The instrumental evaluation of standing postural control by posturographic analysis supplements the clinical evaluation and, as such, is recommended by the French National Authority for Health (HAS 2007). The quantitative data obtained after a standardized postural examination appear relevant for the longitudinal follow-up of neuromuscular patients and hemiparetic patients. Neuro muscular (NM) diseases are progressive, these instrumental evaluations can highlight a deterioration or stabilization of postural control possibly not observable with the scores on clinical scales.

The K-Force Plates, recently developed appear to be an interesting alternative to the stabilometry platforms currently used. Static and dynamic conditions in upright position are tested. Moreover, posturologic, kinematics data and clinical scores are correlated to increase understanding of strategies during postural control tasks in patients with stroke and in patients with NM disorders.

To date, no clinical validation study of these K-Force Plates force platforms has been proposed. The investigator hypothesize that the data obtained by the Plates are comparable to the measurements made by the reference tool, the AMTI platforms during a static and dynamic posturographic examination in MNM, hemiparetic and healthy subjects. The strategies of the patients (stroke and NM) during the dynamic task are also explored with kinematic analysis in correlation with data from force platforms and clinical scores.

"Eligible couples must present all the following criteria :

• Signing of the informed consent form
• Men and women aged from 18
• Single stroke hemiparetic patient, or patient with neuro-muscular disease, or healthy subject free of neurological disorder and other disease
• Patient able to stand alone at least 30 seconds without technical assistance (multiple repetitions)

To be included, patient should not present any of the following criteria :

• Bilateral brain injury, cerebellar syndrome
• Other disease or defect that may interfere with the study such as visual, vestibular or other related uncontrolled medical condition
• Major cognitive impairment that does not allow evaluation
• Pregnant women, breastfeeding
• Non affiliated to a social security scheme"

Single stroke hemiparetic patient, or patient with neuro-muscular disease, or healthy subject free of neurological disorder and other disease.