Serious complications following cervical epidural steroid injection are rare. Subdural injection of local anesthetic and steroid represents a rare but potentially life threatening complication. A patient presented with left sided cervical pain radiating into the left upper extremity with motor deficit. MRI showed absent lordosis with a broad left paramedian disc-osteophyte complex impinging the spinal cord at C5-6. During C5-6 transforaminal epidural steroid injection contrast in AP fluoroscopic view demonstrated a subdural contrast pattern. The needle was withdrawn slightly and repositioned. Normal lateral epidural and nerve root contrast pattern was subsequently obtained and injection followed with immediate improvement in radicular symptoms. There were no postoperative complications on subsequent clinic follow-up. The subdural space is a potential space between the arachnoid and dura mater. As the subdural space is larger in the cervical region, there may be an elevated potential for inadvertent subdural injection. Needle placement in the cervical subdural space during transforaminal injection is uncommon. Failure to identify aberrant needle entry within the cervical subdural space may result in life threatening complications. We recommend initial injection of a limited volume of contrast agent to detect inadvertent subdural space placement. 1. Introduction Cervical radiculopathy is a common condition affecting 83 per 100,000 persons each year [1]. The cause varies by patient age with intervertebral disc herniation common in younger persons and spondylosis predominating in the older age group. Cervical spondylosis is present in 75% of patients older than 65 years of age. Both pathologies can produce anatomic stenosis resulting in impingement or compression of nerve roots or spinal cord. Presenting symptoms include cervical pain with or without radiculopathic upper extremity pain, weakness, deep tendon reflex depression, headache, or vertigo. Duration and severity of symptoms directs selection of treatment modality. Common conservative treatment consists of nonsteroidal anti-inflammatory drugs, anticonvulsants, muscle relaxants, and physical therapy. Efficacy of cervical epidural steroid injection for patients unresponsive to conservative treatment has been demonstrated [2–4]. Symptoms refractory to interventional care or demonstrating myelopathic symptoms of spinal cord compression necessitate consideration for surgical intervention. Epidural injection in the cervical spine can be performed by interlaminar or transforaminal approaches. Transforaminal
References
[1]
C. W. Huston, “Cervical epidural steroid injections in the management of cervical radiculitis: interlaminar versus transforaminal. A review,” Current Reviews in Musculoskeletal Medicine, vol. 2, no. 1, pp. 30–42, 2009.
[2]
K. Bush and S. Hillier, “Outcome of cervical radiculopathy treated with periradicular/epidural corticosteroid injections: a prospective study with independent clinical review,” European Spine Journal, vol. 5, no. 5, pp. 319–325, 1996.
[3]
K. Strobel, C. W. A. Pfirrmann, M. Schmid, J. Hodler, N. Boos, and M. Zanetti, “Cervical nerve root blocks: indications and role of MR imaging,” Radiology, vol. 233, no. 1, pp. 87–92, 2004.
[4]
C. M. Bono, G. Ghiselli, T. J. Gilbert et al., “An evidence-based clinical guideline for the diagnosis and treatment of cervical radiculopathy from degenerative disorders,” Spine Journal, vol. 11, no. 1, pp. 64–72, 2011.
[5]
M. K. Schaufele, L. Hatch, and W. Jones, “Interlaminar versus transforaminal epidural injections for the treatment of symptomatic lumbar intervertebral disc herniations,” Pain Physician, vol. 9, no. 4, pp. 361–366, 2006.
[6]
E. Thomas, C. Cyteval, L. Abiad, M. C. Picot, P. Taourel, and F. Blotman, “Efficacy of transforaminal versus interspinous corticosteroid injection in discal radiculalgia—a prospective, randomised, double-blind study,” Clinical Rheumatology, vol. 22, no. 4-5, pp. 299–304, 2003.
[7]
O. Berger, V. Dousset, O. Delmer, V. Pointillart, J. M. Vital, and J. M. Caillé, “Evaluation of CT-guided periganglionic foraminal steroid injections for treatment of radicular pain in patients with foraminal stenosis,” Journal de Radiologie, vol. 80, no. 9, pp. 917–925, 1999.
[8]
R. Derby, S. Lee, B. Kim, Y. Chen, and K. S. Seo, “Complications following cervical epidural steroid injections by expert interventionalists in 2003,” Pain Physician, vol. 7, no. 4, pp. 445–449, 2004.
[9]
R. Baker, P. Dreyfuss, S. Mercer, and N. Bogduk, “Cervical transforaminal injection of corticosteroids into a radicular artery: a possible mechanism for spinal cord injury,” Pain, vol. 103, no. 1-2, pp. 211–215, 2003.
[10]
P. J. A. M. Brouwers, E. J. B. L. Kottink, M. A. M. Simon, and R. L. Prevo, “A cervical anterior spinal artery syndrome after diagnostic blockade of the right C6-nerve root,” Pain, vol. 91, no. 3, pp. 397–399, 2001.
[11]
F. Vandenabeele, J. Creemers, and I. Lambrichts, “Ultrastructure of the human spinal arachnoid mater and dura mater,” Journal of Anatomy, vol. 189, no. 2, pp. 417–430, 1996.
[12]
M. A. Reina, O. D. L. Casacola, A. Lopez, J. A. D. Andres, M. Mora, and A. Fernandez, “The origin of the spinal subdural space: ultrastructure findings,” Anesthesia and Analgesia, vol. 94, no. 4, pp. 991–995, 2002.
[13]
S. Bansal and M. J. Turtle, “Inadvertent subdural spread complicating cervical epidural steroid injection with local anaesthetic agent,” Anaesthesia and Intensive Care, vol. 31, no. 5, pp. 570–572, 2003.
[14]
A. H. Ajar, J. P. Rathmell, and S. K. Mukherji, “The subdural compartment,” Regional Anesthesia and Pain Medicine, vol. 27, no. 1, pp. 72–76, 2002.
[15]
L. J. Lehmann and V. S. Pallares, “Subdural injection of a local anesthetic with steroids: complication of epidural anesthesia,” Southern Medical Journal, vol. 88, no. 4, pp. 467–469, 1995.
[16]
D. Agarwal, M. Mohta, A. Tyagi, and A. K. Sethi, “Subdural block and the anaesthetist,” Anaesthesia and Intensive Care, vol. 38, no. 1, pp. 20–26, 2010.
[17]
C. Collier, “Total spinal or massive subdural block?” Anaesthesia and Intensive Care, vol. 10, no. 1, pp. 92–93, 1982.
[18]
P. V. Scrivani, P. Y. Barthez, R. Léveillé, S. C. Schrader, and S. M. Reed, “Subdural injection of contrast medium during cervical myelography,” Veterinary Radiology and Ultrasound, vol. 38, no. 4, pp. 267–271, 1997.
[19]
W. P. Milants, P. M. Parizel, J. de Moor, I. G. Tobback, and A. M. de Schepper, “Epidural and subdural contrast in myelography and CT myelography,” European Journal of Radiology, vol. 16, no. 2, pp. 147–150, 1993.
[20]
J. Penderis, M. Sullivan, T. Schwarz, and I. R. Griffiths, “Subdural injection of contrast medium as a complication of myelography,” Journal of Small Animal Practice, vol. 40, no. 4, pp. 173–176, 1999.
[21]
G. Malhotra, A. Abbasi, and M. Rhee, “Complications of transforaminal cervical epidural steroid injections,” Spine, vol. 34, no. 7, pp. 731–739, 2009.
