Journal de la douleur et du soulagement

Abstrait

Relationship among Analgesic Effects, Radiating Pain, and Radiological Contrast Material Distribution in Lumbosacral Selective Nerve Root Block

Satoko Chiba*, Sayako Tsutsui, Tomofumi Chiba, Hidekazu Watanabe, Noriko Takiguchi, Yuhei Ishikawa, Tomoko Kitamura and Hisashi  

Objectives: We aimed to determine the correlation of radiographic contrast material distribution with selective lumbosacral nerve root block (SLNRB)-induced radiating pain and pain reduction obtained 3 ± 1 hours after SLNRB.

Patients were stratified according to the distribution of contrast material: those in whom nerve fibres were visualised (type 1), those in whom the nerve sheath was visualised (type 2), and those in whom contrast material was distributed around the nerves (type 3).

Materials and methods: The study population comprised 111 patients who had undergonefluoroscopic SLNRB for pain presumed to be arising from lumbar intervertebral disc displacement. Using a numerical rating scale (the scale is an 11 point scale 0=no pain, 10=worst pain possible), patients evaluated pain intensity before and immediately after SLNRB, 3 ± 1 hours after SLNRB, and SLNRB-induced radiating pain.

Results: Median pain score decreased by 2.5, 3.0, and 3.0 in types 1, 2, and 3, respectively, at 3 ± 1 hours after SLNRB, showing no significant intergroup differences. Median radiating pain scores at the time of SLNRB were 9.5, 9.0, and 6.0 in types 1, 2, and 3, respectively, with significant intergroup differences. Most notably, the radiating pain score was significantly greater in types 1 and 2 than in type 3 (P=0.002 and P=0.01, respectively), though there was no significant difference between types 1 and 2.

Discussion: The analgesic effect of SLNRB was similar regardless of radiographic findings and radiating pain intensity, suggesting that severe radiating pain at the time of SLNRB, or contrast distribution types 1 and 2, is not required for SLNRB.