Author: Erik Verzemnieks, MD Educational Pearls:   Single study in Japan demonstrated possible effectiveness of renal colic trigger point Patients had injection at the area of maximal tenderness on palpation of the flank Compared to a muscle relaxer, injection of local anesthetic at the trigger point had faster time to pain relief and fewer rescue therapies  References Iguchi, M et al. Randomized trial of trigger point injection for renal colic. International Journal of Urology. 2002. 9(9): 475-479