Multiple Sclerosis is a very disabling disorder in young adult patients leading to an important limitation in daily life activities and social participation. Among of the different causes of disability in MS patients gait impairments, fatigue and balance disorders can be considered as the main concerns. Thus, gait restoration in patients with MS is the one of the primary objective of rehabilitation and often influences whether a patient can return home or to work. Even if potentially innovative treatments like treadmill training have been proposed, nowadays the role of robotic assisted locomotion rehabilitation has not been extensively studied in patients with MS.

Background Multiple sclerosis (MS) is the most common chronic disabling disease of the central nervous system in young adults. Gait disorders represent one of the greatest causes of disability in patients with MS. Thus, gait restoration in patients with MS is the one of the primary objective of rehabilitation and often influences whether a patient can return home or to work.

Despite significant progress in the development of disease-modifying drugs, pharmacologic therapy alone does not warrant optimal care in MS. Exercise has been recognized as a feasible form of self-management for persons with the disease. Regular exercise can improve daily activity, cardiovascular fitness, muscle strength, health perception, and reduce fatigue in patients with MS.

To restore gait, modern concepts of rehabilitation support a repetitive task-specific approach. In recent years it has also been shown that higher intensities of walking practice (resulting in more repetitions trained) result in better outcomes for patients after stroke. Recently, the introduction of robotic devices for gait rehabilitation have showed to be a feasible approach in order to improve gait ability in patients with stroke and spinal cord lesions. These devices allow to train patients under a graduated body weight support condition and to guide the patient's steps reproducing a physiologic gait pattern for as long as the clinical conditions allow. This activity can be executed requiring only supervision by a physiotherapist and in absolutely safety condition for the patient.

Repetitive locomotor training is an innovative approach in gait disturbances in patients with multiple sclerosis. Only scant data on this issue is available and all these studies have been performed by means of conventional physiotherapy or treadmill training approaches. Nowadays the effectiveness of robotic devices for gait rehabilitation has not yet been evaluated in patients with multiple sclerosis.

Aim of the study The aim of the study is to evaluate the effect of a repetitive locomotor training by electromechanical gait trainer on gait endurance, fatigue and activities daily life in patients with MS.

Study Design Randomised controlled, blinded clinical trial. Materials and methods Fifty patients with definite diagnosis of MS according to McDonald criteria, and with EDSS score equal to or below 7 will be enrolled in the study. Patients with disease recurrence that worsens significantly during the 8 weeks before recruitment will be excluded. At the moment of recruitment (before treatment), at the end of treatment (6 weeks) and one month after the end of the treatment (FU) each patient will be tested with the following clinical and instrumental procedures. Clinical assessment procedures: 6-minute Walking Test, 10-meter Walking Test, Fatigue Severity Scale, Multiple Sclerosis Quality Of Life-54, Hamilton Rating Scale for Depression, Falls Efficacy Scale. Instrumental assessment procedures: GAITRite® System, Stabilometric Assessment and measure of energy cost by COSMED K4b2.

As primary outcome measure will be considered the 6-minute Walking Distance Test. As secondary outcomes measures will be considered the 10-meter Walking Test, Fatigue Severity Scale and the Multiple Sclerosis Quality Of Life-54, Hamilton Rating Scale for Depression, Falls Efficacy Scale, Spatio-temporal parameter with GAITRite® System, Stabilometric Assessment and measure of energy cost by COSMED K4b2. The allocation in the two groups will be done with simple randomisation.

Patients will be randomized into two groups. The first group (experimental group) will be subjected to 12 treatment session (2 sessions/week) on Gait Trainer machine. The second group (control group) will undergo to a conventional treatment with the same duration and frequency of the experimental group. Data will be analysed by means parametric and non-parametric tests. Both, within and between groups comparison will be performed. Data will be analyzed using SPSS software (ver 11.0; SPSS Inc., Chicago, IL, USA). Expected results: we could hypothesize that the training performed by the experimental group could improve gait endurance and daily life disability in patients with MS.

Inclusion Criteria:

1. age between 30 and 60 years
2. Expanded Disability Status Scale (EDSS) score 2.0≥ x ≤ 4.0
3. Mini Mental State Evaluation (MMSE) score ≥ 24
4. absence of heart problems
5. ability to maintain standing position without aids for at least 1 minute
6. ability to walk independently for at least 15 metres
7. absence of concurrent neurological or orthopaedic diseases that interfere with deambulation.

Exclusion Criteria:

1. disease recurrence that worsens significantly during the 3 months prior to recruitment
2. pharmacological therapy not well defined
3. performance of any type of rehabilitation treatment in the month prior to recruitment
4. presence of other concurrent neurological or orthopaedic diseases involving the lower limbs and/or interfering with standing position and/or walking