Background and Purpose. Altered trunk function has been observed in pe
ople with Parkinson's disease (PD). Subjects. This study investigated
the trunk function of people with PD, as compared with people without
PD. Methods; Range of motion (against 1 N.m of resistance), isometric
torque, and isoinertial performance against moderate resistance were a
ssessed using an Isostation B-200. Results. Group effects between the
subjects with PD and the subjects without PD were found for all variab
les. Range of motion into extension and maximum and average isometric
torque in the directions of extension and right rotation showed group
effects between subjects classified as being in Hoehn and Yahr stage I
and subjects classified as being in Hoehn and Yahr stage II. Conclusi
on and Discussion. People with PD exhibit less axial range of motion a
nd isometric and isoinertial ability compared with persons without PD.
There is a loss of the ability to extend the trunk early in the disea
se. These findings suggest the importance of further investigation int
o the role of strengthening programs soon after a diagnosis of PD in o
rder to potentially delay changes in trunk function and subsequent fun
ctional difficulties.