  Due to the fact that no study to date has shown the experimental validity of
ACC-based measures of body sway with respect to posturography for subjects with
vestibular deficits, the aim of the present study was: i) to develop and
validate a practical tool that can allow clinicians to measure postural sway
derangements in an otoneurological setting by ACC, and ii) to provide reliable,
sensitive and accurate automatic analysis of sway that could help in
discriminating unilateral vestibular failure (UVF) patients. Thus, a group of
13 patients (seven females, 6 males; mean age 48.6 +/- 6.4 years) affected for
at least 6 months by UVF and 13 matched healthy subjects were instructed to
maintain an upright position during a static forceplate-based posturography
(FBP) acquisition while wearing a Movit sensor (by Captiks) with 3-D
accelerometers mounted on the posterior trunk near the body centre of mass.
Pearson product moment correlation demonstrated a high level of correspondence
of four time-domain and three frequency-domain measures extracted by ACC and
FBP testing; in addition, t-test demonstrated that two ACC-based time- and
frequency-domain parameters were reliable measures in discriminating UVF
subjects. These aspects, overall, should further highlight the attention of
clinicians and researchers to this kind of sway recording technique in the
field of otoneurological disorders by considering the possibility to enrich the
amount of quantitative and qualitative information useful for discrimination,
diagnosis and treatment of UVF. In conclusion, we believe the present ACC-based
measurement of sway offers a patient-friendly, reliable, inexpensive and
efficient alternative recording technique that is useful - together with
clinical balance and mobility tests - in various circumstances, as well as in
outcome studies involving diagnosis, follow-up and rehabilitation of UVF
patients.
