Intradiskal methylene blue treatment for diskogenic low back pain.

Background: Low back pain is a leading cause of pain and disability. The intervertebral disk has been identified as the most common source of chronic low back pain. Although prior treatments directed at intervertebral disks have been disappointing, recent studies show promising improvement of pain and function after a single intradiskal injection of methylene blue.

Objective: To assess changes in pain and function in patients with diskogenic low back pain, diagnosed by diskography, after an intradiskal injection of methylene blue.

Study Design: Prospective trial.

Methods: Patients diagnosed with diskogenic pain by diskography underwent a single treatment of intradiskal injection of methylene blue, determined by prior provocation diskography.

Main Outcome Measures: Pain and function measurements were completed at baseline and 1, 2, and 6 months after treatment. Treatment was considered a categorical success based on a 30% improvement in pain according to a visual analog scale (VAS) and function on the Oswestry Disability Index (ODI). Treatment was considered a categorical failure if less than 30% improvement in pain and function was achieved or if the patient pursued other invasive treatment options during the trial period.

Results: Sixteen patients received the intradiskal methylene blue injection. Eleven patients received a single-level injection, 4 patients received a 2-level injection, and one patient received injections at 3 levels. For the VAS, at 1, 2, and 6 months after the injection, the categorical success rates were 25%, 21%, and 25%, respectively. For the ODI, at 1, 2 and 6 months after the injection, the categorical success rates were 25%, 21%, and 33%, respectively. The overall categorical success rates at 1, 2, and 6 months after the injection were 19%, 21%, and 25%, respectively.

Conclusion: This small trial did not demonstrate overall clinical success of intradiskal methylene blue injection for patients diagnosed with diskogenic pain by diskography.