Progress in Management of Essential and Parkinson Disease Tremor with Botulinum Toxin Injections-Established Efficacy and Less Adverse Effects

Abstract

Tremor is a common movement disorder, and in severe cases, often disables the patients. Essential tremor (ET) and Parkinson-related tremor are two of the most common forms encountered. Earlier double blind and placebo-controlled studies had suggested efficacy of BoNT-A injections into the forearm muscles in reducing the hand and forearm tremor in patients with essential tremor (ET). High quality publications over the past two years have established the efficacy of botulinum toxin-A therapy for ET as well as demonstrating probable efficacy of BoNT-A injections in Parkinson disease tremor. These recent publications also describe novel techniques such as the one used in the Yale protocol using EMG screening and a customized approach and the kinematic computerized amplitude analysis of tremor that have substantially reduced the incidence of hand and forearm weakness reported as adverse effects in the previous high quality studies.