Parietal motor syndrome: A clinical description in 32 patients in the acute phase of pure parietal strokes studied prospectively

We prospectively studied motor symptoms in 32 patients with CT- or MRI-prov en acute pure parietal stroke. A transient, mild, 'pseudoparesis' of the ha nd (90%), was noted, improved by visual attention and prompting, associated with non-awareness of muscle power (53%), transient soft pyramidal signs ( 50%), unilateral akinesia (100%) and motor hemineglect (37%) in non-dominan t lesions. Lower motoneurone-type atrophy was not observed in this acute ph ase. We called 'poikilotonia' the striking unpredictable variations in musc le tone, ranging from extreme hypertonia to hypotonia, found in all patient s. When maintaining postures, patients showed large oscillations (100%), la terodeviation or levitation of the arm (60%), especially in the case of lar ge or posterior lesions, or, occasionally (3%), motor persistence or even h emicatalepsy (3%). Limb kinetic and manipulatory apraxia, with inadequate o rganization and anticipation of motor sequences and synergies, motor arrest s, perplexity, unrecognizable gestures and loss of bimanual coordination, w as a constant finding (100%). Other apraxias (62%) and difficulty in copyin g intransitive gestures of the hand (84%) were associated with posterior le sions involving the supramarginal gyrus. When reaching towards objects, all patients showed abnormal anticipatory hand shaping, but visuomotor ataxia (3%) was only seen with bilateral posterior stroke. Sensory (70%) or pseudo cerebellar (4%) ataxia: was seen in both anterior and posterior lesions. Av oidance behaviors (34%) were not uncommon, but had no localizing value. Of the dyskinesias, hand dystonia (84%) was frequent, but athetosis (16%), ast erixis (15%): postural tremor (15%), myoclonus (9%) and stereotypia (9%), w ere uncommon. The abnormal eye movements were unilateral hypo-akinesia of e xploratory saccades (43%), abnormal ipsilateral pursuit and contralateral o ptokinetic nystagmus in the case of posterior lesions, and oculomotor aprax ia with bilateral posterior lesions. In conclusion, parietal motor syndrome can be recognized during bedside examination, and probably reflects the lo ss of multiple sensory feedback to motor programs, especially those directe d to the extrapersonal space. (C) 1998 Elsevier Science B.V. All rights res erved.