Neurological Complications Associated with Epidural Steroid Injections

Current Pain and Headache Reports

Volumn 19, Issue 5, 2015, Pages

  Manchikanti, Laxmaiah ^a,b   Hirsch, Joshua A ^c,d  

^a PAIN MANAGEMENT CENTER OF PADUCAH   (United States)

^b University of Louisville School of Medicine   (United States)

^c MASSACHUSETTS GENERAL HOSPITAL   (United States)

^d HARVARD MEDICAL SCHOOL   (United States)

Author keywords

Caudal epidural injections; Cervical transforaminal epidural injections; Epidural steroid injections; Interlaminar epidural injections; Intraarterial injection of steroids; Neurological complications

Indexed keywords

CORTICOSTEROID; STEROID;

ARACHNOIDITIS; DRUG EFFICACY; DRUG FATALITY; FOOD AND DRUG ADMINISTRATION; HEALTH INSURANCE; HUMAN; MEDICAL LIABILITY; MEDICARE; MENINGITIS; NEUROLOGICAL COMPLICATION; PATHOLOGICAL ANATOMY; REVIEW; SPINAL PAIN; ADVERSE EFFECTS; ANIMAL; EPIDURAL DRUG ADMINISTRATION; NERVOUS SYSTEM DISEASES; POSTOPERATIVE COMPLICATIONS; RISK; UNITED STATES;

ANIMALS; HUMANS; INJECTIONS, EPIDURAL; NERVOUS SYSTEM DISEASES; POSTOPERATIVE COMPLICATIONS; RISK; STEROIDS; UNITED STATES; UNITED STATES FOOD AND DRUG ADMINISTRATION;

EID: 84925320996     PISSN: 15313433     EISSN: 15343081     Source Type: Journal    
DOI: 10.1007/s11916-015-0482-3     Document Type: Review

References (98)

1. US Food and Drug Administration. Drug Safety Communications. FDA drug safety communication: FDA requires label changes to warn of rare but serious neurologic problems after epidural corticosteroid injections for pain. www.fda.gov/downloads/Drugs/DrugSafety/UCM394286.pdf.
2. Manchikanti L, Candido KD, Singh V, Gharibo CG, Boswell MV, Benyamin RM, et al. Epidural steroid warning controversy still dogging FDA. Pain Physician. 2014;17:E451–74. This comprehensive review of the epidural steroid warning controversy describes the prevalence of neurological complications mainly with cervical transforaminal epidural injections and occasionally with lumbar transforaminal epidural injections. The manuscript also describes the efficacy and complications of epidural injections by various modes of administration with interlaminar epidural injections as well as caudal epidural injections.
3. Food and Drug Administration. Anesthetic and Analgesic Drug Products Advisory Committee Meeting. November 24–25, 2014. Epidural steroid injections (ESI) and the risk of serious neurologic adverse reactions. www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/Drugs/AnestheticAndAnalgesicDrugProductsAdvisoryCommittee/UCM422692.pdf.
4. Manchikanti L, Falco FJE, Benyamin RM, Gharibo CG, Candido KD, Hirsch JA. Epidural steroid injections safety recommendations by the Multi-Society Pain Workgroup (MPW): more regulations without evidence or clarification. Pain Physician. 2014;17:E575–88.
5. Engel A, King W, MacVicar J. Standards Division of the International Spine Intervention Society. The effectiveness and risks of fluoroscopically guided cervical transforaminal injections of steroids: a systematic review with comprehensive analysis of the published data. Pain Med. 2014;15:386–402. In this comprehensive manuscript the effectiveness and risks of fluoroscopically guided cervical transforaminal injections of steroids is discussed with a systematic review and comprehensive analysis of the published data. The manuscript reports a lack of proven efficacy of cervical transforaminal epidural injections and a clear and high risk of injection of the particulate steroids with a cervical transforaminal approach.
6. Scanlon GC, Moeller-Bertram T, Romanowsky SM, Wallace MS. Cervical transforaminal epidural steroid injections: more dangerous than we think? Spine (Phila Pa 1976). 2007;32:1249–56.
7. Atluri S, Glaser SE, Shah RV, Sudarshan G. Needle position analysis in cases of paralysis from transforaminal epidurals: consider alternative approaches to traditional techniques. Pain Physician. 2013;16:321–34. This manuscript analyzes needle position in cases of paralysis from transforaminal epidurals showing the value of alternate approaches and the lack of reported complications with alternate approaches.
8. Robecchi A, Capra R. Hydrocortisone (compound F); first clinical experiments in the field of rheumatology. Minerva Med. 1952;98:1259–63.
9. Lievre JA, Bloch-Michael H, Pean G. L’hydrocortisone en injection locale. Rev Rhum. 1953;29:310–1.
10. Bogduk N, Brazenor G, Christophidis N, Cherry D, Fraser R, Jenkins J, et al. Epidural use of steroids in the management of back pain. Report of working party on epidural use of steroids in the management of back pain. Canberra: National Health and Medical Research Council; 1994. p. 1–76.
11. Pettit AC, Malani AN. Outbreak of fungal infections associated with contaminated methylprednisolone acetate: an update. Curr Infect Dis Rep. 2015;17:441.
12. US Burden of Disease Collaborators. The state of US health, 1999–2010: burden of diseases, injuries, and risk factors. JAMA. 2013;310:591–608.
13. Institute of Medicine (IOM). Relieving pain in America: a blueprint for transforming prevention, care, education, and research. The National Academies Press, Washington, DC, June 29, 2011. http://www.iom.edu/~/media/Files/Report%20Files/2011/Relieving-Pain-in-America-A-Blueprint-for-Transforming-Prevention-Care-Education-Research/Pain%20Research%202011%20Report%20Brief.pdf.
14. Gaskin DJ, Richard P. The economic costs of pain in the United States. J Pain. 2012;13:715–24.
15. Martin BI, Turner JA, Mirza SK, Lee MJ, Comstock BA, Deyo RA. Trends in health care expenditures, utilization, and health status among US adults with spine problems, 1997–2006. Spine (Phila Pa 1976). 2009;34:2077–84.
16. Freburger JK, Holmes GM, Agans RP, Jackman AM, Darter JD, Wallace AS, et al. The rising prevalence of chronic low back pain. Arch Intern Med. 2009;169:251–8.
17. Manchikanti L, Abdi S, Atluri S, Benyamin RM, Boswell MV, Buenaventura RM, et al. An update of comprehensive evidence-based guidelines for interventional techniques of chronic spinal pain: part II: guidance and recommendations. Pain Physician. 2013;16:S49–S283.
18. Manchikanti L, Hirsch JA. Lessons learned in the abuse of pain relief medication: a focus on health care costs. Expert Rev Neurother. 2013;13:527–44.
19. Manchikanti L, Helm II S, Singh V, Hirsch JA. Accountable interventional pain management: a collaboration among practitioners, patients, payers, and government. Pain Physician. 2013;16:E635–70.
20. Bae HW, Rajaee SS, Kanim LE. Nationwide trends in the surgical management of lumbar spinal stenosis. Spine (Phila Pa 1976). 2013;38:916–26.
21. Kovacs FM, Urrútia G, Alarcón JD. Surgery versus conservative treatment for symptomatic lumbar spinal stenosis: a systematic review of randomized controlled trials. Spine (Phila Pa 1976). 2011;36:E1335-51.
22. Jacobs WC, van Tulder M, Arts M, Rubinstein SM, van Middelkoop M, Ostelo R, et al. Surgery versus conservative management of sciatica due to a lumbar herniated disc: a systematic review. Eur Spine J. 2011;20:513–22.
23. Weinstein JN, Tosteson TD, Lurie JD, Tosteson AN, Hanscom B, Skinner JS, et al. Surgical vs nonoperative treatment for lumbar disk herniation: the Spine Patient Outcomes Research Trial (SPORT): a randomized trial. JAMA. 2006;296:2441–50.
24. Rubinstein SM, van Middelkoop M, Assendelft WJ, de Boer MR, van Tulder MW. Spinal manipulative therapy for chronic low-back pain: an update of a Cochrane review. Spine (Phila Pa 1976). 2011;36:E825-46.
25. Rajaee SS, Bae HW, Kanim LE, Delamarter RB. Spinal fusion in the United States: analysis of trends from 1998 to 2008. Spine (Phila Pa 1976). 2012;37:67–76.
26. Manchikanti L, Atluri S, Candido KD, Boswell MV, Simopoulos TT, Grider JS, et al. Zohydro™ approval by Food and Drug Administration: controversial or frightening? Pain Physician. 2014;17:E437–50.
27. Express Scripts Lab. A nation in pain. Focusing on U.S. Opioid trends for treatment of short-term and longer-term pain. December 2014. http://lab.express-scripts.com/publications/~/media/d48ef3ee579848e7bf3f14af536d7548.ashx.
28. Centers for Disease Control and Prevention. CDC grand rounds: prescription drug overdoses—a U.S. epidemic. MMWR Morb Mortal Wkly Rep. 2012;61:10–3.
29. Manchikanti L, Cash KA, Malla Y, Pampati V, Fellows B. A prospective evaluation of psychotherapeutic and illicit drug use in patients presenting with chronic pain at the time of initial evaluation. Pain Physician. 2013;16:E1–E13.
30. Leavitt SB. NSAID dangers may limit pain-relief options. Pain-topics news/research UPDATES, March 14, 2010. http://updates.pain-topics.org/2010/03/nsaid-dangers-may-limit-pain-relief.html.
31. Moore A, Wiffen P, Kalso E. Antiepileptic drugs for neuropathic pain and fibromyalgia. JAMA. 2014;312:182–3.
32. van Middelkoop M, Rubinstein SM, Kuijpers T, Verhagen AP, Ostelo R, Koes BW, et al. A systematic review on the effectiveness of physical and rehabilitation interventions for chronic nonspecific low back pain. Eur Spine J. 2011;20:19–39.
33. Davis MA, Sirovich BE, Weeks WB. Utilization and expenditures on chiropractic care in the United States from 1997 to 2006. Health Serv Res. 2010;45:748–61.
34. Annual causes of death in the United States. DrugWarFacts.org http://www.drugwarfacts.org/cms/causes_of_Death#sthash.vGhXfKev.dpbs.
35. Thielke SM, Turner JA, Shortreed SM, Saunders K, Leresche L, Campbell CI, et al. Do patient-perceived pros and cons of opioids predict sustained higher-dose use? Clin J Pain. 2014;30:93–101.
36. Pinto RZ, Maher CG, Ferreira ML, Hancock M, Oliveira VC, McLachlan AJ, et al. Epidural corticosteroid injections in the management of sciatica: a systematic review and meta-analysis. Ann Intern Med. 2012;157:865–77.
37. Chou R, Huffman L. Guideline for the evaluation and management of low back pain: evidence review. Glenview: American Pain Society; 2009.
38. Manchikanti L, Benyamin RM, Falco FJ, Kaye AD, Hirsch JA (2015) Do epidural injections provide short- and long-term relief for lumbar disc herniation? A systematic review. Clin Orthop Relat Res. 2014. doi:10.1007/s11999-014-3490-4.
39. Manchikanti L, Falco FJ, Diwan S, Hirsch JA, Smith HS. Cervical radicular pain: the role of interlaminar and transforaminal epidural injections. Curr Pain Headache Rep. 2014;18:389.
40. Manchikanti L, Nampiaparampil DE, Candido KD, Bakshi S, Grider JS, Falco FJE, et al. Do cervical epidural injections provide long-term relief in neck and upper extremity pain? A systematic review. Pain Physician. 2015;18:39–60.
41. Manchikanti L, Nampiaparampil DE, Manchikanti KN, Falco FJE, Singh V, Benyamin RM, Kaye AD, Sehgal N, Soin A, Simopoulos TT, Bakshi S, Gharibo CG, Gilligan CJ, Hirsch JA. Comparison of the efficacy of saline, local anesthetics, and steroids in epidural and facet joint injections for the management of spinal pain: a systematic review of randomized controlled trials. Surg Neurol Int 2015; in press. This comprehensive manuscript compares the efficacy of saline, local anesthetics, and steroids in epidural and facet joint injections for the treatment of spinal pain utilizing randomized controlled trials with rigorous methodologic quality assessment, with results showing no significant difference with epidural injections with or without steroids; however, specific conditions of high inflammation with disc herniation have shown superior results with steroids
42. Bicket M, Gupta A, Brown CH, Cohen SP. Epidural injections for spinal pain: a systematic review and meta-analysis evaluating the “control” injections in randomized controlled trials. Anesthesiology. 2013;119:907–31.
43. Staal JB, de Bie RA, de Vet HC, Hildebrandt J, Nelemans P. Injection therapy for subacute and chronic low back pain: an updated Cochrane review. Spine (Phila Pa 1976). 2009;34:49–59.
44. Macvicar J, King W, Landers MH, Bogduk N. The effectiveness of lumbar transforaminal injection of steroids: a comprehensive review with systematic analysis of the published data. Pain Med. 2013;14:14–28. This manuscript systematically assesses all the available published data including observational studies showing the effectiveness of lumbar transforaminal epidural injection of steroids.
45. Manchikanti L, Candido KD, Kaye AD, Boswell MV, Benyamin RM, Falco FJE, et al. Randomized trial of epidural injections for spinal stenosis published in the New England Journal of Medicine: further confusion without clarification. Pain Physician. 2014;17:E475–88.
46. Friedly JL, Comstock BA, Turner JA, Heagerty PJ, Deyo RA, Sullivan SD, et al. A randomized trial of epidural glucocorticoid injections for spinal stenosis. N Engl J Med. 2014;371:11–21. Highly emphasized manuscript which appears to be a high quality trial has been criticized for its design, analysis of the data, and utilization of statistical parameters to lean towards preformed opinions.
47. Manchikanti L, Datta S, Gupta S, Munglani R, Bryce DA, Ward SP, et al. A critical review of the American Pain Society clinical practice guidelines for interventional techniques: Part 2. Therapeutic interventions. Pain Physician. 2010;13:E215–64.
48. Manchikanti L, Falco FJE, Hirsch JA. Epidural corticosteroid injections in the management of sciatica. Ann Intern Med. 2012;157:865–77. online comment posted March 29, 2013.
49. Iversen T, Solberg TK, Romner B, Wilsgaard T, Twisk J, Anke A, et al. Effect of caudal epidural steroid or saline injection in chronic lumbar radiculopathy: multicentre, blinded, randomised controlled trial. BMJ. 2011;343:d5278.
50. Karppinen J, Malmivaara A, Kurunlahti M, Kyllönen E, Pienimäki T, Nieminen P, et al. Periradicular infiltration for sciatica: a randomized controlled trial. Spine (Phila Pa 1976). 2001;26:1059–67.
51. Carette S, Marcoux S, Truchon R, Grondin C, Gagnon J, Allard Y, et al. A controlled trial of corticosteroid injections into facet joints for chronic low back pain. N Engl J Med. 1991;325:1002–7.
52. Cohen SP, White RL, Kurihara C, Larkin TM, Chang A, Griffith SR, et al. Epidural steroids, etanercept, or saline in subacute sciatica: a multicenter, randomized trial. Ann Intern Med. 2012;156:551–9.
53. Cohen SP, Hayek S, Semenov Y, Pasquina PF, White RL, Veizi E, et al. Epidural steroid injections, conservative treatment, or combination treatment for cervical radicular pain: a multicenter, randomized, comparative-effectiveness study. Anesthesiology. 2014;121:1045–55.
54. Manchikanti L, Cash KA, McManus CD, Pampati V, Fellows B. Results of 2-year follow-up of a randomized, double-blind, controlled trial of fluoroscopic caudal epidural injections in central spinal stenosis. Pain Physician. 2012;15:371–84.
55. Manchikanti L, Cash KA, McManus CD, Pampati V. Fluoroscopic caudal epidural injections in managing chronic axial low back pain without disc herniation, radiculitis or facet joint pain. J Pain Res. 2012;5:381–90.
56. Manchikanti L, Singh V, Cash KA, Pampati V, Datta S. Fluoroscopic caudal epidural injections in managing post lumbar surgery syndrome: two-year results of a randomized, double-blind, active-control trial. Int J Med Sci. 2012;9:582–91.
57. Dashfield A, Taylor M, Cleaver J, Farrow D. Comparison of caudal steroid epidural with targeted steroid placement during spinal endoscopy for chronic sciatica: a prospective, randomized, double-blind trial. Br J Anaesth. 2005;94:514–9.
58. Ghahreman A, Ferch R, Bogduk N. The efficacy of transforaminal injection of steroids for the treatment of lumbar radicular pain. Pain Med. 2010;11:1149–68.
59. Tafazal S, Ng L, Chaudhary N, Sell P. Corticosteroids in peri-radicular infiltration for radicular pain: a randomised double blind controlled trial: one year results and subgroup analysis. Eur Spine J. 2009;18:1220–5.
60. Manchikanti L, Cash KA, Pampati V, Falco FJE. Transforaminal epidural injections in chronic lumbar disc herniation: a randomized, double-blind, active-control trial. Pain Physician. 2014;17:E489–501.
61. Manchikanti L, Singh V, Cash KA, Pampati V, Falco FJE. A randomized, double-blind, active-control trial of the effectiveness of lumbar interlaminar epidural injections in disc herniation. Pain Physician. 2014;17:E61–74.
62. Amr YM. Effect of addition of epidural ketamine to steroid in lumbar radiculitis: one-year follow-up. Pain Physician. 2011;14:475–81.
63. Manchikanti L, Cash KA, McManus CD, Damron KS, Pampati V, Falco FJE. A randomized, double-blind controlled trial of lumbar interlaminar epidural injections in central spinal stenosis: 2-year follow-up. Pain Physician. 2015;18:79–92.
64. Manchikanti L, Cash KA, McManus CD, Pampati V, Benyamin RM. A randomized, double-blind, active-controlled trial of fluoroscopic lumbar interlaminar epidural injections in chronic axial or discogenic low back pain: results of a 2-year follow-up. Pain Physician. 2013;16:E491–504.
65. Manchikanti L, Cash KA, Pampati V, Wargo BW, Malla Y. A randomized, double-blind, active control trial of fluoroscopic cervical interlaminar epidural injections in chronic pain of cervical disc herniation: results of a 2-year follow-up. Pain Physician. 2013;16:465–78.
66. Manchikanti L, Cash KA, Pampati V, Malla Y. Two-year follow-up results of fluoroscopic cervical epidural injections in chronic axial or discogenic neck pain: a randomized, double-blind, controlled trial. Int J Med Sci. 2014;11:309–20.
67. Manchikanti L, Malla Y, Cash KA, McManus CD, Pampati V. Fluoroscopic epidural injections in cervical spinal stenosis: preliminary results of a randomized, double-blind, active control trial. Pain Physician. 2012;15:E59–70.
68. Manchikanti L, Malla Y, Cash KA, McManus CD, Pampati V. Fluoroscopic cervical interlaminar epidural injections in managing chronic pain of cervical post-surgery syndrome: preliminary results of a randomized, double-blind active control trial. Pain Physician. 2012;15:13–26.
69. Manchikanti L, Singh V, Cash KA, Pampati V, Damron KS, Boswell MV. Effect of fluoroscopically guided caudal epidural steroid or local anesthetic injections in the treatment of lumbar disc herniation and radiculitis: a randomized, controlled, double blind trial with a two-year follow-up. Pain Physician. 2012;15:273–86.
70. Manchikanti L, Cash KA, McManus CD, Pampati V, Benyamin RM. Thoracic interlaminar epidural injections in managing chronic thoracic pain: a randomized, double-blind, controlled trial with a 2-year follow-up. Pain Physician. 2014;17:E327–38.
71. Ng L, Chaudhary N, Sell P. The efficacy of corticosteroids in periradicular infiltration for chronic radicular pain: a randomized, double-blind, controlled trial. Spine (Phila Pa 1976). 2005;30:857–62.
72. Riew KD, Yin Y, Gilula L, Bridwell KH, Lenke LG, Lauryssen C, et al. The effect of nerve-root injections on the need for operative treatment of lumbar radicular pain: a prospective, randomized, controlled, double-blind study. J Bone Joint Surg Am. 2000;82:1589–93.
73. Kim D, Brown J. Efficacy and safety of lumbar epidural dexamethasone versus methylprednisolone in the treatment of lumbar radiculopathy: a comparison of soluble versus particulate steroids. Clin J Pain. 2011;27:518–22.
74. Abram SE, O’Connor TC. Complications associated with epidural steroid injections. Reg Anesth. 1996;21:149–62.
75. Manchikanti L, Falco FJE, Benyamin RM, Caraway DL, Helm II S, Wargo BW, et al. Assessment of infection control practices for interventional techniques: a best evidence synthesis of safe injection practices and use of single-dose medication vials. Pain Physician. 2012;15:E573–614.
76. Manchikanti L, Malla Y, Wargo BW, Cash KA, Pampati V, Fellows B. A prospective evaluation of complications of 10,000 fluoroscopically directed epidural injections. Pain Physician. 2012;15:131–40.
77. Epstein NE. The risks of epidural and transforaminal steroid injections in the spine: commentary and a comprehensive review of the literature. Surg Neurol Int. 2013;4:S74–93.
78. Rathmell JP, Michna E, Fitzgibbon DR, Stephens LS, Posner KL, Domino KB. Injury and liability associated with cervical procedures for chronic pain. Anesthesiology. 2011;114:918–26.
79. Hindman BJ, Palecek JP, Posner KL, Traynelis VC, Lee LA, Sawin PD, et al. Cervical spinal cord, root, and bony spine injuries: a closed claims analysis. Anesthesiology. 2011;114:782–95.
80. Lanier WL, Warner MA. New perioperative cervical injury: medical and legal implications for patients and anesthesia providers. Anesthesiology. 2011;114:729–31.
81. Gaul C, Neundorfer B, Winterholler M. Iatrogenic (para-) spinal abscesses and meningitis following injection therapy for low back pain. Pain. 2005;116:407–10.
82. Metzner J, Posner KL, Lam MS, Domino KB. Closed claims’ analysis. Best Pract Res Clin Anaesthesiol. 2011;25:263–76.
83. Hooten WM, Kinney MO, Huntoon MA. Epidural abscess and meningitis after epidural corticosteroid injection. Mayo Clin Proc. 2004;79:682–6.
84. Fitzgibbon DR, Rathmell JP, Michna E, Stephens LS, Posner KL, Domino KB. Malpractice claims associated with medication management for chronic pain. Anesthesiology. 2010;112:948–56.
85. Shah RV. Paraplegia following thoracic and lumbar transforaminal epidural steroid injections: how relevant is physician negligence? J Neurointerv Surg. 2014;6:166–8.
86. El Abd OH, Amadera JE, Pimentel DC, Pimentel TS. Intravascular flow detection during transforaminal epidural injections: a prospective assessment. Pain Physician. 2014;17:21–7.
87. Gharibo C, Koo C, Chung J, Moroz A. Epidural steroid injections: an update on mechanisms of injury and safety. Reg Anes Pain Manag. 2009;13:266–71.
88. Huntoon MA. Anatomy of the cervical intervertebral foramina: vulnerable arteries and ischemic neurologic injuries after transforaminal epidural injections. Pain. 2005;117:104–11.
89. Rijsdijk M, van Wijck AJ, Kalkman CJ, Yaksh TL. The effects of glucocorticoids on neuropathic pain: a review with emphasis on intrathecal methylprednisolone acetate delivery. Anesth Analg. 2014;118:1097–112.
90. Barros GA, Marques ME, Ganem EM. The effects of intrathecal administration of betamethasone over the dogs’ spinal cord and meninges. Acta Cir Bras. 2007;22:361–5.
91. Kroin JS, Schaefer RB, Penn RD. Chronic intrathecal administration of dexamethasone sodium phosphate: pharmacokinetics and neurotoxicity in an animal model. Neurosurgery. 2000;46:178–82.
92. Latham JM, Fraser RD, Moore RJ, Blumbergs PC, Bogduk N. The pathologic effects of intrathecal betamethasone. Spine (Phila Pa 1976). 1997;22:1558–62.
93. Lima RM, Navarro LH, Carness JM, Barros GA, Marques ME, Solanki D, et al. Clinical and histological effects of the intrathecal administration of methylprednisolone in dogs. Pain Physician. 2010;13:493–501.
94. Kotani N, Kushikata T, Hashimoto H, Kimura F, Muraoka M, Yodono M, et al. Intrathecal methylprednisolone for intractable postherpetic neuralgia. N Engl J Med. 2000;343:1514–9.
95. Kimdo W, Han KR, Kim C, Chae YJ. Intravascular flow patterns in transforaminal epidural injections: a comparative study of the cervical and lumbar vertebral segments. Anesth Analg. 2009;109:233–9.
96. Rathmell JP. Toward improving the safety of transforaminal injection. Anesth Analg. 2009;109:8–10.
97. Tiso RL, Cutler T, Catania JA, Whalen K. Adverse central nervous system sequelae after selective transforaminal block: the role of corticosteroids. Spine J. 2004;4:468–74.
98. Dawley JD, Moeller-Bertram T, Wallace MS, Patel PM. Intra-arterial injection in the rat brain: evaluation of steroids used for transforaminal epidurals. Spine (Phila Pa 1976). 2009;34:1638–43.