La Trobe University

About: La Trobe University is a education organization based out in Melbourne, Victoria, Australia. It is known for research contribution in the topics: Population & Health care. The organization has 13370 authors who have published 41291 publications receiving 1138269 citations. The organization is also known as: LaTrobe University & LTU.

Performance on Clinical Tests of Balance in Parkinson's Disease

Abstract: Background and Purpose. Due to the high incidence of falls in people with idiopathic Parkinson's disease (PD), the assessment of standing balance is a key component of physical therapist evaluation. This study investigated performance on clinical tests of standing balance in subjects with and without PD. Subjects. The subjects were 10 persons with PD who had a history of falls (age range=60–80 years), 10 persons with PD who had no history of falls (age range=63–79 years), and 10 persons with no known neurological impairment (age range=60–78 years) who served as a comparison group. Methods. Subjects were tested on their ability to maintain stability in 3 conditions: (1) steady standing (feet apart, feet together, tandem stance, step stance, and single-limb stance), (2) in response to perturbations generated by self-initiated movements (arm raise, functional reach, bend-reach, and step tests), and (3) in response to an external perturbation to upright stance (shoulder tug). Balance was measured at peak dosage in the levodopa medication cycle (in the morning) and 7 days later. Results. The mean Hoehn and Yahr Disability Scale score was 3.0 for the fallers with PD and 2.5 for the nonfallers with PD. Performance on the tandem stance, single-limb stance, functional reach, and shoulder tug tests demonstrated differences between the subjects with PD and the comparison group and between the fallers and nonfallers with PD. The results of these tests were highly repeatable over 7 days (ICC=.61–.94). Conclusion and Discussion. Although there was a small sample size, performance was highly consistent across 7 days when testing occurred during peak dosage of levodopa. A small battery of tests were sensitive enough to discriminate between people with PD who fall and those with no history of falls.

Abnormalities in the stride length-cadence relation in parkinsonian gait.

Abstract: The purpose of this investigation was to clarify abnormalities in the stride length-cadence relation in gait hypokinesia in Parkinson's disease (PD). A second aim was to investigate the effect of levodopa medication on the foot-step pattern. In the first experiment, 20 subjects with idiopathic PD and 20 age-, sex-, and height-matched controls performed a series of 10 m walking trials at cadence rates ranging from 40 steps/min to 180 steps/min. Cadence rates were set by an electronic metronome, and gait patterns were measured by using a footswitch stride-analyzer system. By instructing subjects to concentrate on walking in time to the metronome beat, the baseline stride length could be monitored for a range of velocities with the compensatory effects of cadence removed. Linear-regression analysis revealed that the mean slope for the regression of stride length against cadence was not different from normal in PD, although there was a statistically significant difference in mean intercept between the PD group (0.25) and the control group (0.59); [t (19) = -4.76; p = 0.0001]. The second experiment evaluated the effects of levodopa on stride-length regulation in 10 subjects with idiopathic PD on average 45 min before and after the first morning dose was administered. There was a statistically significant increase in stride length for all cadence rates from premedication to postmedication phases and the maximal stride length was achieved at higher cadence rates after medication. The slope of the regression of stride length against cadence did not alter according to medication status, although the mean intercept was significantly lower before levodopa (-0.06) compared with after levodopa (0.27); [t (9) = -3.83; p = 0.004]. These results suggest that defective scaling of stride length underlies gait disturbance in PD.