People with an unstable gait are at risk of falling. Unstable gait occurs among many groups of people, for example, the elderly, people with cerebral palsy, bilateral vestibular loss (BVL), dementia or Parkinson's disease, people who have suffered a stroke, an amputation, a bone fracture or a hip replacement, in particular during the period of rehabilitation after the stroke or hip replacement or women who are pregnant.
There are a number of devices available for people to wear that can alert the user that they may be at a temporarily increased risk of falling, for example if they are unbalanced. Particular devices provide a belt that is worn around the user's waist and that vibrates in response to a measurement of the inclination of the user's posture that indicates that the user is unbalanced or at an increased risk of falling. On sensing the vibration, the user is made aware that they are at an increased risk of falling. The type of tactile feedback used in these devices is sometimes referred to as “vibrotactile”.
In fall prevention, it is less of a concern to control balance, but rather to warn the user when their balance is temporarily reduced, for example because the person is paying attention to something in addition to walking, or the environmental conditions are suboptimal (for example there is dimmed lighting, an irregular ground surface, an overload of the auditory and visual systems due to too many stimuli, such as conversations, etc.).
In these cases, as the user is distracted, providing continuous feedback to the user on their posture is less effective at preventing falls.
There is therefore a need for an improved fall prevention system and method that overcomes the disadvantages with the known devices.