The effectiveness of deep brain stimulation in improving upper and lower extremity function under dual task conditions in Parkinson?’s disease patients

The effectiveness of deep brain stimulation in improving upper and lower extremity function under dual task conditions in Parkinson?’s disease patients

Frankenmolle, A.M.M.

Van der Helm, F.C.T. (mentor)
Schouten, A.C. (mentor)

Mechanical, Maritime and Materials Engineering

BioMechanical Engineering

BME

2012-12-14

Parkinson?’s disease (PD) is a progressive neurodegenerative disorder characterized by reduced movement. Postural instability and gait dysfunction (PIGD) is one of the more debilitating symptoms of PD due to its effect on activities of daily life and increased risk for falls. In later stages of the disease, cognitive impairment affects executive functioning and working memory. Although, most activities in daily living require both motor and cognitive functioning like cycling (motor) while holding a conversation (cognitive). Bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) has been shown to reduce motor deficits in advanced Parkinson?’s disease patients. However, the effectiveness of STN DBS on postural instability is less pronounced. It has been shown that bilateral STN DBS results in cognitive declines under dual-??task conditions using an upper extremity task and these declines compromise motor function. The aim of this study was to asses the effectiveness of STN DBS on cognitive-??motor performance during a lower extremity task. 15 advanced PD patients, of which seven presented PIGD symptoms, were tested under single-?? and dual-??task conditions. All patients were bilaterally implanted with STN DBS and had stable parameters as determined through typical clinical programming for at least 6 moths prior to study enrollment. Patients were assessed off anti-??parkinsonian medication under two DBS settings; Off DBS and On DBS. In each condition, patients performed a working memory task (n-??back) and a postural stability task (quiet standing). During the dual task, patients performed the working memory and postural stability tasks simultaneously. DBS was effective in improving Unified Parkinson?’s disease Rating Scale III scores relative to no stimulation. Cognitive functioning showed no difference between the two DBS conditions. Patients with PIGD symptoms were significantly less stable than patients with no PIGD symptoms for both On and Off DBS conditions. These data show that with the paradigm used in this study, PIGD symptoms continue to be refractory to DBS. Postural stability as assessed by quietly standing on a force platform may not have been challenging enough to evoke cognitive declines.

Parkinson's Disease
deep brain stimulation
postural stability
cognitive function

http://resolver.tudelft.nl/uuid:f1e72647-dd51-4bba-907f-541f2509c0d9

Student theses

master thesis

(c) 2012 Frankenmolle, A.M.M.