Correlation between intravascular injection rate, pain intensity, and degree of cervical neural foraminal stenosis during a cervical transforaminal epidural block

Abstract

Purpose: Cervical transforaminal epidural blocks (CTEBs) are useful for the treatment of cervical radicular pain. However, during CTEBs, inadvertent intravascular injection can introduce particulate steroids into the bloodstream, thus leading to serious complications. Moreover, the risk factors associated with intravascular injection during CTEBs have not been identified. Cervical neural foraminal stenosis (CNFS) is a form of neural foraminal narrowing and a common cause of cervical radicular pain. In this study, we aimed to identify whether there is a correlation between the incidence of intravascular injection during CTEB, pain intensity, and the degree of CNFS. Patients and Methods: A total of 126 patients were recruited. The patients were classified into two subgroups (group M and group S) based on the routine cervical T2-weighted axial magnetic resonance imaging (MRI) findings. Group M (n = 63) consisted of moderate CNFS patients, while group S (n = 63) consisted of severe CNFS patients. The occurrence of intravascular injection during CTEB was established using real-time fluoroscopy. The intravascular injection was determined by the spreading of the contrast medium through the vascular channel during the injection. Additionally, pain intensity was scored using a Numeric Rating Scale (NRS) before the procedure and 1 month after the procedure. Results: There was no significant difference in the incidence of intravascular injection during CTEB between group M and group S (41.3% vs 39.7%, respectively; p = 0.99) and in the NRS scores before and 1 month after CTEB. However, both groups showed a significant decrease in the NRS scores at 1 month after the procedure compared with that before the procedure. Conclusion: The degree of CNFS does not affect the incidence of intravascular injection during CTEB. Regardless of whether patients have moderate or severe CNFS, caution should be exercised during CTEB procedures.