Incobotulinum Toxin-A in Professional Musicians with Focal Task-Specific Dystonia: A Double Blind, Placebo Controlled, Cross-Over Study.

Background: Musician's focal task-specific dystonia is a complex disorder of fine motor control, with incomplete understanding of its etiology. There have been relatively few trials of botulinum toxin in upper limb task-specific dystonia, and prior studies have yielded variable results, leading to skepticism regarding the utility of this approach in elite performers. Methods: We conducted a double-blind, placebo-controlled, randomized, cross-over study of incobotulinum toxin-A in 21 professional musicians with focal upper extremity task-specific dystonia affecting performance on their instrument, using a novel paradigm of initial injections followed by booster injections at two- and four-week intervals. The primary outcome measure was the change in blinded dystonia rating of the active arm by two expert raters using a Clinical Global Impression numeric scale at week 8 compared to enrollment. Findings: 19 men and 2 women with musicians' dystonia were enrolled over a six-year period. Nineteen patients completed the study. Analysis of the primary outcome measure in comparison to baseline revealed a change in dystonia severity of P = 0.04 and an improvement in overall musical performance of P = 0.027. No clinically significant weakness was observed, and neutralizing antibodies to toxin were not found. Interpretation: Despite its small sample size, our study demonstrated a statistically significant benefit of incobotulinum toxin-A injections as a treatment for musicians' task-specific dystonia. Tailoring the use of toxin with booster injections allowed refinement of dosing strategy and outcomes, with benefits that were meaningful to patients clearly visible on videotaped evaluations. In addition to its application to musicians' dystonia, this approach may have relevance to optimize application of botulinum toxin in other forms of focal dystonia such as blepharospasm, cervical dystonia, writer's cramp, and spasmodic dysphonia.

Chronic pain disorders in HIV primary care: clinical characteristics and association with healthcare utilization.

Chronic pain is common in HIV, but incompletely characterized, including its underlying etiologies, its effect on healthcare utilization, and the characteristics of affected patients in the HIV primary care setting. These data are needed to design and justify appropriate clinic-based pain management services. Using a clinical data warehouse, we analyzed one year of data from 638 patients receiving standard-of-care antiretroviral therapy in a large primary care HIV clinic, located in the Harlem neighborhood of New York City. We found that 40% of patients carried one or more chronic pain diagnoses. The most common diagnoses were degenerative musculoskeletal disorders (eg, degenerative spinal disease and osteoarthritis), followed by neuropathic pain and headache disorders. Many patients (16%) had multiple chronic pain diagnoses. Women, older patients, and patients with greater burdens of medical illness, and psychiatric and substance use comorbidities were disproportionately represented among those with chronic pain diagnoses. Controlling for overall health status, HIV patients with chronic pain had greater healthcare utilization including emergency department visits and radiology procedures. In summary, our study demonstrates the high prevalence of chronic pain disorders in the primary care HIV clinic. Colocated interventions for chronic pain in this setting should not only focus on musculoskeletal pain but also account for complex multifaceted pain syndromes, and address the unique biopsychosocial features of this population. Furthermore, because chronic pain is prevalent in HIV and associated with increased healthcare utilization, developing clinic-based pain management programs could be cost-effective.