The efficacy of a trunk strengthening program for improving postural stability in people with Parkinson’s Disease: A randomised controlled trial

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by a series of motor and non-motor symptoms that collectively impact the independence and quality of life of this population. Symptoms of postural instability are amongst the most disabling and appear to be significantly influenced by a reduced capacity to control the trunk segment due to impaired trunk muscle function, muscle weakness and reduced inter-segmental mobility. Considering the trunk comprises approximately 60% of the body’s weight and that standard pharmacological therapies are known to be largely ineffective for the management of symptoms affecting this segment (i.e. axial symptoms), it is clear that alternative therapies are required to ensure postural stability during dynamic tasks. Exercise has been shown to be successful for improving various measures of clinical balance and motor function in people with PD, but the evidence for its capacity to improve dynamic postural stability and reduce falls in this population is less conclusive. The inconsistent findings presented in previous studies may be explained, at least in part, by the tendency for such research to rely upon clinical tests of mobility and balance that incorporate Likert scales that lack the capacity to detect subtle changes in function. With recent advances in the usability of wearable sensor technologies, it is now possible to incorporate these highly sensitive devices to improve the objectivity of postural stability assessments. Despite the potential of these systems, there is a need for clearer guidelines regarding the best placements and outcome measures to use to help guide their use in clinical settings. To address the apparent shortcomings of the existing literature, the four studies presented in this dissertation sought to determine whether wearable sensors could be used to improve clinical assessments of postural stability in people with PD and to examine whether a 12-week trunk-specific exercise intervention was capable of improving measures of static and dynamic postural stability in this population.