Sympathetic Blockade with Botulinum Toxin Tied to Pain Relief in Complex Regional Pain Syndrome: Study

South Korea: Lumbar sympathetic ganglion block using botulinum toxin type A raised the temperature of the affected foot for 3 months in patients with complex regional pain syndrome and also reduced the pain, reveals a recent study. The study was published in the February 2022 issue of the journal Anesthesiology. 

The study was designed to test the hypothesis that botulinum toxin prolongs the duration of a lumbar sympathetic block measured through a sustained increase in skin temperature. Jee Youn Moon, Seoul National University Hospital, Seoul, Republic of Korea, and colleagues performed a randomized, double-blind, controlled trial to examine the clinical outcome of botulinum toxin type A for lumbar sympathetic ganglion block in patients with complex regional pain syndrome.

For this purpose, the researchers conducted lumbar sympathetic ganglion block in patients with lower-extremity complex regional pain syndrome using 75 IU of botulinum toxin type A (botulinum toxin group) and local anesthetic (control group). 

The change in the relative temperature difference on the blocked sole compared with the contralateral sole at 1 postoperative month was the primary outcome. The 3-month changes in relative temperature differences, and the pain intensity changes were the secondary outcomes.