Case Series of Methylene Blue Injections for the Treatment of Zygapophysial and Sacroiliac Joint Pain: Results of 5 Cases

Introduction: Shealy is credited with the use of fluoroscopy guided radiofrequency ablation (RFA) for denervation of the lumbar zygapophysial (L-Z) joint in the mid-1970’s. Peng and colleagues described the use of methylene blue (MB) injection for discogenic pain; MB may work through direct neurotoxicity or inhibition of nitric oxide synthesis. We present a retrospective case series of five patients with L-Z or SI joint pain where MB used as an alternative to RFA. Materials and Methods: This is a retrospective case series of five patients who received MB for the chemical neurolysis of either medial or/and lateral branch’s for zygapophysial or SI joint pain. All of the MB blocks were done under fluoroscopic guidance and performed in the same manner as diagnostic medial and lateral branch blocks but with care to consider the medication as neurotoxic in relation to spinal nerves. On average 1cc of 0.05% final concentration MB was injected per nerve or sacral foraminal level. Results: Four of the five patients had significant lasting pain relief. Discussion: Chemical neurolysis has potential to achieve technical success in these refractory cases of spine pain possibly due to spread over a broader area; for this same reason the procedure should be performed carefully under fluoroscopic guidance.