Influence of needle-insertion depth on successful epidurogram and clinical outcomes in caudal epidural injections : a randomized clinial trial

Abstract

Introduction: A caudal epidural injection (CESI) is a commonly used method to improve symptoms of lumbosacral pain. We compared the achievement of successful epidurogram and patient reported clinical outcomes following a different needle insertion depth during CESI. Materials and Methods: A total of 130 patients who underwent CESI under fluoroscopy was randomly assigned into the two groups: conventional method group (n=65) receiving the caudal injection after advancement of the needle into the sacral canal and alternative method group (n=65) receiving the injection right after penetrating the sacrococcygeal ligament. Epidural filling patterns and vascular uptake during fluoroscopy were determined to verify successful epidural injection. Procedural pain scores were investigated immediately after the procedure. Pain scores and patient global impression of symptom change were evaluated at 1 month follow-up. Results: Assessments were completed by 127 patients (conventional method, n=64; alternative method, n=63). Incidence of intravascular injection was significantly lower in the alternative method group than in the conventional method group (3.2% vs. 20.3%, P=0.005). Procedural pain during needle insertion was significantly lower in the alternative method group (3.7±1.3 vs. 5.3±1.2, P<0.001). Epidural contrast filling patterns were similar in both groups. One-month follow-up pain scores and patient global impression of symptom change were comparable in both groups. Conclusion: Compared with the conventional method, the alternative method for CESI could achieve similar epidural spread and symptom improvement. The alternative technique exhibited clinical benefits of a lower rate of intravascular injection and less procedural pain.