BTs are a useful treatment in refractory MPS and have shown promise in various superficial neuropathic pain syndromes. Presumably BTs work by breaking the spasm/pain cycle, giving the patient a "window of opportunity" for traditional conservative measures to have a greater beneficial impact, but several studies suggest that a direct antinociceptive effect distinct from any reduction in muscle spasm may be at play. The major benefit of BTs compared with standard therapies is duration of response. BTs cannot be considered a "first line" treatment for any pain application; however, in refractory cases in which nothing else has helped, BTs may offer the patient and physician a chance for improvement and perhaps even cure.