Are clinical characteristics associated with upper-extremity hypertonia in severe ischaemic supratentorial stroke?

OBJECTIVE: The primary goal of this study was to identify clinical risk factors, in addition to muscle weakness, for upper-extremity hypertonia in patients with severe ischaemic supratentorial stroke. The secondary goal was to investigate the time course of upper-extremity hypertonia in these patients during the first 26 weeks post-stroke. DESIGN: Inception cohort. PATIENTS: Forty-three consecutive patients with an acute ischaemic supratentorial stroke and an initial upper-extremity paralysis admitted to an academic hospital. PRIMARY OUTCOME: hypertonia assessed by the Ashworth scale at week 26 post-stroke. Potential risks factors: motor functions assessed by the upper-extremity subscore of the Fugl-Meyer motor assessment, Barthel Index at week 1, consciousness, sensory disturbances, apraxia, neglect, and hyper-reflexia. Secondary outcome: time course of upper-extremity hypertonia by assessing its prevalence at 6 consecutive moments post-stroke during a follow-up period of 26 weeks. RESULTS: Twenty-five patients (63%) developed hypertonia during the follow-up period of 26 weeks. During this period, the prevalence of hypertonia followed a rather dynamic course, with cases of early, transient and late hypertonia. Univariate analyses yielded none of the selected clinical characteristics as significantly associated with hypertonia. CONCLUSION: Despite the high incidence of hypertonia (63%) observed, none of the selected clinical characteristics could be identified as a risk factor for hypertonia.