Maxpedition - Arid Caduceus Patch. Model MXCADUA. The Symbol of Modern Medicine. The Caduceus was born in Greek mythology and formally adopted by the Medical Department of the United States Army in 1902. It was then added to the uniforms of Army medical officers and used as the symbol for modern medicine. This morale patch pays tribute to this historical design. Light green, dark green, and gray. Measures 2.6" x 2.6".