Botulinum toxin treatment in atypical parkinsonian disorders associated with disabling focal dystonia

We investigated the efficacy of botulinum toxin A (BtxA) therapy in patients with atypical parkinsonian disorders (APD) exhibiting different types of disabling focal dystonia unresponsive to oral drug therapy. Eight patients with functionally disabling focal dystonia out of a series of 60 consecutive patients with APDs regularly treated at our outpatient movement disorders clinic were included. Patients were diagnosed according to established criteria and had disabling limb dystonia (n=4) or craniocervical dystonia (n=4) unresponsive to oral pharmacological treatment. Localization and dose of BtxA injections was determined individually based on clinical examination as well as EMG in patients with limb dystonia. BtxA reduced dystonic symptoms in all patients; only one developed a transient local side-effect. BtxA was particularly effective in the long-term treatment (up to 50 months) of blepharospasm associated with progressive supranuclear palsy (PSP). BtxA also alleviated PSP-associated retrocollis and orofacial dystonia with lower lip retraction associated with PSP and multiple system atrophy. BtxA treatment of limb dystonia in corticobasal degeneration (CBD) temporarily improved hand and arm function in early-disease stages while treatment in advanced stages reduced pain, facilitated hygiene and prevented secondary contractures. Limb dystonia was also alleviated by BtxA therapy in one patient with neuronal multisystem degeneration of undetermined cause. The results suggest that BtxA therapy may represent an effective means of alleviating disabling focal dystonia in different APDs. Particularly in early stage APD with disabling limb dystonia local BtxA injections may result in functional improvement.