Spinal movement and performance of a standing reach task in participants with and without Parkinson disease

Background and Purpose. Evidence Suggests that individuals with early and m id-stage Parkinson disease (PD) have diminished range of motion (ROM). Spin al ROM influences the ability to function. In this investigation, the autho rs examined available spinal ROM, segmental excursions (the ROM used) durin g reaching, and their relationships in community-dwelling adults with and w ithout PD. Subjects. The subjects were 16 volunteers with PD (modified Hoeh n and Yahr stages 1.5-3) and 32 participants without PD who were matched fo r age, body mass index, and sex. Methods. Range of motion of the extremitie s was measured using a goniometer, and ROM of the spine was measured using the functional axial rotation (FAR) test, a measure of unrestricted cervico -thoracic-lumbar rotation in the seated position. Motion during reaching wa s determined using 3-dimensional motion analysis. Group differences were de termined using multivariable analysis of variance followed by analysis of v ariance. Contributions to total reaching distance of segmental excursions ( eg, thoracic rotation, thoracic lateral flexion) were determined using forw ard stepwise regression. Results. Subjects with PD as compared with subject s without PD had less ROM (FAR of 98.2 degrees versus 110.3 degrees, should er flexion of 151.9 degrees versus 160.1 degrees) and less forward reaching (29.5 cm versus 34.0 cm). Lateral trunk flexion and total rotation relativ e to the ground contributed to reaching, with the regression model explaini ng 36% of the variance. Discussion and Conclusion. These results contribute to the growing body of evidence demonstrating that spinal ROM is impaired early in PD.