Article

The purpose of this study is to delineate the impairments of body
functions and structures which specifically inhibit mechanomyography (MMG)-based
switch control as an alternative access pathway. METHOD: Seven individuals with
severe physical disabilities and varied diagnoses of neuromuscular or
neurological conditions tested a MMG switch. A semi-structured protocol was used
to gather quantitative and qualitative indications of the switch's performance,
and descriptive perceptions of the participants and their care givers. RESULTS:
The participants controlled the switch by contracting muscles of their forehead,
forearm or shoulder. Body functions and structures that negatively affect the
signal-to-noise ratio (SNR) of the recorded MMG signal included involuntary
dystonic movement, impaired muscle control, atrophied muscles, muscle spasticity
and involuntary activity of neighbouring muscles. CONCLUSIONS: The MMG switch is
strongly recommended where the muscle site and its control are intact and signal
artefact is minimal. Its viability when muscle activity at the access site may be
confounded by signal artefact is dependent on the strength of the voluntary
muscle contraction relative to that of artefacts such as spastic contractions,
involuntary dystonic movements, muscle spasms and physiological vibrations.
Neurological conditions, such as spasticity, that compromise the user's ability
to voluntarily contract or suppress muscle contractions may be considered
contraindications to MMG-based access.
CI - (c) 2011 Informa UK, Ltd.

Langue : ANGLAIS