The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Shuichi Ikeda - One of the best experts on this subject based on the ideXlab platform.
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principal component analysis for Ataxic Gait using a triaxial accelerometer
Journal of Neuroengineering and Rehabilitation, 2017Co-Authors: Akira Matsushima, Kunihiro Yoshida, Hirokazu Genno, Shuichi IkedaAbstract:It is quite difficult to evaluate Ataxic Gait quantitatively in clinical practice. The aim of this study was to analyze the characteristics of Ataxic Gait using a triaxial accelerometer and to develop a novel biomarker of integrated gate parameters for Ataxic Gait. Sixty-one patients with spinocerebellar ataxia (SCA) or multiple system atrophy with predominant cerebellar ataxia (MSA-C) and 57 healthy control subjects were enrolled. The subjects were instructed to walk 10 m for a total of 12 times on a flat floor at their usual walking speed with a triaxial accelerometer attached to their back. Gait velocity, cadence, step length, step regularity, step symmetry, and degree of body sway were evaluated. Principal component analysis (PCA) was used to analyze the multivariate Gait parameters. The Scale for the Assessment and Rating of Ataxia (SARA) was evaluated on the same day of the 10-m walk trial. PCA divided the Gait parameters into four principal components in the controls and into two principal components in the patients. The four principal components in the controls were similar to those found in earlier studies. The second principal component in the patients had relevant factor loading values for Gait velocity, step length, regularity, and symmetry in addition to the degree of body sway in the medio-lateral direction. The second principal component score (PCS) in the patients was significantly correlated with disease duration and the SARA score of Gait (ρ = −0.363, p = 0.004; ρ = −0.574, p < 0.001, respectively). PCA revealed the main component of Ataxic Gait. The PCS of the main component was significantly different between the patients and controls, and it was well correlated with disease duration and the SARA score of Gait in the patients. We propose that this score provides a novel method to assess the severity of Ataxic Gait quantitatively using a triaxial accelerometer.
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Principal component analysis for Ataxic Gait using a triaxial accelerometer.
Journal of neuroengineering and rehabilitation, 2017Co-Authors: Akira Matsushima, Kunihiro Yoshida, Genno Hirokazu, Shuichi IkedaAbstract:It is quite difficult to evaluate Ataxic Gait quantitatively in clinical practice. The aim of this study was to analyze the characteristics of Ataxic Gait using a triaxial accelerometer and to develop a novel biomarker of integrated gate parameters for Ataxic Gait. Sixty-one patients with spinocerebellar ataxia (SCA) or multiple system atrophy with predominant cerebellar ataxia (MSA-C) and 57 healthy control subjects were enrolled. The subjects were instructed to walk 10 m for a total of 12 times on a flat floor at their usual walking speed with a triaxial accelerometer attached to their back. Gait velocity, cadence, step length, step regularity, step symmetry, and degree of body sway were evaluated. Principal component analysis (PCA) was used to analyze the multivariate Gait parameters. The Scale for the Assessment and Rating of Ataxia (SARA) was evaluated on the same day of the 10-m walk trial. PCA divided the Gait parameters into four principal components in the controls and into two principal components in the patients. The four principal components in the controls were similar to those found in earlier studies. The second principal component in the patients had relevant factor loading values for Gait velocity, step length, regularity, and symmetry in addition to the degree of body sway in the medio-lateral direction. The second principal component score (PCS) in the patients was significantly correlated with disease duration and the SARA score of Gait (ρ = −0.363, p = 0.004; ρ = −0.574, p
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Principal component analysis for Ataxic Gait using a triaxial accelerometer
BMC, 2017Co-Authors: Akira Matsushima, Kunihiro Yoshida, Hirokazu Genno, Shuichi IkedaAbstract:Abstract Background It is quite difficult to evaluate Ataxic Gait quantitatively in clinical practice. The aim of this study was to analyze the characteristics of Ataxic Gait using a triaxial accelerometer and to develop a novel biomarker of integrated gate parameters for Ataxic Gait. Methods Sixty-one patients with spinocerebellar ataxia (SCA) or multiple system atrophy with predominant cerebellar ataxia (MSA-C) and 57 healthy control subjects were enrolled. The subjects were instructed to walk 10 m for a total of 12 times on a flat floor at their usual walking speed with a triaxial accelerometer attached to their back. Gait velocity, cadence, step length, step regularity, step symmetry, and degree of body sway were evaluated. Principal component analysis (PCA) was used to analyze the multivariate Gait parameters. The Scale for the Assessment and Rating of Ataxia (SARA) was evaluated on the same day of the 10-m walk trial. Results PCA divided the Gait parameters into four principal components in the controls and into two principal components in the patients. The four principal components in the controls were similar to those found in earlier studies. The second principal component in the patients had relevant factor loading values for Gait velocity, step length, regularity, and symmetry in addition to the degree of body sway in the medio-lateral direction. The second principal component score (PCS) in the patients was significantly correlated with disease duration and the SARA score of Gait (ρ = −0.363, p = 0.004; ρ = −0.574, p
Horacio Kaufmann - One of the best experts on this subject based on the ideXlab platform.
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Relationship between proprioception at the knee joint and Gait ataxia in HSAN III.
Movement disorders : official journal of the Movement Disorder Society, 2013Co-Authors: Vaughan G Macefield, Lucy Norcliffe-kaufmann, Felicia B Axelrod, Horacio KaufmannAbstract:Hereditary sensory and autonomic neuropathy type III features a marked Ataxic Gait that progressively worsens over time. We assessed whether proprioceptive disturbances can explain the ataxia. Proprioception at the knee joint was assessed using passive joint angle matching in 18 patients and 14 age-matched controls; 5 patients with cerebellar ataxia were also studied. Ataxia was quantified using the Brief Ataxia Rating Score, which ranged from 7 to 26/30. Neuropathy patients performed poorly in judging joint position: mean absolute error was 8.7±1.0° and the range was very wide (2.8–18.1°); conversely, absolute error was only 2.7±0.3° (1.6–5.5°) in the controls and 3.0±0.2° (2.1–3.4°) in the cerebellar patients. This error was positively correlated to the degree of ataxia in the neuropathy patients but not the cerebellar patients, suggesting that poor proprioceptive acuity at the knee joint is a major contributor to the Ataxic Gait associated with hereditary sensory and autonomic neuropathy type III.
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Can loss of muscle spindle afferents explain the Ataxic Gait in Riley–Day syndrome?
Brain, 2011Co-Authors: Vaughan G Macefield, Lucy Norcliffe-kaufmann, Joel Gutiérrez, Felicia B Axelrod, Horacio KaufmannAbstract:The Riley-Day syndrome is the most common of the hereditary sensory and autonomic neuropathies (Type III). Among the well-recognized clinical features are reduced pain and temperature sensation, absent deep tendon reflexes and a progressively Ataxic Gait. To explain the latter we tested the hypothesis that muscle spindles, or their afferents, are absent in hereditary sensory and autonomic neuropathy III by attempting to record from muscle spindle afferents from a nerve supplying the leg in 10 patients. For comparison we also recorded muscle spindles from 15 healthy subjects and from two patients with hereditary sensory and autonomic neuropathy IV, who have profound sensory disturbances but no ataxia. Tungsten microelectrodes were inserted percutaneously into fascicles of the common peroneal nerve at the fibular head. Intraneural stimulation within muscle fascicles evoked twitches at normal stimulus currents (10-30 µA), and deep pain (which often referred) at high intensities (1 mA). Microneurographic recordings from muscle fascicles revealed a complete absence of spontaneously active muscle spindles in patients with hereditary sensory and autonomic neuropathy III; moreover, responses to passive muscle stretch could not be observed. Conversely, muscle spindles appeared normal in patients with hereditary sensory and autonomic neuropathy IV, with mean firing rates of spontaneously active endings being similar to those recorded from healthy controls. Intraneural stimulation within cutaneous fascicles evoked paraesthesiae in the fascicular innervation territory at normal stimulus intensities, but cutaneous pain was never reported during high-intensity stimulation in any of the patients. Microneurographic recordings from cutaneous fascicles revealed the presence of normal large-diameter cutaneous mechanoreceptors in hereditary sensory and autonomic neuropathy III. Our results suggest that the complete absence of functional muscle spindles in these patients explains their loss of deep tendon reflexes. Moreover, we suggest that their Ataxic Gait is sensory in origin, due to the loss of functional muscle spindles and hence a compromised sensorimotor control of locomotion.
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Can loss of muscle spindle afferents explain the Ataxic Gait in Riley-Day syndrome?
Brain : a journal of neurology, 2011Co-Authors: Vaughan G Macefield, Lucy Norcliffe-kaufmann, Joel Gutiérrez, Felicia B Axelrod, Horacio KaufmannAbstract:The Riley-Day syndrome is the most common of the hereditary sensory and autonomic neuropathies (Type III). Among the well-recognized clinical features are reduced pain and temperature sensation, absent deep tendon reflexes and a progressively Ataxic Gait. To explain the latter we tested the hypothesis that muscle spindles, or their afferents, are absent in hereditary sensory and autonomic neuropathy III by attempting to record from muscle spindle afferents from a nerve supplying the leg in 10 patients. For comparison we also recorded muscle spindles from 15 healthy subjects and from two patients with hereditary sensory and autonomic neuropathy IV, who have profound sensory disturbances but no ataxia. Tungsten microelectrodes were inserted percutaneously into fascicles of the common peroneal nerve at the fibular head. Intraneural stimulation within muscle fascicles evoked twitches at normal stimulus currents (10-30 µA), and deep pain (which often referred) at high intensities (1 mA). Microneurographic recordings from muscle fascicles revealed a complete absence of spontaneously active muscle spindles in patients with hereditary sensory and autonomic neuropathy III; moreover, responses to passive muscle stretch could not be observed. Conversely, muscle spindles appeared normal in patients with hereditary sensory and autonomic neuropathy IV, with mean firing rates of spontaneously active endings being similar to those recorded from healthy controls. Intraneural stimulation within cutaneous fascicles evoked paraesthesiae in the fascicular innervation territory at normal stimulus intensities, but cutaneous pain was never reported during high-intensity stimulation in any of the patients. Microneurographic recordings from cutaneous fascicles revealed the presence of normal large-diameter cutaneous mechanoreceptors in hereditary sensory and autonomic neuropathy III. Our results suggest that the complete absence of functional muscle spindles in these patients explains their loss of deep tendon reflexes. Moreover, we suggest that their Ataxic Gait is sensory in origin, due to the loss of functional muscle spindles and hence a compromised sensorimotor control of locomotion.
Martin A. Giese - One of the best experts on this subject based on the ideXlab platform.
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Real-life Gait assessment in degenerative cerebellar ataxia: Toward ecologically valid biomarkers
Neurology, 2020Co-Authors: Winfried Ilg, Jens Seemann, Martin A. Giese, Andreas Traschütz, Ludger Schöls, Dagmar Timmann, Matthis SynofzikAbstract:Objectives With disease-modifying drugs on the horizon for degenerative ataxias, ecologically valid motor biomarkers are highly warranted. In this observational study, we aimed to unravel and validate markers of Ataxic Gait in real life by using wearable sensors. Methods We assessed Gait characteristics of 43 patients with degenerative cerebellar disease (Scale for the Assessment and Rating of Ataxia [SARA] 9.4 ± 3.9) compared with 35 controls by 3 body-worn inertial sensors in 3 conditions: (1) laboratory-based walking; (2) supervised free walking; (3) real-life walking during everyday living (subgroup n = 21). Movement analysis focused on measures of spatiotemporal step variability and movement smoothness. Results A set of Gait variability measures was identified that allowed us to consistently identify Ataxic Gait changes in all 3 conditions. Lateral step deviation and a compound measure of spatial step variability categorized patients vs controls with a discrimination accuracy of 0.86 in real life. Both were highly correlated with clinical ataxia severity (effect size ρ = 0.76). These measures allowed detecting group differences even for patients who differed only 1 point in the clinical SARAposture&Gait subscore, with highest effect sizes for real-life walking (d = 0.67). Conclusions We identified measures of Ataxic Gait that allowed us not only to capture the Gait variability inherent in Ataxic Gait in real life, but also to demonstrate high sensitivity to small differences in disease severity, with the highest effect sizes in real-life walking. They thus represent promising candidates for motor markers for natural history and treatment trials in ecologically valid contexts. Classification of evidence This study provides Class I evidence that a set of Gait variability measures, even if accessed in real life, correlated with the clinical severity of ataxia in patients with degenerative cerebellar disease.
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Towards ecologically valid biomarkers: real-life Gait assessment in cerebellar ataxia
2019Co-Authors: Winfried Ilg, Jens Seemann, Martin A. Giese, Andreas Traschütz, Ludger Schöls, Dagmar Timmann, Matthis SynofzikAbstract:Abstract BACKGROUND With disease-modifying drugs on the horizon for degenerative ataxias, motor biomarkers are highly warranted. While Ataxic Gait and its treatment-induced improvements can be captured in laboratory-based assessments, quantitative markers of Ataxic Gait in real life will help to determine ecologically meaningful improvements. OBJECTIVES To unravel and validate markers of Ataxic Gait in real life by using wearable sensors. METHODS We assessed Gait characteristics of 43 patients with degenerative cerebellar disease (SARA:9.4±3.9) compared to 35 controls by 3 body-worn inertial sensors in three conditions: (1) laboratory-based walking; (2) supervised free walking; (3) real-life walking during everyday living (subgroup n=21). Movement analysis focussed on measures of movement smoothness and spatio-temporal step variability. RESULTS A set of Gait variability measures was identified which allowed to consistently identify Ataxic Gait changes in all three conditions. Lateral step deviation and a compound measure of step length categorized patients against controls in real life with a discrimination accuracy of 0.86. Both were highly correlated with clinical ataxia severity (effect size ρ=0.76). These measures allowed detecting group differences even for patients who differed only 1 point in the SARAp&g subscore, with highest effect sizes for real-life walking (d=0.67). CONCLUSIONS We identified measures of Ataxic Gait that allowed not only to capture the Gait variability inherent in Ataxic Gait in real life, but also demonstrate high sensitivity to small differences in disease severity - with highest effect sizes in real-life walking. They thus represent promising candidates for quantitative motor markers for natural history and treatment trials in ecologically valid contexts.
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Specific influences of cerebellar dysfunctions on Gait.
Brain : a journal of neurology, 2007Co-Authors: Winfried Ilg, Heidrun Golla, Peter Thier, Martin A. GieseAbstract:Cerebellar Ataxic Gait is characterized by unsteady movements and variable Gait patterns. Previous studies have successfully identified pathological changes of balance-related Gait parameters. However, it has been difficult to demonstrate deficits of joint coordination and the control of limb dynamics. This has motivated the hypothesis that cerebellar Ataxic Gait might be affected predominantly by balance impairments. We investigated the influences of different types of cerebellar dysfunction on the Gait patterns of patients suffering from degenerative cerebellar disease (13 patients, five females, 50.4 +/- 14.4 years). Walking patterns were quantitatively analysed combining standard Gait measures and novel measures for the characterization of the spatial and the temporal variability of intra-joint coordination patterns. The temporal variability of Gait patterns was significantly correlated with a subscale of the clinical ataxia scale (ICARS) that rates deficits of the control of limb dynamics and intra-limb coordination for goal-directed movements. This suggests that common cerebellar mechanisms might be involved in coordination during voluntary limb control and Ataxic Gait. The tested standard Gait parameters correlated predominantly with clinical measures for balance-related abnormalities. These results imply that Ataxic Gait is influenced by both balance-related impairments and deficits related to limb control and intra-limb coordination. Applying the same analysis to Gait patterns from patients with peripheral vestibular failure (six patients, four females, 47.8 +/- 14.3 years) and Parkinson's disease (eight patients, two females, 60.7 +/- 10.6 years), we found comparable abnormalities in balance-related Gait parameters and general Gait variability, but significantly lower increases of temporal variability. This implies that increased temporal variability of intra-limb coordination is a specific characteristic of cerebellar dysfunction, which does not arise for other movement disorders that also cause balance deficits and increased Gait variability.
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Specific influences of cerebellar dysfunctions on Gait.
Brain, 2007Co-Authors: Winfried Ilg, Heidrun Golla, Peter Thier, Martin A. GieseAbstract:successfully identified pathological changes of balance-related Gait parameters. However, it has been difficult to demonstrate deficits of joint coordination and the control of limb dynamics. This has motivated the hypothesis that cerebellar Ataxic Gait might be affected predominantly by balance impairments. We investigated the influences of different types of cerebellar dysfunction on the Gait patterns of patients suffering from degenerative cerebellar disease (13 patients, five females, 50.4 � 14.4 years). Walking patterns were quantitatively analysed combining standard Gait measures and novel measures for the characterization of the spatial and the temporal variability of intra-joint coordination patterns. The temporal variability of Gait patterns was significantly correlated with a subscale of the clinical ataxia scale (ICARS) that rates deficits of the control of limb dynamics and intra-limb coordination for goal-directed movements.This suggests that common cerebellar mechanisms might be involved in coordination during voluntary limb control and Ataxic Gait. The tested standard Gait parameters correlated predominantly with clinical measures for balance-related abnormalities. These results imply that Ataxic Gait is influenced by both balance-related impairments and deficits related to limb control and intralimb coordination. Applying the same analysis to Gait patterns from patients with peripheral vestibular failure (six patients, four females, 47.8 � 14.3 years) and Parkinson’s disease (eight patients, two females, 60.7 � 10.6 years), we found comparable abnormalities in balance-related Gait parameters and general Gait variability, but significantly lower increases of temporal variability.This implies that increased temporal variability of intra-limb coordination is a specific characteristic of cerebellar dysfunction, which does not arise for other movement disorders that also cause balance deficits and increased Gait variability.
Akira Matsushima - One of the best experts on this subject based on the ideXlab platform.
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principal component analysis for Ataxic Gait using a triaxial accelerometer
Journal of Neuroengineering and Rehabilitation, 2017Co-Authors: Akira Matsushima, Kunihiro Yoshida, Hirokazu Genno, Shuichi IkedaAbstract:It is quite difficult to evaluate Ataxic Gait quantitatively in clinical practice. The aim of this study was to analyze the characteristics of Ataxic Gait using a triaxial accelerometer and to develop a novel biomarker of integrated gate parameters for Ataxic Gait. Sixty-one patients with spinocerebellar ataxia (SCA) or multiple system atrophy with predominant cerebellar ataxia (MSA-C) and 57 healthy control subjects were enrolled. The subjects were instructed to walk 10 m for a total of 12 times on a flat floor at their usual walking speed with a triaxial accelerometer attached to their back. Gait velocity, cadence, step length, step regularity, step symmetry, and degree of body sway were evaluated. Principal component analysis (PCA) was used to analyze the multivariate Gait parameters. The Scale for the Assessment and Rating of Ataxia (SARA) was evaluated on the same day of the 10-m walk trial. PCA divided the Gait parameters into four principal components in the controls and into two principal components in the patients. The four principal components in the controls were similar to those found in earlier studies. The second principal component in the patients had relevant factor loading values for Gait velocity, step length, regularity, and symmetry in addition to the degree of body sway in the medio-lateral direction. The second principal component score (PCS) in the patients was significantly correlated with disease duration and the SARA score of Gait (ρ = −0.363, p = 0.004; ρ = −0.574, p < 0.001, respectively). PCA revealed the main component of Ataxic Gait. The PCS of the main component was significantly different between the patients and controls, and it was well correlated with disease duration and the SARA score of Gait in the patients. We propose that this score provides a novel method to assess the severity of Ataxic Gait quantitatively using a triaxial accelerometer.
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Principal component analysis for Ataxic Gait using a triaxial accelerometer.
Journal of neuroengineering and rehabilitation, 2017Co-Authors: Akira Matsushima, Kunihiro Yoshida, Genno Hirokazu, Shuichi IkedaAbstract:It is quite difficult to evaluate Ataxic Gait quantitatively in clinical practice. The aim of this study was to analyze the characteristics of Ataxic Gait using a triaxial accelerometer and to develop a novel biomarker of integrated gate parameters for Ataxic Gait. Sixty-one patients with spinocerebellar ataxia (SCA) or multiple system atrophy with predominant cerebellar ataxia (MSA-C) and 57 healthy control subjects were enrolled. The subjects were instructed to walk 10 m for a total of 12 times on a flat floor at their usual walking speed with a triaxial accelerometer attached to their back. Gait velocity, cadence, step length, step regularity, step symmetry, and degree of body sway were evaluated. Principal component analysis (PCA) was used to analyze the multivariate Gait parameters. The Scale for the Assessment and Rating of Ataxia (SARA) was evaluated on the same day of the 10-m walk trial. PCA divided the Gait parameters into four principal components in the controls and into two principal components in the patients. The four principal components in the controls were similar to those found in earlier studies. The second principal component in the patients had relevant factor loading values for Gait velocity, step length, regularity, and symmetry in addition to the degree of body sway in the medio-lateral direction. The second principal component score (PCS) in the patients was significantly correlated with disease duration and the SARA score of Gait (ρ = −0.363, p = 0.004; ρ = −0.574, p
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Principal component analysis for Ataxic Gait using a triaxial accelerometer
BMC, 2017Co-Authors: Akira Matsushima, Kunihiro Yoshida, Hirokazu Genno, Shuichi IkedaAbstract:Abstract Background It is quite difficult to evaluate Ataxic Gait quantitatively in clinical practice. The aim of this study was to analyze the characteristics of Ataxic Gait using a triaxial accelerometer and to develop a novel biomarker of integrated gate parameters for Ataxic Gait. Methods Sixty-one patients with spinocerebellar ataxia (SCA) or multiple system atrophy with predominant cerebellar ataxia (MSA-C) and 57 healthy control subjects were enrolled. The subjects were instructed to walk 10 m for a total of 12 times on a flat floor at their usual walking speed with a triaxial accelerometer attached to their back. Gait velocity, cadence, step length, step regularity, step symmetry, and degree of body sway were evaluated. Principal component analysis (PCA) was used to analyze the multivariate Gait parameters. The Scale for the Assessment and Rating of Ataxia (SARA) was evaluated on the same day of the 10-m walk trial. Results PCA divided the Gait parameters into four principal components in the controls and into two principal components in the patients. The four principal components in the controls were similar to those found in earlier studies. The second principal component in the patients had relevant factor loading values for Gait velocity, step length, regularity, and symmetry in addition to the degree of body sway in the medio-lateral direction. The second principal component score (PCS) in the patients was significantly correlated with disease duration and the SARA score of Gait (ρ = −0.363, p = 0.004; ρ = −0.574, p
Winfried Ilg - One of the best experts on this subject based on the ideXlab platform.
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Real-life Gait assessment in degenerative cerebellar ataxia: Toward ecologically valid biomarkers
Neurology, 2020Co-Authors: Winfried Ilg, Jens Seemann, Martin A. Giese, Andreas Traschütz, Ludger Schöls, Dagmar Timmann, Matthis SynofzikAbstract:Objectives With disease-modifying drugs on the horizon for degenerative ataxias, ecologically valid motor biomarkers are highly warranted. In this observational study, we aimed to unravel and validate markers of Ataxic Gait in real life by using wearable sensors. Methods We assessed Gait characteristics of 43 patients with degenerative cerebellar disease (Scale for the Assessment and Rating of Ataxia [SARA] 9.4 ± 3.9) compared with 35 controls by 3 body-worn inertial sensors in 3 conditions: (1) laboratory-based walking; (2) supervised free walking; (3) real-life walking during everyday living (subgroup n = 21). Movement analysis focused on measures of spatiotemporal step variability and movement smoothness. Results A set of Gait variability measures was identified that allowed us to consistently identify Ataxic Gait changes in all 3 conditions. Lateral step deviation and a compound measure of spatial step variability categorized patients vs controls with a discrimination accuracy of 0.86 in real life. Both were highly correlated with clinical ataxia severity (effect size ρ = 0.76). These measures allowed detecting group differences even for patients who differed only 1 point in the clinical SARAposture&Gait subscore, with highest effect sizes for real-life walking (d = 0.67). Conclusions We identified measures of Ataxic Gait that allowed us not only to capture the Gait variability inherent in Ataxic Gait in real life, but also to demonstrate high sensitivity to small differences in disease severity, with the highest effect sizes in real-life walking. They thus represent promising candidates for motor markers for natural history and treatment trials in ecologically valid contexts. Classification of evidence This study provides Class I evidence that a set of Gait variability measures, even if accessed in real life, correlated with the clinical severity of ataxia in patients with degenerative cerebellar disease.
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Towards ecologically valid biomarkers: real-life Gait assessment in cerebellar ataxia
2019Co-Authors: Winfried Ilg, Jens Seemann, Martin A. Giese, Andreas Traschütz, Ludger Schöls, Dagmar Timmann, Matthis SynofzikAbstract:Abstract BACKGROUND With disease-modifying drugs on the horizon for degenerative ataxias, motor biomarkers are highly warranted. While Ataxic Gait and its treatment-induced improvements can be captured in laboratory-based assessments, quantitative markers of Ataxic Gait in real life will help to determine ecologically meaningful improvements. OBJECTIVES To unravel and validate markers of Ataxic Gait in real life by using wearable sensors. METHODS We assessed Gait characteristics of 43 patients with degenerative cerebellar disease (SARA:9.4±3.9) compared to 35 controls by 3 body-worn inertial sensors in three conditions: (1) laboratory-based walking; (2) supervised free walking; (3) real-life walking during everyday living (subgroup n=21). Movement analysis focussed on measures of movement smoothness and spatio-temporal step variability. RESULTS A set of Gait variability measures was identified which allowed to consistently identify Ataxic Gait changes in all three conditions. Lateral step deviation and a compound measure of step length categorized patients against controls in real life with a discrimination accuracy of 0.86. Both were highly correlated with clinical ataxia severity (effect size ρ=0.76). These measures allowed detecting group differences even for patients who differed only 1 point in the SARAp&g subscore, with highest effect sizes for real-life walking (d=0.67). CONCLUSIONS We identified measures of Ataxic Gait that allowed not only to capture the Gait variability inherent in Ataxic Gait in real life, but also demonstrate high sensitivity to small differences in disease severity - with highest effect sizes in real-life walking. They thus represent promising candidates for quantitative motor markers for natural history and treatment trials in ecologically valid contexts.
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Specific influences of cerebellar dysfunctions on Gait.
Brain : a journal of neurology, 2007Co-Authors: Winfried Ilg, Heidrun Golla, Peter Thier, Martin A. GieseAbstract:Cerebellar Ataxic Gait is characterized by unsteady movements and variable Gait patterns. Previous studies have successfully identified pathological changes of balance-related Gait parameters. However, it has been difficult to demonstrate deficits of joint coordination and the control of limb dynamics. This has motivated the hypothesis that cerebellar Ataxic Gait might be affected predominantly by balance impairments. We investigated the influences of different types of cerebellar dysfunction on the Gait patterns of patients suffering from degenerative cerebellar disease (13 patients, five females, 50.4 +/- 14.4 years). Walking patterns were quantitatively analysed combining standard Gait measures and novel measures for the characterization of the spatial and the temporal variability of intra-joint coordination patterns. The temporal variability of Gait patterns was significantly correlated with a subscale of the clinical ataxia scale (ICARS) that rates deficits of the control of limb dynamics and intra-limb coordination for goal-directed movements. This suggests that common cerebellar mechanisms might be involved in coordination during voluntary limb control and Ataxic Gait. The tested standard Gait parameters correlated predominantly with clinical measures for balance-related abnormalities. These results imply that Ataxic Gait is influenced by both balance-related impairments and deficits related to limb control and intra-limb coordination. Applying the same analysis to Gait patterns from patients with peripheral vestibular failure (six patients, four females, 47.8 +/- 14.3 years) and Parkinson's disease (eight patients, two females, 60.7 +/- 10.6 years), we found comparable abnormalities in balance-related Gait parameters and general Gait variability, but significantly lower increases of temporal variability. This implies that increased temporal variability of intra-limb coordination is a specific characteristic of cerebellar dysfunction, which does not arise for other movement disorders that also cause balance deficits and increased Gait variability.
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Specific influences of cerebellar dysfunctions on Gait.
Brain, 2007Co-Authors: Winfried Ilg, Heidrun Golla, Peter Thier, Martin A. GieseAbstract:successfully identified pathological changes of balance-related Gait parameters. However, it has been difficult to demonstrate deficits of joint coordination and the control of limb dynamics. This has motivated the hypothesis that cerebellar Ataxic Gait might be affected predominantly by balance impairments. We investigated the influences of different types of cerebellar dysfunction on the Gait patterns of patients suffering from degenerative cerebellar disease (13 patients, five females, 50.4 � 14.4 years). Walking patterns were quantitatively analysed combining standard Gait measures and novel measures for the characterization of the spatial and the temporal variability of intra-joint coordination patterns. The temporal variability of Gait patterns was significantly correlated with a subscale of the clinical ataxia scale (ICARS) that rates deficits of the control of limb dynamics and intra-limb coordination for goal-directed movements.This suggests that common cerebellar mechanisms might be involved in coordination during voluntary limb control and Ataxic Gait. The tested standard Gait parameters correlated predominantly with clinical measures for balance-related abnormalities. These results imply that Ataxic Gait is influenced by both balance-related impairments and deficits related to limb control and intralimb coordination. Applying the same analysis to Gait patterns from patients with peripheral vestibular failure (six patients, four females, 47.8 � 14.3 years) and Parkinson’s disease (eight patients, two females, 60.7 � 10.6 years), we found comparable abnormalities in balance-related Gait parameters and general Gait variability, but significantly lower increases of temporal variability.This implies that increased temporal variability of intra-limb coordination is a specific characteristic of cerebellar dysfunction, which does not arise for other movement disorders that also cause balance deficits and increased Gait variability.