Parasagittal Versus Transforaminal Epidural Steroid Injection, a Study of Contrast Flow in the Epidural Space and Clinical Outcomes: An RCT

Abstract Epidural steroid injections are frequently used to treat lumbosacral radicular pain, but the solute spread in the epidural space needs further investigation. This double-blind, randomized study assessed clinical outcomes and contrast spread patterns between the parasagittal interlaminar and transforaminal approaches in 79 adults with low back pain due to herniated or degenerated discs. Participants were randomly assigned to one of two groups: Transforaminal or Parasagittal Interlaminar. All procedures were performed under C-armed fluoroscopic guidance. Contrast spread was evaluated by a separate pain specialist, and clinical outcomes such as analgesia, patient satisfaction, and quality of life were measured at two weeks and one, three, and six months post-treatment. Results showed no statistically significant differences between the two groups in the mean pain intensity at the moment and six months after treatment (p = 0.618, p = 0.484). Comparison of contrast diffusion to the anterior epidural space between the two groups showed no statistically significant differences (P = 0.436). Clinical outcomes were similar between the two groups, but radiation exposure was significantly higher in the transforaminal group. Both approaches had the same rate of contrast flow to the anterior epidural space. However, the parasagittal interlaminar approach resulted in less radiation exposure for patients.