A paediatric physiotherapist had been working, unsuccessfully, to improve the walking posture of a child with a rare condition. The child had become a toe walker and, despite focussed physiotherapy and targeted botox treatments, the toe walking remained. Her previous experience of working with autistic children hinted that perhaps a sensory element is connected with the child’s condition. She discovered that, if she activated the vibration mode on her phone and placed this against the sole of the child’s foot, they enjoyed the sensation to such an extent that if the phone was moved, the child would follow with their foot. With impending surgery to lengthen tendons, it was imperative to find an effective physiotherapeutic solution to offer the best possible outcome.
An initial prototype allowed the angle range to be measured and the best vibration amplitude and frequency that would cause the child to seek the stimulation. The sweet spot was to get sufficient stimulation but without undue parasitic audio that would distract in a classroom situation. A number of vibration transducers were trialled, from the haptic feedback units in mobile phones through to those used in massage chairs, covering a range of voltages and powers. The optimum transducer was a nominal 12V used in the vibration cushion component of a massage chair. The power requirements are met with readily available mobile phone powerpacks that can easily be recharged with common mobile phone chargers and avoid trailing cables that a tethered power solution would entail. The foot holders are adjustable from +45 to –10 degrees in discreet steps and their length for differing foot and shoe sizes. Individual heel activation switches to ensure that the stimulation is only provided when each heel is in contact with its vibration plate.
A switched USB output is provided for control of external feedback devices (fun lights, movie players, etc) that can be configured to be on when either or both of the heel switches are depressed.
The device provides the incentives for the patient to maintain the therapeutic stretches as part of the physio regime pre and post surgery to maximise the potential outcomes from such an intervention.