1998 Volume 57 Issue 6 Pages 556-565
This study investigated the characteristics of postural sway in cases of Parkinson' s disease (PK). We examined 16 patients diagnosed with PK, of whom 2 were classified as positive symptoms (PK-P), while 6 (PK-Na) and 8 (PK-Nb) were found to exhibit negative symptoms. The subjects stood on a stabilometer with their eyes open or closed with both foot closed together, and the sway of the center of gravity of the body was recorded for one minute. This paper presents 20 measurements of stabilometry in PK, comparing the mean ±2 SD classified by gender and age of healthy subjects, mean ±1 SD, and with observation of factor analysis.
1) There were only a few cases demonstrating data exceeded the mean ±2 SD, considering each parameter. All cases of PK-Na and 6 of 8 PK-Nb cases exceeded the mean ±2 SD, considering every parameter.
2) Four of 8 PK-Nb cases exceeded the mean ± 1 SD, for area, locus length, Romberg's coefficient, vector of velocity in the forward-backward and right-left and standard deviation of amplitude probability density distribution in X- and Y- axes considering each parameter. The proportion of patients exceeding the mean was higher in PK-Nb than in PK-Na.
3) Factor 1 showed centripetal and forward-backward sway type with high factor loading as to locus length, high frequency band in X and Y, vector of velocity in the forward-backward and kurtosis of amplitude probability density distribution in Y. Factor 2 showed right-left and diffuse sway type with high factor loading as to area, vector of velocity in the right-left and standard deviation of amplitude probability density distribution in X and Y. Factor 3 showed displacement and multiple center type with high factor loading as to deviation of the center of sway in X and skewness of amplitude probability density distribution in X and Y.
