Balance Rehabilitation With Modified Visual Input in Patients With Neuropathy

Balance REhabilitation With Modified Visual Input in Patients With acQuired Chronic Demyelinating Neuropathy and PROprioceptive Disorders

This research focuses on the effects of rehabilitation on balance, in patients with acquired chronic demyelinating neuropathy. Rehabilitation will be performed with or without vision.

It is planned to include 40 subjects consulting for walking instability related to sensitivity disorders.

This multicenter study will take place in Paris's area. Each participant will benefit from 20 rehabilitation sessions with a Physical Therapist and 3 assessments.

Thanks to randomization, patient will be allocated in one of the 2 following groups:

• Control group, Patients will benefit from balance rehabilitation with open eyes.
• Experimental group, they will perform the same exercises while keeping their eyes closed or their vision will be obstructed by a mask or disturbed by moving luminous dots projected on the environment in darkness.

Patients with chronic acquired demyelinating neuropathy may be referred for instability or falls when walking. Some of them have complaints of dysesthesia, paresthesia. The majority of these patients, due to the involvement of large sensory fibres, have deep and superficial sensitivity disorders (hypoesthesia or anaesthesia), which explain proprioceptive ataxia and balance disorders.

In a given situation, an individual maintains his or her balance thanks to sensory information, among which he or she may have to choose the most appropriate one for the context. A good balance control depends on the ability to select the best information, but many subjects do not have, or have lost, this ability, giving too systematically priority to the same sensory input. This is what is called sensory preferences or sensory profiles that differ from one subject to another. The most common behaviour is visual dependence.

This tendency to visual dependence has been described in different pathological situations, especially after a stroke. Research has shown that specific rehabilitation in visual deprivation can reduce visual dependence and improve balance and walking autonomy in stroke patients.

The investigators have shown in previous work that patients with acquired chronic demyelinating neuropathy have ataxic symptomatology with a visual dependence behavior, while a good sensitivity to vibration stimulation of proprioceptive pathways persists. The proprioceptive potential still present seems to be under-used.

Rehabilitation of patients with peripheral neuropathy involves many techniques, such as muscle strengthening, vibration, virtual reality, Tai chi, electrical stimulation, etc. However, some techniques, such as the use of virtual reality or visual biofeedback, tend to increase the use of the visual input, which could be detrimental to other inputs. The specific approach to balance disorders in these patients through manipulation of the visual input has, to our knowledge, not been studied. This is the objective of the study.

The main hypothesis of this research is that rehabilitation with modified visual input can, by reducing visual dependence, strengthen the proprioceptive input that still appears to be available in these patients with acquired chronic demyelinating neuropathy, despite deficits already present, and thus improve balance and walking ability.

Inclusion Criteria:

• Patients with chronic demyelinating acquired neuropathy
• Age ≥ 18 years.
• Patients able to walk 20 meters without human assistance at least indoors with or without technical assistance.
• Patients with complaints such as discomfort, walking instability related to sensitivity disorders.
• Patients being clinically stable for at least 2 months, regardless of ongoing treatments.
• Patients who have provided consent.

Exclusion Criteria:

• Patients unable to walk 20 metres without technical and human assistance indoors.
• Patients with an ongoing hospitalization.
• Patients already included and participating in another intervention study.
• Patients with ongoing balance rehabilitation and continued during the REQ-PRO program in another rehabilitation centre or practice.
• Patients with ongoing acute treatment (related to polyneuropathy) started less than 2 months ago or stopped less than 2 months ago.
• Patients with scheduled surgery during the period of the patient's participation in the protocol, preventing the successful completion of the rehabilitation program and participation in assessments.
• Patients with recent surgery, in particular lower limb prosthesis (less than 1 year old) or equipment contraindicated for planned exercises such as standing kneeling positions.
• Patients with skin wounds on the foot that contraindicate rehabilitation.
• Patients with balance disorders of vestibular origin or central neurological pathology.
• Patients with a visual disability.
• Patients with a hearing impairment that prevents the patient from hearing and understanding instructions during the rehabilitation program or assessments.
• Patients with an inability to speak or understand the French language.
• Patients with cognitive or language impairments that prevent understanding of the protocol.
• Patients with a residence outside of the Paris Region (Ile de France).
• Patients with a known pregnancy.
• Patients not affiliated to a social security system (beneficiary or having a right), deprived of their right, under guardianship, curatorship, prisoner.