title: Analysis of Inadvertent Intradiscal Injections during Lumbar Transforaminal Epidural Injection.
abstract: BACKGROUND
  Recently, there have been several case reports and retrospective studies about the incidence of intradiscal (ID) injection during transforaminal epidural steroid injection (TFESI). Inadvertent ID injection is not a rare complication, and it carries the risk of developing diskitis, although there has been no report of diskitis after TFESI. We prospectively evaluated the incidence of inadvertent ID injection during lumbar TFESI and analyzed the contributing factors.
  
  
  METHODS
  Ten patients received 2-level TFESI, and the remaining 229 patients received 1-level TFESI. When successful TFESI was performed, 2 ml of contrast dye was injected under real-time fluoroscopy to check for any inadvertent ID spread. A musculoskeletal radiologist analyzed all magnetic resonance images (MRIs) of patients who demonstrated inadvertent ID injection. When reviewing MRIs, the intervertebral foramen level where ID injection occurred was carefully examined, and any anatomical structure which narrowing the foramen was identified.
  
  
  RESULTS
  Among the 249 TFESI, we identified 6 ID injections; thus, there was an incidence of 2.4%. Four patients had isthmic spondylolisthesis, and the level of spondylolisthesis coincided with the level of ID injection. We further examined the right or left foramen of the spondylolisthesis level and identified the upward migrated disc material that was narrowing the foramen.
  
  
  CONCLUSIONS
  Inadvertent ID injection during TFESI is not infrequent, and pain physicians must pay close attention to the type and location of disc herniation.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Ji Hee
authors.initials: JH
authors.lastname: Hong
authors.affiliation: Department of Radiology, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Sung Mun
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Department of Anesthesiology and Pain Medicine, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Jin Hong
authors.initials: JH
authors.lastname: Bae
keywords: intradiscal injection; spondylolisthesis
references.citation: Reg Anesth Pain Med. 2013 May-Jun;38(3):175-200
references.pmid: 23598728
references.citation: Pain Med. 2014 Mar;15(3):379-85
references.pmid: 24341966
references.citation: Korean J Anesthesiol. 2010 Jan;58(1):104-8
references.pmid: 20498821
references.citation: Reg Anesth Pain Med. 2013 Nov-Dec;38(6):520-5
references.pmid: 24141875
references.citation: Spine (Phila Pa 1976). 2003 Jun 1;28(11):1103-12
references.pmid: 12782976
references.citation: Pain Med. 2013 Aug;14(8):1126-33
references.pmid: 23895182
references.citation: Spine J. 2013 Jun;13(6):706-12
references.pmid: 23541448
references.citation: J Back Musculoskelet Rehabil. 2013;26(2):183-8
references.pmid: 23640320
references.citation: Reg Anesth Pain Med. 2005 Mar-Apr;30(2):163-83
references.pmid: 15765459
references.citation: Spine (Phila Pa 1976). 2009 Oct 1;34(21):2338-45
references.pmid: 19755936
references.citation: Spine J. 2014 Sep 1;14(9):1970-7
references.pmid: 24361346
references.citation: Spine (Phila Pa 1976). 2005 Mar 15;30(6 Suppl):S71-81
references.pmid: 15767890
references.citation: Anesth Analg. 2008 Feb;106(2):638-44, table of contents
references.pmid: 18227326
references.citation: Pain Med. 2008 Sep;9(6):688-94
references.pmid: 18657222
references.citation: Anesth Analg. 2013 Jul;117(1):219-27
references.pmid: 23632053
references.citation: Acta Neurochir (Wien). 2009 Nov;151(11):1445-50
references.pmid: 19499170
references.citation: Anesth Analg. 2010 May 1;110(5):1464-7
references.pmid: 20418306
references.citation: Pain Med. 2010 Dec;11(12):1765-73
references.pmid: 20807341