Balance control asymmetries and stepping responses in Parkinson*s disease patients

Parkinson*s disease (PD) is an asymmetric disease; symptoms usually start on
one side of the body and this side remains the most impaired. Clinically,
asymmetry of symptoms is most evident for appendicular impairments (e.g., upper
and lower limb rigidity, bradykinesia and tremor). For axial impairments (i.e.,
stooped posture, shuffling gait, postural imbalance and freezing), asymmetry is
less obvious. To date, asymmetries in balance control in PD patients have
seldom been studied, but preliminary evidence suggests that balance control is
asymmetrically affected at least in some PD patients (Rocchi et al., 2002; van
der Kooij et al., 2007)). We would like to investigate asymmetries in balance
control in a larger group of patients and subsequently determine the clinical
relevance of this symptom (i.e., relationship with actual falls).

To investigate whether balance control is asymmetrical in PD patients. In
addition, we want to investigate the relationship between asymmetrical balance
control and stepping responses, fall history and freezing of gait.

Intervention, cross-sectional, non-invasive.
Methods: Biomechanical responses will be recorded using motion capture (VICON)
and a dual forceplate (AMTI) during quiet stance, small mechanical
perturbations and large platform translations. Patients will be tested during
their subjective on phase, using their regular medication regimen. Clinical
tests will be performed to determine disease severity and severity of axial
symptoms. In addition, participants will be asked to fill in questionnaires
regarding their balance during daily life.

Delay of moning dose of antiparkinsonian medication. Subsequently, the balance
of the patients will be challenged by applying external mechanical
perturbations.

Participants are asked to come to the VR-laboratory at the University of Twente
once. During a three hour experiment (including preparations and clinical
assessment), biomechanical responses will be measured. The burden and the risk
for the participants are very low. During the experiment participants will be
secured by a safety harness preventing falls. Benefit for participants: none.
Benefit for patients with Parkinson*s disease in general: novel insight into
PIGD pathology, potentially improving treatments such as physiotherapy and Deep
Brain Stimulation (DBS).