Presented at the 2013 AAPM Annual Meeting « Back

Prospective, Randomized, Comparative Study of Intravascular Injection in Lumbar Medial Branch Blocks Using Different Needle Types

Jeeyoun Moon, MD PhD, jymoon0901@gmail.com¹, Hye Young Kim, MD¹, Soo Young Park¹, Woo Seok Sim², (1) Seoul National University Hospital, Seoul, Republic Of Korea, (2) Samsung Medical Center, Seoul, Republic of Korea

Lumbar zygapophysial joint pain accounts for a common degenerative arthropathy, with a prevalence of approximately 10 - 15% among the chronic axial low back pain. It is generally accepted that the only valid method to diagnose lumbar facet joint pain is through local anesthetic blocks of either the facet joints themselves, or more usually the medial branches that innervate them. A recent study which accomplished an investigation of the ideal number of diagnostic medial branch block (MBB) before radiofrequency denervation, was emphasizing a ‘false-negative block’ as an overlooked by-product of confirmatory MBBs. Among the numerous causes for false-negative responses, the failure of the injectate to bathe the target nerve was closely related to intravascular injection. According to the previous studies, intravascular injection in lumbar MBBs ranged from 3.7 to 8%. In an attempt to investigate the relationship between the needle type and the incidence of intravascular injection, we conduct a prospective randomized comparative study dividing patients scheduled to lumbar MBBs into 2 groups; (1) MBB using a 25-guage sharp needle (Quincke needle); and (2) MBB using a 25-guage blunt needle (Whitacre needle). Total 342 levels of MBBs were done under fluoroscopic visualization. Intravascular spread was more frequently observed using a Quincke needle (p = 0.053) with the odds ratio of 3.71 (95% CI 1.19-11.59) as compared with a Whitacre needle. In conclusion, if we perform a lumbar MBB using a blunt needle, less intravascular injection occurs.

Funding: None

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