Pilot Trial of Botulinum Toxin and Occupational Therapy for Writer's Cramp

Study Summary

Objective: Writer s cramp (WC) is a form of focal hand dystonia (FHD). Focal injections of botulinum toxin (BoNT) are the current best therapy. Past studies showed that some types of rehabilitative therapy can be useful. The hypothesis of this study is that BoNT together with a specific type of occupational therapy will be better than BoNT alone for treating these patients. Additionally, studies on WC were hampered by the lack of objective, validated rating scales. In this pilot study, we will assess the value of a new scale compared with older scales. Study population: The study population will consist of 12 WC patients (accrual ceiling of 16). Design: Patients will be randomized so that 6 patients will receive just BoNT therapy and 6 patients will receive BoNT therapy plus occupational therapy. The physical therapy will involve specific exercises of finger movements in the direction opposite to the patient s own dystonic movements, during the writing task. The movements will be isometric against splints made to suit the individual patient. The final outcome will be assessed after 20 weeks of treatment. Patients will be evaluated on several scales, including the writer s cramp rating scale (WCRS) and writer s cramp impairment scale (WCIS), and will also be videotaped. The primary outcome will be based on patient reported subjective scale and the secondary outcomes will be assessed by four blinded raters of the videotapes, done both before and after treatment. Outcome measures: The primary outcome is to show additional improvement from baseline with BoNT therapy plus occupational therapy compared to BoNT alone at 20 weeks using a patient-rated subjective scale. The secondary outcomes are to show improvement in scores of WCRS, WCIS, WCDS, and writing parameters with a new handwriting analysis program. Additionally, the scores obtained from WCRS and WCIS will be compared.

Primary Outcome

A visual analogue scale was used to rate patient's subjective rating of the severity of their writer's cramp at each visit. Patients were asked to mark the location on a 10 centimeter line corresponding to the severity of their writer's cramp. Ratings ranged from "mild" disease severity to "severe" disease severity. The mark was measured on the 10 centimeter line, ranging from 0 to 10. The percent change in the patient rated subject scale was measured at baseline (Visit 1) and 20 weeks (Visit 8)

Interventions

• DRUG BoNT Injections
• PROCEDURE Occupational Therapy