Complex regional pain syndrome-type II, or causalgia, is a severe pain syndrome caused by incomplete nerve injury. It causes significant suffering due to extreme discomfort and functional compromise and it is a challenging syndrome to treat successfully. This article refines the definition of this syndrome and outlines the criteria for its diagnosis. It also includes discussion of the multiple controversial theories regarding its pathogenesis. It reviews the clinical features, the associated complications, and the suggested treatment options for this syndrome, including rehabilitation management. Early diagnosis and prompt therapeutic intervention enhance the potential for successfully relieving the suffering experienced by patients with this pain syndrome.