Balance disorders are frequently observed in patients with Multiple Sclerosis (MS) and the deterioration of the static and dynamic control of balance is an important and basic symptom of disease progression.

Measure balance disorders with force platforme requires personnel and represent a significant cost.

The platform Nintendo Wii Fit represents a valid economic alternative

Balance disorders are frequently observed in patients with MS and are the most disabling symptoms; in subjects with moderate disabilities for balance, the deterioration of the static and dynamic control of balance is an important and basic symptom of disease progression.

From a clinical point of view, the reliability of being able to discriminate patients who have the highest probability of falling than those with lower probability is crucial to develop a program aimed at the prevention of falls.

Potentially the parameters measured wiht torque platform can be an objective, reliable and accurate for discriminating patients with the highest probability of falling than those with low probability, and may be useful to highlight the deficits and improvements in the ability to maintain balance after specific rehabilitation. However posturographic systems represent a significant cost, require a dedicated and qualified personnel to use. A possible solution to not use force platforms could be the implementation of software to interface with the Nintendo Wii Fit Balance Board (WBB) with a personal computer.

The platform Nintendo Wii Fit presents a set of sensors lower compared to a traditional force platform, but can represent a valid economic alternative to more complex systems, in addition to being already used as a rehabilitation tool in the literature in more than one study. Studies in healthy subjects have valid information on the study of the center of pressure (COP) obtained from WBB showing that the path lengths of the COP obtained from the WBB were valid and well correlated with those recorded by a dynamometric platform.

Inclusion Criteria (Healthy subjects):

• Male and female, aged > 18, < 80 years;
• healthy.

Exclusion Criteria (Healthy subjects):

• pregnancy;
• previous diagnosis of debilitating diseases;
• previous diagnosis of orthopedic, neurological, vestibular or that may affect the balance.

Inclusion Criteria (Multiple Sclerosis subjects):

• Male and female, aged > 18, < 80 years;
• subjects with a diagnosis of MS according to the McDonald criteria in course with relapse and remission, progressive, primary or secondary are included in the study;
• absence of disease exacerbations in the 3 months prior to enrollment;
• mild or moderate gait disability identified with the Expanded Disability Status Scale (EDSS) score not higher than 5.5. This degree of severity refers to a subject with restriction ambulatory activity but which does not require constantly an unilateral support (stick, crutch, other) for walking.

Exclusion Criteria (Multiple Sclerosis subjects):

• cognitive impairment assessed with Mini Mental Status Examination (MMSE) <24;
• neurological diseases associated with MS with possible involvement of motor functions;
• of internal conditions that might interfere with the ability to complete the study protocol in a secure manner;
• severe cognitive-behavioral (score less than 24 on the Mini Mental Status Examination);
• pregnancy;

Will be recruited 20 healthy subjects and 20 subject with a diagnosis of multiple sclerosis and mild to moderate disability ambulatory identified with a value not higher than 5.5 EDSS score. The subjects of both groups will be age-matched to exclude differences caused by age posturographic. All individuals carry out the task of torque balance both on the platform and on the Wii Fit Balance Board on the same day.