Interscalene blocks for chronic upper extremity pain.

A study of 25 patients was carried out to determine the efficacy of interscalene block (ISB) for the treatment of chronic upper extremity pain. An RSD score was used to categorize these patients. Seventeen of the 25 patients had less pain after ISB, and 14 also had increased range of motion of the affected limb. Patients with reflex sympathetic dystrophy (RSD)/causalgia, as well as other chronic pain conditions, improved. ISB was compared with stellate ganglion block (SGB) in patients undergoing both treatments. ISB seemed to be at least as effective as SGB for treatment of RSD/causalgia and may have some advantages over SGB. The role of somatic and sympathetic blockade is discussed.