Incidence of intravascular uptake during fluoroscopically guided lumbar disc injections: a prospective observational study.

Background: Although there are many in vivo studies evaluating lumbar disc injections, no studies have described the occurrence of intravascular uptake of contrast on discography. This phenomenon, however, has been well documented for other fluoroscopically-guided, contrast-enhanced spinal injections.

Objectives: To document the phenomenon and incidence of intravascular uptake during fluoroscopically-guided, contrast-enhanced lumbar disc injections.

Design: A prospective, observational, community-based study.

Methods: The incidence of fluoroscopically-confirmed intravascular uptake of contrast material was documented in 160 patients representing a subset of individuals presenting to a small private community hospital for evaluation and treatment of lower back pain. These patients underwent fluoroscopically-guided lumbar disc injections for therapeutic and/or diagnostic purposes.

Results: A total of 280 discs from L1-2 to L5-S1 were studied. The degree of disc degeneration of the evaluated discs was scored using the Adams' scoring criteria for intervertebral disc degeneration. The incidence of intravascular uptake as well as any correlation between stage of disc degeneration and intravascular uptake was statistically evaluated. A total of 40 out of 280 discs (14.3%) demonstrated intravascular uptake. Detection of intravascular uptake usually required real-time fluoroscopy. There was no statistical correlation between the degree of disc degeneration and the incidence of intravascular uptake. No disc infections or other adverse sequelae occurred.

Conclusion: This is the first study, to our knowledge, that addresses the incidence of intravascular uptake during lumbar disc injections in patients with low back pain. The presence of intravascular uptake may have implications both clinically and diagnostically in regards to interpretation of lumbar discography and adverse events related to loss of injected medications into the vascular system.