Presented at the 2013 AAPM Annual Meeting « Back

Predicting Epidural Steroid Injection Outcomes with Lab Markers and Imaging Techniques

Monika Y. Patel, MD, monikay.patel@gmail.com¹, Benoy Benny, MD², (1) University of Texas and Baylor College of Medicine, Houston, Texas, (2) Baylor College of Medicine, Houston, Texas

Introduction: This literature review evaluates lab markers and imaging techniques as predictive tools for epidural steroid injection outcomes in treating radicular pain. Methods: A literature search was performed using PubMed database. Each article had a clear definition of radicular pain, and either a lab marker or imaging technique was investigated as a prediction tool for epidural steroid injection outcomes measured by improvement in pain and/or function. Four retrospective articles were included for analysis of imaging techniques, and four prospective articles included for analysis of lab markers. Analysis: Quality evaluation and prognostic accuracy grading were performed based on the 2011 American Academy of Neurology Clinical Practice Guideline Process Manual: Prognostic Accuracy. Results: Level U: Data on prognostic accuracy of imaging for determination of epidural steroid outcome is inadequate and conflicting. Level B IFN-y >10pg/mL is a probable prognostic indicator of greater than 50% reduction of pain per VAS at 3 months after ESI. Level U: Data on fibronectin-aggrecan complex as a prognostic indictor of ESI outcome is inadequate. Level U: Data on hs-CRP as a prognostic indictor of ESI outcome is inadequate and conflicting. Conclusions: Predictive tools for ESI outcome such as nerve root compression grading and inflammatory markers particularly elevated IFN-y within the epidural space seem promising in the future. At this time, future research is needed with a larger sample size, broad spectrum of patients and defined outcome measurements at standardized follow-up time periods before practice recommendations can be made. References: 1) Fish DE, Kobayashi HW, Chang TL, Pharm Q. MRI prediction of therapeutic response to epidural steroid injection in patients with cervical radiculopathy. Am J Phys Med Rehabil. 2009 Mar; 88(3):239-49. 2) Campbell MJ, Carreon LY, Glassman SD, McGinnis MD, Elmlinger BS. Correlation of Spinal Canal Dimensions to Efficacy of Epidural Steroid Injection in Spinal Stenosis. Journal of Spinal Disorders & Techniques. 2007 Apr; 20(2):168-171. 3) Paidin M, Hansen P, McFadden M, Kendall R. Contrast Dispersal Patterns as a Predictor of Clinical Outcome with Transforaminal Epidural Steroid Injection for Lumbar Radiculopathy. PM R. 2011 Nov; 3(11): 1022-7. 4) Golish SR, Hanna LS, Bowser RP, Montesano PX, Carragee EJ, Scuderi GJ. Outcome of lumbar epidural steroid injection is predicted by assay of a complex of fibronectin and aggrecan from epidural lavage. Spine (Phila Pa 1976). 2011 Aug 15; 36(18): 1464-9. 5) Park CH, Lee SH. Prognostic usefulness of high sensitivity C-reactive protein for transforaminal epidural steroid injection in patients with radicular pain. Pain Med. 2011 Feb; 12(2):219-23. 6) Scuderi GJ, Cuellar JM, Cuellar VG, Yeomans DC, Carragee EJ, Angst MS. Epidural interferon gamma-immunoreactivity: a biomarker for lumbar nerve root irritation. Spine (Phila Pa 1976). 2009 Oct 1;34(21):2311-7. 7) Ackerman WE 3rd, Zhang JM. Serum hs-CRP as a useful marker for predicting the efficacy of lumbar epidural steroid injections on pain relief in patients with lumbar disc herniations. The Journal of the Kentucky Medical Association. 2006 Jul; 104(7):295–9 8) Bogduk N, Ghahreman A. Predictors of a Favorable Response to Transforaminal Injection of Steroids in Patients with Lumbar Radicular Pain due to Disk Herniation. Pain Medicine. 2011; 12:871-897. 9) S.West, V.King, T.S.Carey et al. Systems to Rate the Strength of Scientific Evidence, Evidence Report/Technology Assessment No. 47 10) Gronseth, GS. Woodroffe, LM. Getchius, TS. Clinical Practice Guideline Process Manual. 2011 Ed. St. Paul, MN: The American Academy of Neurology.

Funding: None