Complex regional pain syndrome (CRPS) is a condition characterized by regional pain, sensory alterations, motor dysfunction, and abnormality in body temperature, sudomotor activation, skin color changes and regional edema which often appears in the extremities after the onset of a noxious event. CRPS is a disabling disorder with an unknown mechanism. We present a CRPS case which is extremely resistant to conventional pharmaceutical and other therapeutic treatments in the left upper limb, which was treated successfully with continuous interscalene brachial plexus block (BPB).