to administer a diagnostic TFEI to better determine the exact location of his source of pain [5]. Matthew’s response to this will help us administer another TFESI to the exact source of his pain.

However, Matthew is requesting that we limit our plan to only one more procedure before seeking surgery, which he perceives as the definitive treatment. Since he is only willing to pursue one more procedure, we want to administer an ESI with the greatest chance of alleviating his pain.

A 2-level TFESI will deliver medication to 2 segments of his spine, increasing the likelihood of delivering therapeutic effects. We suggest a 2-level TFESI at L4 and L5 segments.

References

1. Wolff AP, Groen GJ, Crul BJ. Diagnostic lumbosacral segmental nerve blocks with local anesthetics: A prospective double-blind study on the variability and interpretation of segmental effects. Reg Anesth Pain Med 2001;26:147-155.
2. Slipman CW, Plastaras CT, Palmitier RA, Huston CW, Sterenfeld EB. Symptom provocation of fluoroscopically guided cervical nerve root stimulation. Are dynatomal maps identical to dermatomal maps? Spine 1998;23:2235-2242.
3. Boden SD, Davis DO, Dina TS, Patronas NJ, Wiesel SW. Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. A prospective investigation. J Bone Joint Surg Am 1990;72:403-408.
4. Botwin KP, Natalicchio J, Hanna A. Fluoroscopic guided lumbar interlaminar epidural injections: A prospective evaluation of epidurography contrast patterns and anatomical review of the epidural space. Pain Physician 2004;7:77-80.
5. Bogduk N, ed. Practice Guidelines for Spinal Diagnostic and Treatment Procedures. 2nd ed. San Francisco, CA: International Spine Intervention Society; 2013.
6. Furman MB, Butler SP, Kim RE, et al. Injectate volumes needed to reach specific landmarks in S1 transforaminal epidural injections. Pain Med 2012;13:1265-1274.
7. Furman MB, Mehta AR, Kim RE, et al. Injectate volumes needed to reach specific landmarks in lumbar transforaminal epidural injections. PM R 2010;2:625-635.
8. Furman MB, Lee TS, Mehta A, Simon JI, Cano WG. Contrast flow selectivity during transforaminal lumbosacral epidural steroid injections. Pain Physician 2008;11:855-861.

Steven P Cohen, MD, Rebuts

I disagree with Drs Michael Furman’s and Nicholas Weber’s assertion that Matthew’s positive straight leg raising test indicates that multiple nerve roots are causing his pain. This may or may not be true [1], but it is not certain. I believe that this test indicates radiculopathy at L5 or S1. In this case, a well-positioned single-level TFESI should cover both of these areas.

Dr Furman has previously researched and concluded that TFESIs often spread to multiple nerve root levels [2-4]. In the most relevant of these studies, he found that even with as little as 1 mL of injectate, a single-level TFESI spreads medication to an adjacent nerve root(s) two-thirds of the time. With 2 mL of injectate, an injection spreads to an adjacent nerve root in 87% of cases [4].

Drs Furman and Weber cite Matthew’s statement that he is willing to try “one more injection before surgery” as a reason to perform a 2-level injection. I believe that Matthew would benefit more from better education regarding the long-term risks and benefits of surgery, particularly the common misconception that surgery provides a permanent solution [9].

The argument that a 2-level injection is more likely to deliver steroids to pain source may or may not be true, but this notion is irrelevant because compelling evidence shows that higher local concentrations of steroids do not improve outcomes. Among the 5 studies that compared different dosages of steroids, none has found that higher dosages result in better outcomes [10-14].

The fact that Matthew obtained significant, albeit short-term, relief after the injection suggests that the interlaminar ESI injectate reached the diseased area(s). This supports my belief that administering a single-level TFESI is the best course of action.

The practice of performing a series of injections without regard to patient response is eschewed by every major pain organization, including guidelines published by the American Academy of Physical Medicine & Rehabilitation [15]. In Matthew’s case, performing multiple injections is unnecessary and potentially harmful.

The principal reason that ESIs have come under such scrutiny is that pain medicine specialists often perform unnecessary procedures, which translates into a higher failure rate and more complications. In Matthew’s case, one thing that we know for certain is that performing multiple injections will increase risks without substantially improving the likelihood of success.

References

1. Rebain R, Baxter GD, McDonough S. A systematic review of the passive straight leg raising test as a diagnostic aid for low back pain(1989 to 2000). Spine (Phila Pa 1976) 2002;27:E388-E395.
2. Furman MB, Butler SP, Kim RE, et al. Injectate volumes needed to reach specific landmarks in S1 transforaminal epidural injections. Pain Med 2012;13:1265-1274.
3. Furman MB, Mehta AR, Kim RE, et al. Injectate volumes needed to reach specific landmarks in lumbar transforaminal epidural injections. PM R 2010;2:625-635.
4. Furman MB, Lee TS, Mehta A, Simon JI, Cano WG. Contrast flows electivity during transforaminal lumbosacral epidural steroid injections. Pain Physician 2008;11:855-861.
5. Plastaras CT, Joshi AB. The electrodiagnostic evaluation of radiculopathy. Phys Med Rehabil Clin N Am 2011;22:59-74.
6. Mondelli M, Aretini A, Arrigucci U, Ginanneschi F, Greco G,Sicurelli F. Clinical findings and electrodiagnostic testing in 108consecutive cases of lumbosacral radiculopathy due to herniated disc. Neurophysiol Clin 2013;43:205-215.
7. Cosgrove JL, Bertolet M, Chase SL, Cosgrove GK. Epidural steroid injections in the treatment of lumbar spinal stenosis efficacy and predictability of successful response. Am J Phys Med Rehabil 2011;90:1050-1055.
8. Marchetti J, Verma-Kurvari S, Patel N, Ohnmeiss DD. Are electro-diagnostic study findings related to a patient’s response to epidural steroid injection? PM R 2010;2:1016-1020.
9. Bruggeman AJ, Decker RC. Surgical treatment and outcomes of lumbar radiculopathy. Phys Med Rehabil Clin N Am 2011;22:161-177.
10. Kim WH, Sim WS, Shin BS, et al. Effects of two different doses of epidural steroid on blood glucose levels and pain control in patients with diabetes mellitus. Pain Physician 2013;16:557-568.
11. Whynes DK, McCahon RA, Ravenscroft A, et al. Cost effectiveness of epidural steroid injections to manage chronic lower back pain. BMC Anesthesiol 2012;12:26.
12. Kang SS, Hwang BM, Son HJ, et al. The dosages of corticosteroid in transforaminal epidural steroid injections for lumbar radicular pain due to a herniated disc. Pain Physician 2011;14:361-370.
13. Owlia M, Salimzadeh A, Alishiri G, Haghighi A. Comparison of two doses of corticosteroid in epidural steroid injection for lumbar radicular pain. Singapore Med J 2007;48:241-245.
14. Cohen SP, Jamison D, Bicket M, Wilkinson I, Rathmell JN. Epidural steroids: A comprehensive, evidence-based review. Reg Anesth Pain Med 2013;38:175-200.
15. American Academy of Physical Medicine and Rehabilitation. Educational guidelines for interventional spinal procedures. Updated October 2008. Available at: http://www.aapmr.org/practice/guidelines/Documents/edguidelines.pdf. Accessed July6, 2015

Michael B Furman, MD, MS, and Nicholas H Weber, DO, Rebut

We still contend that a 2-level TFESI is the most effective procedure for Matthew. We agree with Dr Cohen that a 1-level injection may cover “2 different levels” [1-4]. We disagree, however, with his citing 2 limited studies [5,6] as an argument against delivering the steroid over the affected areas to optimize outcomes, stating that higher dosages of steroids do not improve treatment results.

More relevant, we know of no studies that specifically confirm or refute whether placing the needle at the site of disease will be more effective. However, this does not dissuade us from our thesis: it is logical to concentrate the medication where it will be most effective.

Dr Cohen focuses on multiple injections as a point of contention. The utility, or lack thereof, for repeating subsequent injections does not address the question at hand. In the given scenario, we have specifically been asked to address which single-visit treatment we recommend for this patient with nonspecific imaging and clinical findings: either a 1- or a 2-level TFESI.

We believe a 2-level TFESI is the best treatment option for Matthew right now, without any consideration as to the best course of action if his pain returns in the future. If his symptoms return after achieving significant functional benefit for a substantial period from an initial injection, we would repeat the same 2-level TFESI again. Although only single level TFESIs were investigated, the data from Murthy et al [7] suggest that repeating successful TFESIs yields nearly the same benefit as that of the initial injection.

In summary, we firmly stand by our original position. We suggest the 2-level injection because this is most likely our “last shot” at improving Matthew’s condition and quality of life. This option allows us to concentrate the medication where it will be most effective. If that approach does not provide Matthew with significant pain relief, we can comfortably state that we have no further steroid injections to offer.

References

1. Botwin K, Natalicchio J, Brown LA. Epidurography contrast patterns with fluoroscopic guided lumbar transforaminal epidural injections: A prospective evaluation. Pain Physician 2004;7:211-215.
2. Furman MB, Butler SP, Kim RE, et al. Injectate volumes needed to reach specific landmarks in S1 transforaminal epidural injections. Pain Med 2012;13:1265-1274.
3. Furman MB, Mehta AR, Kim RE, et al. Injectate volumes needed to reach specific landmarks in lumbar transforaminal epidural injections. PM R 2010;2:625-635.
4. Furman MB, Lee TS, Mehta A, Simon JI, Cano WG. Contrast flow selectivity during transforaminal lumbosacral epidural steroid injections. Pain Physician 2008;11:855-861.
5. Kang S, Hwang B, Son H, et al. The dosages of corticosteroid in transforaminal epidural steroid injections for lumbar radicular pain due to a herniated disc. Pain Physician 2011;14:361-370.
6. Owlia M, Salimzadeh A, Alishiri G, Haghighi A. Comparison of two doses of corticosteroid in epidural steroid injection for lumbar radicular pain. Singapore Med J 2007;48:241-245.
7. Murthy NS, Geske JR, Shelerud RA, et al. Effectiveness of repeat lumbar TFESIs. Pain Med 2014;15:1686-1694.

Keywords

Dermatome: An area of skin that receives signals from one spinal nerve.

Herniated nucleus pulposus: A herniated or slipped disk, also referred to as lumbar radiculopathy.

Lumbar spine: The part of the spine comprised of five vertebral bodies that extend from the lower chest to the bottom of the spine, L1 to L5.

Lumbosacral: Of or relating to or near the small of the back and the back part of the pelvis between the hips, the lower back.

Neuropraxia: A disorder of the peripheral nervous system in which there is a temporary loss of motor and sensory function.

Radiculopathy: A set of conditions in which one or more do not work properly, resulting in pain, weakness, numbness, or difficulty controlling specific muscles.

Sciatica: A medical condition of pain radiating down the lower back and sometimes the hip and leg.

Spinal nerve: A nerve that carries motor, sensory, and autonomic signals between the spinal cord and the body. There are 31 pairs of spinal nerves, one on each side of the vertebral column.

Spinal stenosis: A narrowing of the open spaces within your spine. This can put pressure on your spinal cord and the nerves that travel through it.

Vertebra: The bones that make up the spinal column. In between each vertebra lies a disk.