Trunk muscle performance in early Parkinson's disease

Background and Purpose. Altered trunk function has been observed in people 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 assessed using an Isostation B-200. Results. Group effects between the subjects with PD and the subjects without PD were found for all variables. 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. Conclusion and Discussion. People with PD exhibit less axial range of motion and isometric and isoinertial ability compared with persons without PD. There is a loss of the ability to extend the trunk early in the disease. These findings suggest the importance of further investigation into the role of strengthening programs soon after a diagnosis of PD in order to potentially delay changes in trunk function and subsequent functional difficulties.