The coefficient of friction in Parkinson�s disease gait

Abstract

SummaryThis study aimed to characterize the coefficient of friction (COF) curves of patients with Parkinson's disease (PD) during barefoot gait and to evaluate the relationships between this variable and functional scales. Twenty-two subjects with PD (ON phase of levodopa) and 22 healthy subjects participated in this study. The participants walked barefoot along a pathway that went over two force plates embedded in the floor of the data collection room. The instantaneous COF was calculated as the ratio between the horizontal and vertical components of the ground reaction forces. Two-sample t-tests applied to every 1% of the support phase of the COF curve were used to compare the groups and to identify the phases in which the two groups were different. Specifically, three COF areas were computed: Area 1 (for the loading response phase), Area 2 (for the midstance phase) and Area 3 (for the terminal stance phase). Pearson's tests were applied to assess the associations between the COF curve areas and the clinical scales. The subjects with PD exhibited lower COF values during the loading response and terminal stance phases and higher COF values during the mid-stance phase compared with the control group. A strong positive correlation was observed between Area 1 and the Timed Up and Go Test (90.3%). In conclusion, the patients' COFs exhibited patterns that were different from those of the control group. Moreover, during the loading response phase, these differences were well-correlated with the Timed Up and Go Test scale data; Timed Up and Go Test data can be used to identify the risk of falls among PD patients.

Slip avoidance strategies in children with bilateral spastic cerebral palsy and crouch gait

“…These are the moments when slips are more likely to occur (Chang et al, 2011;Redfern et al, 2001). Additionally, the valley is observed in the mid-stance phase (Kleiner et al, 2015b;Kleiner et al, 2017;Pacifici et al, 2016). The lower the value of the valley, the higher the lower limb joints range of motion (Kleiner et al, 2015b;Kleiner et al, 2017;Pacifici et al, 2016).…”

“…The RCOF has already been quantified in elderly (Anderson et al, 2014;Kleiner et al, 2015b) and in subjects with Parkinson's disease, stroke and multiple sclerosis (Kleiner et al, 2014;Kleiner et al, 2015a;Kleiner et al, 2017;Pacifici et al, 2016), where the strategies used by these populations to avoid a slip or a fall were described. Subjects with Parkinson's disease, thanks to their shuffling gait pattern, presented lower RCOF values in loading response and push-off phases and higher RCOF values during mid-stance phase when compared to healthy controls (Kleiner et al, 2017). The impaired ankle range of motion control in subjects with multiple sclerosis causes an increased RCOF in the push-off phase when compared to a reference group (Pacifici et al, 2016).…”

Haftung für Schäden durch KI in der Medizin

“…Diese wäre von denjenigen aufzubringen, die sonst persönlich für die vom Roboter verursachten Schäden haften müssten, also insbesondere Hersteller und Anwender. 126 Im wirtschaftlichen Ergebnis wird mit Anerkennung der e-Person die Haftung der sonst verantwortlichen Akteure auf die Versicherungssumme des Roboters reduziert. 127 Es stünde zu befürchten, dass die Nutzer autonome Systeme als Haftungsschild missbrau chen.…”