Effect of Timolol vs. a postural orthotic on hand tremor during microsurgery

The efficacy of beta blockers to control hand tremor remains equivocal. This study evaluated the effectiveness of Timolol, as well as a postural orthotic, in reducing movement deviation during a laboratory exercise. Eleven volunteers completed three randomized trials involving administration of Timolol, a placebo, or a postural orthotic. Drug administration was blinded. Each trial consisted of a simulated 2-hr clinical procedure, punctuated by video recordings of the subject's hand motion during a standardized pattern of instrument movement. ECRL EMG activity and digital oxygen perfusion were also measured. Recordings were converted into estimates of linear variance at baseline and 1 and 2 hr. A repeated-measures ANOVA, or the Friedman test, were used to assess significant differences. Movement deviation, EMG activity, and oxygen perfusion were unaffected by the duration of exercise or treatment (P > or = 0.454). We conclude that none of the treatments accorded a significant benefit in allaying hand tremor.