Compensatory postural adjustments in Parkinson’s disease assessed via a virtual reality environment

Abstract

Postural control is a complex dynamic mechanism, which integrates information from visual, vestibular and somatosensory systems. Idiopathic Parkinson's disease (IPD) patients are unable to produce appropriate reflexive responses to changing environmental conditions. Still, it is controversial what is due to voluntary or involuntary postural control, even less what is the effect of levodopa. We aimed to evaluate compensatory postural adjustments (CPA), with kinematic and time-frequency analyzes, and further understand the role of dopaminergic medication on these processes. 19 healthy subjects (Controls) and 15 idiopathic Parkinson's disease (IPD) patients in the OFF and ON medication states, wearing IMUs, were submitted to a virtual reality scenario with visual downward displacements on a staircase. We also hypothesized if CPA would involve mechanisms occurring in distinct time scales. We subsequently analyzed postural adjustments on two frequency bands: low components between 0.3 and 1.5 Hz (LB), and high components between 1.5 and 3.5 Hz (HB). Vertical acceleration demonstrated a greater power for discriminating IPD patients from healthy subjects. Visual perturbation significantly increased the power of the HB in all groups, being particularly more evident in the OFF state. Levodopa significantly increased their basal power taking place on the LB. However, controls and IPD patients in the ON state revealed a similar trend of the control mechanism. Results indicate an improvement in muscular stiffness provided by levodopa. They also suggest the role of different compensatory postural adjustment patterns, with LB being related to inertial properties of the oscillating mass and HB representing reactions to the ongoing visual input-changing scenario.

How Wearable Sensors Can Support Parkinson's Disease Diagnosis and Treatment: A Systematic Review

“…Different motor subtypes show differences in biological and pathophysiological aspects, so their identification can be useful in large clinical studies and to promote accurate personalized therapies. Yelshyna et al ( 2016 ) explored the mechanism underlying compensatory postural adjustments (CPA) by implementing a kinematic and time-frequency analysis based on IMU data during a virtual reality scenario to find differences between PwPD ON, PwPD OFF, and HC, to evaluate Ldopa effects. The lower band (LB) reflected the effect of Ldopa, while the higher band (HB) was responsible for the reaction to visual input-changing scenario; PwPD OFF showed abnormal CPA with respect to PwPD ON and HC in both bands.…”

“…The accelerometer-based approach makes it easier to quantify postural impairments compared to the conventional protocol with force plates, which are more expensive and not portable (Palmerini et al, 2011 ; Mancini et al, 2016 ; Ozinga et al, 2017 ). APA and postural sway, both in ML and AP directions, are the most analyzed features, able to differentiate between PD patients and HC (Ozinga et al, 2017 ) in the early stages of the disease (e.g., APA disruption can precede the compromission of the step execution) (Gago et al, 2015 ; Mancini et al, 2016 ), as well as between mild and severe PD groups (Baston et al, 2016 ) for differential diagnosis or between ON/OFF states for the advanced patients (Baston et al, 2016 ; Yelshyna et al, 2016 ). Alternatively, only one work took into account atypical parkinsonism (i.e., vascular PwPD) other than idiopathic PD patients (Gago et al, 2015 ), analyzing the response to L-dopa therapy.…”

Use of Immersive Virtual Reality in the Assessment and Treatment of Alzheimer’s Disease: A Systematic Review

“…This led to tasks not being assessed as independent screening measures [38] or the use of iVR simply making tasks more confusing for patient participants [35]. Gago et al used the same task to distinguish participants with AD [36] and Parkinson's disease [43] from controls. This measure was well tolerated by participants but may simply select out any patient at high risk of falls.…”

ESTUDO DE PRECISÃO DE UMA PLATAFORMA MULTI CÂMERAS RGBd PARA SISTEMAS DE REABILITAÇÃO

“…Em [10] é proposto a utilização de serious games e realidade virtual com Kinect para auxílio em atividades fisioterapêuticas. Uma das vantagens é proporcionada pelo efeito retroativo de cursores ou avatares que se movem em sincronia com os usuários, incentivando-os a realizar os movimentos de forma correta.…”

“…Uma das vantagens é proporcionada pelo efeito retroativo de cursores ou avatares que se movem em sincronia com os usuários, incentivando-os a realizar os movimentos de forma correta. Desta forma, o paciente se conscientiza sobre seu desempenho, aumentando sua motivação [10] [11]. Outra vantagem baseia-se na imersão do usuário em um contexto espaço-temporal, algo que é difícil conseguir a partir de terapias convencionais [12].…”