Het Vibrotactiel Labyrinthair Substitutie systeem (VLS)

We developed an ambulant Vibrotactile Labyrinthine substitution System (VLS) to improve posture and balance control in patients with bilateral vestibular dysfunction by use of tactile feed back. The VLS provides coded information about body tilt and motion, measured by accelerometers, and uses vibrotactile feedback to the trunk. The VLS was tested in 40 adult patients with severe bilateral vestibular hyporeflexia. The impact of the VLS on stance was evaluated by stabilometry and impact on gait by video recordings. A comparison was made between the VLS correctly activated versus inactivated versus placebo activated. Quality of balance in stance was based upon body sway angle. Three experts, blinded for the activation state of the VLS, ranked gait from best to worse from videorecordings. Body sway was significantly improved in 21 patients (almost 90% of our most severely handicapped patients) using vibrotactile feedback. In about half of them this improvement is at least partially due to a placebo or cognitive effect. The VLS improved postural stability in stance and during walking in 60% of our patients and about 80% felt more confident regarding their postural stability.