References of "Demonceau, Marie"
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See detailExtraction of temporal gait parameters using a reduced number of wearable accelerometers
Boutaayamou, Mohamed ULg; Denoël, Vincent ULg; Bruls, Olivier ULg et al

in Proceedings of the 9th International Conference on Bio-inspired Systems and Signal Processing (2016)

Wearable inertial systems often require many sensing units in order to reach an accurate extraction of temporal gait parameters. Reconciling easy and fast handling in daily clinical use and accurate ... [more ▼]

Wearable inertial systems often require many sensing units in order to reach an accurate extraction of temporal gait parameters. Reconciling easy and fast handling in daily clinical use and accurate extraction of a substantial number of relevant gait parameters is a challenge. This paper describes the implementation of a new accelerometer-based method that accurately and precisely detects gait events/parameters from acceleration signals measured from only two accelerometers attached on the heels of the subject’s usual shoes. The first step of the proposed method uses a gait segmentation based on the continuous wavelet transform (CWT) that provides only a rough estimation of motionless periods defining relevant local acceleration signals. The second step uses the CWT and a novel piecewise-linear fitting technique to accurately extract, from these local acceleration signals, gait events, each labelled as heel strike (HS), toe strike (TS), heel-off (HO), toe-off (TO), or heel clearance (HC). A stride-by-stride validation of these extracted gait events was carried out by comparing the results with reference data provided by a kinematic 3D analysis system (used as gold standard) and a video camera. The temporal accuracy ± precision of the gait events were for HS: 7.2 ms ± 22.1 ms, TS: 0.7 ms ± 19.0 ms, HO: ‒3.4 ms ± 27.4 ms, TO: 2.2 ms ± 15.7 ms, and HC: 3.2 ms ± 17.9 ms. In addition, the occurrence times of right/left stance, swing, and stride phases were estimated with a mean error of ‒6 ms ± 15 ms, ‒5 ms ± 17 ms, and ‒6 ms ± 17 ms, respectively. The accuracy and precision achieved by the extraction algorithm for healthy subjects, the simplification of the hardware (through the reduction of the number of accelerometer units required), and the validation results obtained, convince us that the proposed accelerometer-based system could be extended for assessing pathological gait (e.g., for patients with Parkinson’s disease). [less ▲]

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See detailGait quantification through accelerometers and clinical tests: application to pathological gait
DEMONCEAU, Marie ULg; Boutaayamou, Mohamed ULg; Maquet, Didier ULg et al

Conference (2015, January 30)

Gait gives essential information to physiotherapists in the screening and follow-up of their patients suffering from orthopaedic, geriatric or neurologic diseases. Most of time, clinical practitioners ... [more ▼]

Gait gives essential information to physiotherapists in the screening and follow-up of their patients suffering from orthopaedic, geriatric or neurologic diseases. Most of time, clinical practitioners rely on visual observation of their patients during specific clinical tests that can highlight gait abnormalities (e,g., the Tinetti assessment tool, the timed up and go test, the 6 minutes walking test), but these tests provide little quantified information about gait. These rough methods are also limited by inter-rater subjectivity and lack of acuteness in the detection of subtle impairments. On the other hand, instrumented gait analyses offer a sharper investigation with the ability to record and quantify gait events that cannot be caught at simple visual observation. Unfortunately, cutting edge technologies often pay the price of a limited number of strides extracted, the need of a strictly controlled laboratory environment, development and maintenance by a specialized staff. For these reasons, instrumented gait analysis may stand beyond the financial and technical reach of many rehabilitative centres and private practitioners. Accelerometer technologies have considerably developed with the progress of wireless technologies. These lightweight and low-cost sensors allow quantified gait analyses that are not restricted to a laboratory environment but can also be used in medical offices and in combination with common clinical gait tests. This presentation relates the experiences of our departments with accelerometer systems and clinical testing in gait analysis of patients suffering from Parkinson’s disease. The aim of this intervention is to cross ideas and knowledge of clinical practitioners and engineers in the development a new gait analysis tool that could integrate routine evaluation of patients suffering from Parkinson’s disease and other conditions characterized by gait impairments. [less ▲]

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See detailContribution of a Trunk Accelerometer System to the Characterization of Gait in Patients With Mild-to-Moderate Parkinson’s Disease
Demonceau, Marie ULg; Donneau, Anne-Françoise ULg; CROISIER, Jean-Louis ULg et al

in IEEE Journal of Biomedical and Health Informatics (2015)

OBJECTIVE: Gait disturbances like shuffling and short steps are obvious at visual observation in patients with advanced Parkinson's disease (PD). However, quantitative methods are increasingly used to ... [more ▼]

OBJECTIVE: Gait disturbances like shuffling and short steps are obvious at visual observation in patients with advanced Parkinson's disease (PD). However, quantitative methods are increasingly used to evaluate the wide range of gait abnormalities that may occur over the disease course. The goal of this study was to test the ability of a trunk accelerometer system to quantify the effects of PD on several gait features when walking at self-selected speed. METHODS: We recruited 96 subjects split into three age-matched groups: 32 healthy controls (HC), 32 PD patients at Hoehn and Yahr stage < II (PD-1), and 32 patients at Hoehn & Yahr stage II-III (PD-2). The following outcomes were extracted from the signals of the tri-axial accelerometer worn on the lower back: stride length, cadence, regularity index, symmetry index and mechanical powers yielded in the cranial-caudal, antero-posterior and medial-lateral directions. Walking speed was measured using a stopwatch. RESULTS: beside other gait features, the PD-1 and the PD-2 groups showed significantly reduced stride length normalized to height (p<0.02) and symmetry index (p<0.009) in comparison to the HC. Regularity index was the only feature significantly decreased in the PD-2 group as compared with the two other groups (p<0.01). The clinical relevance of this finding was supported by significant correlations with mobility and gait scales (r is around -0.3; p<0.05). CONCLUSION: Gait quantified by a trunk accelerometer may provide clinically useful information for the screening and follow-up of PD patients. [less ▲]

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See detailSegmentation of gait cycles using foot-mounted 3D accelerometers
Boutaayamou, Mohamed ULg; Bruls, Olivier ULg; Denoël, Vincent ULg et al

in Proceedings of the IEEE International Conference on 3D Imaging 2015 (2015)

We describe a new gait segmentation method based on the continuous wavelet transform to identify stride-by-stride gait cycles from measurements of foot-mounted three-dimensional (3D) accelerometers. The ... [more ▼]

We describe a new gait segmentation method based on the continuous wavelet transform to identify stride-by-stride gait cycles from measurements of foot-mounted three-dimensional (3D) accelerometers. The detection of such gait cycles is indeed a crucial step for an accurate extraction of relevant gait events such as heel strike, toe strike, heel-off, and toe-off. We demonstrate the ability of this segmentation method, used in conjunction with a validated extraction algorithm, to calculate the following gait (duration) parameters for each gait cycle during the gait of a healthy young subject and of an elderly subject with Parkinson’s disease (PD) in OFF and ON states: durations of (1) loading response, (2) mid-stance, (3) push-off, (4) stance, (5) swing, (6) stride, (7) step, and (8) double support phases. The experimental results show that the proposed method can extract relevant refined gait parameters to quantify subtle gait disturbances in subjects with PD. [less ▲]

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See detailAmbulatory system using wearable accelerometers for gait analysis in Parkinson’s disease
Boutaayamou, Mohamed ULg; Demonceau, Marie ULg; Schwartz, Cédric ULg et al

in Proceedings of the 14th Belgian Day on Biomedical Engineering (2015)

We describe a signal-processing algorithm for gait analysis in Parkinson’s disease (PD) using an ambulatory system with wearable accelerometers. This algorithm is versatile enough to detect, on a stride ... [more ▼]

We describe a signal-processing algorithm for gait analysis in Parkinson’s disease (PD) using an ambulatory system with wearable accelerometers. This algorithm is versatile enough to detect, on a stride-by-stride basis, refined gait parameters that quantify subtle gait disturbances in PD in a rater-independent way. [less ▲]

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See detailAdded value of a triaxial accelerometer assessing gait parameters to predict falls and mortality among nursing home residents: A two-year prospective study.
Buckinx, Fanny ULg; Beaudart, Charlotte ULg; Slomian, Justine ULg et al

in Technology and health care : official journal of the European Society for Engineering and Medicine (2015), 23

BACKGROUND: Gait impairment seems to be a risk factor for falls and mortality. Because gait change cannot be determined easily with classical clinical tests, some authors have suggested that it might be ... [more ▼]

BACKGROUND: Gait impairment seems to be a risk factor for falls and mortality. Because gait change cannot be determined easily with classical clinical tests, some authors have suggested that it might be useful to use a gait-analysis system among elderly community-dwelling people. OBJECTIVE: The main objective of the present study was to determine the predictive value of a quantitative evaluation of the gait characteristics in nursing home residents for the occurrence of falls and death performed using a tri-axial accelerometer (Locometrix(R)). MATERIAL AND METHODS: One hundred elderly nursing home residents (80 women and 20 men, mean age 86.4 +/- 6.04 years) were included in this study with the aim to follow them for 2 years. Deaths and falls were systematically recorded. A quantitative evaluation of a 10-second walk was performed with a tri-axial accelerometer (Locometrix(R)). Demographic data (i.e age, sex, body mass index) and clinical data (i.e. fall risk evaluated by the Tinetti test) were also recorded. RESULTS: During the two years of follow-up, 27 patients died. After adjustment on all potential confounding variables, only body mass index was significantly associated with the risk of mortality with an odds ratio of 0.86 (95% CI: 0.77-0.96, p=0.04). At the end of the study period, 440 falls had occurred (mean: 4.44 +/- 6.79 falls per patient) but no single factors were independently associated with fall incidence. CONCLUSION: Our results show that a quantitative gait analysis performed using a tri-axial accelerometer is not predictive of long-term falls and mortality among nursing home residents. [less ▲]

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See detailValidation des paramètres de marche par un système accélérométrique (Locométrix*) à l'aide d'un système opto-électronique 3D (Coda Motion )
GILLAIN, Sophie ULg; Schwartz, Cédric ULg; Boutaayamou, Mohamed ULg et al

in Gériatrie et Psychologie Neuropsychiatrie du Vieillissement (2014), 12(supplément 3),

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See detailValidation des paramètres de marche par un système accélérométrique (Locométrix ®) à l’aide d’un système opto-électronique 3D (Coda Motion ®)
GILLAIN, Sophie ULg; Schwartz, C; Dramé, M et al

in Cahiers de l'Année Gérontologique (Les) (2014), 6(Suppl. 1), 186

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See detailEvaluation of the impact of 6-month training by whole body vibration on the risk of falls among nursing home residents, observed over a 12-month period: a single blind, randomized controlled trial.
Buckinx, Fanny ULg; Beaudart, Charlotte ULg; Maquet, Didier ULg et al

in Aging Clinical & Experimental Research (2014), 26(4), 369-376

BACKGROUND: We have previously shown that short sessions of whole body vibration (WBV) were not able to significantly improve fall risk among nursing home residents but some trends towards an improvement ... [more ▼]

BACKGROUND: We have previously shown that short sessions of whole body vibration (WBV) were not able to significantly improve fall risk among nursing home residents but some trends towards an improvement of motor capacity were observed. OBJECTIVE: The objective of the present study was to evaluate the impact of 6-month training by WBV on functional and motor abilities among nursing home residents observed over a 12-month period. METHODS: Patients were randomized into two groups: the WBV group which received three training sessions every week composed of five series of 15 s of vibration at 30 Hz intensity for a period of 6 months and a control group with normal daily life. The impact of this training on the risk of falls was assessed blindly after 6 and 12 months by the Tinetti Test, the "Timed Up and Go" test and a quantitative evaluation of a 10-s walk performed with a tri-axial accelerometer. The occurrence of falls was also observed. RESULTS: 62 elderly healthy volunteers, (47 women and 15 men, mean age 83.2 +/- 7.9 years) were included in this study. There was no significant difference between the two groups regarding the Tinetti test (p = 0.75), the "Timed Up and Go" test (p = 0.19) and the Locometrix(R) test, except for the step length, measured by dual task (p < 0.01). No significant inter-group difference in the frequency of falls was observed during the 12 months of research. A total of 42 falls were recorded during the first 6 months of experimentation: 24 falls in the treated group and 18 in the control group (p = 0.60). During the next 6 months, 19 falls occurred: 8 falls in the treated group and 11 in the control group (p = 0.52). CONCLUSION: This study failed to establish the effectiveness of low doses of WBV, under the conditions used in our study, on functional and motor abilities of institutionalized elderly patients. However, given the positive results of other studies, further investigations, with modified therapeutic protocols, seem necessary to clarify the effects of WBV in the elderly. [less ▲]

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See detailFacteurs de risque de chute chez des sujets résidant en maison de repos : étude prospective d'une durée de 2 ans
Buckinx, Fanny ULg; Beaudart, Charlotte ULg; Slomian, Justine ULg et al

in Gériatrie et Psychologie Neuropsychiatrie du Vieillissement (2014), 12(1), 164-165

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See detailFacteurs pronostiques de décès chez des sujets résidant en maison de repos suivis d'une manière prospective pendant une période de 2 ans
Buckinx, Fanny ULg; Beaudart, Charlotte ULg; Slomian, Justine ULg et al

in Gériatrie et Psychologie Neuropsychiatrie du Vieillissement (2014), 12(1), 73-74

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See detailEvolution sur deux ans des capacités fonctionnelles et motrices de sujets âgés résidant en maison de repos
Buckinx, Fanny ULg; Beaudart, Charlotte ULg; Slomian, Justine ULg et al

in Gériatrie et Psychologie Neuropsychiatrie du Vieillissement (2014), 12(1), 57-58

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See detailPrognostic factors of death among nursing homes residents followed prospectively for a period of 2 years
Buckinx, Fanny ULg; Slomian, Justine ULg; Maquet, Didier ULg et al

in Osteoporosis International (2014), 25(2), 121-122

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See detailEvolution over two years of functional and motor abilities among nursing home residents
Buckinx, Fanny ULg; Beaudart, Charlotte ULg; Slomian, Justine ULg et al

in Osteoporosis International (2014), 25(2), 121

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See detailRisk factors for falls among elderly nursing home residents: a 2-year prospective study
Buckinx, Fanny ULg; Beaudart, Charlotte ULg; Slomian, Justine ULg et al

in Osteoporosis International (2014), 25(2), 36-37

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