Comparison of balance assessment by sway magnetometry and force platforms.

Sway magnetometry, which monitors body movement at the hips, was compared with two commercial force platforms to determine its sensitivity in identifying differences in stability between eyes opened and eyes closed. Sway path length and area were examined. All devices showed an ability to distinguish between stability with eyes opened and eyes closed on repeated testing. The magnetometry system using path length analysis was most sensitive and was able to detect an increase in sway with eyes closed compared with eyes open for individual tests with 97% confidence (mean [+/- SD] path length Romberg Coefficient, .76 +/- .13). Standing on a rubber base caused destabilization of posture. Sway magnetometry is seen as a potentially useful tool in quantification of body sway to aid the clinician in assessment of balance in the dizzy patient.