The frequency and significance of 'striatal toe' in parkinsonism

A striatal toe has been defined as an apparent extensor plantar response, without fanning of the toes, in the absence of any other signs suggesting dysfunction of the cortico-spinal tract. Little is known about the frequency and significance of this sign in parkinsonian syndromes. We prospectively examined 62 patients (Parkinson's disease: other akinetic-rigid syndromes=38:24) for the presence or absence of striatal toe and extensor plantar responses, as defined by Babinski. Details of the history, physical findings and investigations previously undertaken were rated and examined for their relevance to the response obtained from the hallux. Of the 62 patients, 17 patients showed an upgoing plantar response, of whom 13 (Parkinson's disease: other akinetic-rigid syndromes=7:6) had striatal toes, either unilateral (10) or bilateral (3). The remaining four patients showed a classical Babinski sign (Parkinson's disease: other akinetic-rigid syndromes=2:2). There was no lateralising relationship between lesions of the basal ganglia found on imaging and the side of the striatal toe, or the side of dyskinesias found at the time of examination. However, there appeared to be a greater frequency of dyskinesias and evidence of lesions involving the basal ganglia on imaging in patients with striatal toes compared with those who showed a plantar response other than upgoing. The possible relevance of these findings is discussed.