Diagnosis and treatment of painful muscle syndromes can be a
difficult and frustrating task for any clinician. Typically, the
mainstay of therapy for such conditions is therapeutic exercise,
analgesics, and a tincture of time. Unfortunately, not all patients
respond to this paradigm, and, despite heroic efforts on the part of the
treating clinician, some conditions are refractory to this approach.
Reports
have described the purported effectiveness of using a biologic
neuromuscular blocking agent, botulinum toxin, in the treatment of
painful conditions associated with skeletal muscle. While incompletely
understood and at times controversial, use of botulinum toxin in the
treatment of conditions associated with involuntary muscle contraction,
such as focal dystonia and spasticity, is supported by prospective,
randomized clinical research; however, while the volume of comparable
studies in pain syndromes is growing, the number of clinical randomized
trials is limited. Moreover, not all such reports have demonstrated
clear efficacy of the use of botulinum toxin under all circumstances.
Therefore, in view of our current understanding of the nature of
muscle-induced pain and the paucity of prospective research regarding
neuromuscular blockade and/or inhibition of nociception in such
conditions, critical and careful analysis of the data and opinions
presented in this section is appropriate.
This article provides
general direction and practical details for the clinician considering
botulinum toxin for treatment of pain. Anatomic drawings for injection
localization and dosing information are intended only as general
guidelines; therapy with botulinum toxin always must be individualized,
accounting for the patient's needs and the clinician's expertise. In
addition, information presented should be used as a convenient reference
source, not as a substitute for clinical training in the use of
botulinum toxin.
