Intradiscal injections during transforaminal epidural steroid injections and interlaminar lumbar epidural steroid injections have been reported rarely. In that regard, this retrospective observational report is the first attempt to quantify the overall rate of this complication. A retrospective analysis of 3 years of accrued data (2004-2007) showed that 2412 transforaminal epidural steroid injections were performed at the 2 training institutions (Loyola University Medical Center and Northwestern University/Feinberg School of Medicine). There were 6 intradiscal (annular) injections of contrast, for a rate of 1:402. Over the same interval, 4723 lumbar epidural steroid injections were performed, with 1 intradiscal injection, for a rate of 1:4723.