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A novel method for the quantification of key components of manual dexterity after stroke.

Térémetz M, Colle F, Hamdoun S, Maier MA, Lindberg PG - J Neuroeng Rehabil (2015)

Bottom Line: Four FFM tasks were used: (1) Finger Force Tracking to measure force control, (2) Sequential Finger Tapping to measure the ability to perform motor sequences, (3) Single Finger Tapping to measure timing effects, and (4) Multi-Finger Tapping to measure the ability to selectively move fingers in specified combinations (independence of finger movements).Patients showed less accurate force control, reduced tapping rate, and reduced independence of finger movements compared to controls.Quantifying some of the key components of manual dexterity with the FFM is feasible in moderately affected hemiparetic patients.

View Article: PubMed Central - PubMed

Affiliation: FR3636 CNRS, Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France. mteremetz@gmail.com.

ABSTRACT

Background: A high degree of manual dexterity is a central feature of the human upper limb. A rich interplay of sensory and motor components in the hand and fingers allows for independent control of fingers in terms of timing, kinematics and force. Stroke often leads to impaired hand function and decreased manual dexterity, limiting activities of daily living and impacting quality of life. Clinically, there is a lack of quantitative multi-dimensional measures of manual dexterity. We therefore developed the Finger Force Manipulandum (FFM), which allows quantification of key components of manual dexterity. The purpose of this study was (i) to test the feasibility of using the FFM to measure key components of manual dexterity in hemiparetic stroke patients, (ii) to compare differences in dexterity components between stroke patients and controls, and (iii) to describe individual profiles of dexterity components in stroke patients.

Methods: 10 stroke patients with mild-to-moderate hemiparesis and 10 healthy subjects were recruited. Clinical measures of hand function included the Action Research Arm Test and the Moberg Pick-Up Test. Four FFM tasks were used: (1) Finger Force Tracking to measure force control, (2) Sequential Finger Tapping to measure the ability to perform motor sequences, (3) Single Finger Tapping to measure timing effects, and (4) Multi-Finger Tapping to measure the ability to selectively move fingers in specified combinations (independence of finger movements).

Results: Most stroke patients could perform the tracking task, as well as the single and multi-finger tapping tasks. However, only four patients performed the sequence task. Patients showed less accurate force control, reduced tapping rate, and reduced independence of finger movements compared to controls. Unwanted (erroneous) finger taps and overflow to non-tapping fingers were increased in patients. Dexterity components were not systematically related among each other, resulting in individually different profiles of deficient dexterity. Some of the FFM measures correlated with clinical scores.

Conclusions: Quantifying some of the key components of manual dexterity with the FFM is feasible in moderately affected hemiparetic patients. The FFM can detect group differences and individual profiles of deficient dexterity. The FFM is a promising tool for the measurement of key components of manual dexterity after stroke and could allow improved targeting of motor rehabilitation.

No MeSH data available.


Related in: MedlinePlus

Individual dexterity profiles. a-b Force tracking, C-D) Single finger tapping, e-f) Multi-finger tapping. a Index finger force tracking: mean error score for each stroke patient (P01-P10). The ‘normality threshold’ (control average + 2SD) is indicated by a horizontal line (and its corresponding value). Individual scores > threshold were considered pathological. b Index finger force tracking: mean release duration. c Single finger tapping rate: 1 minus the slope 1-3Hz value for the index finger for each patient. d Single finger tapping: number of overflow taps during the 1Hz condition. e Multi-finger tapping: omission rate across all trials. f Multi-finger tapping: number of unwanted extra-finger-taps (UEFTs) for one-finger combination trials. Patient P01 did not perform this task
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Fig8: Individual dexterity profiles. a-b Force tracking, C-D) Single finger tapping, e-f) Multi-finger tapping. a Index finger force tracking: mean error score for each stroke patient (P01-P10). The ‘normality threshold’ (control average + 2SD) is indicated by a horizontal line (and its corresponding value). Individual scores > threshold were considered pathological. b Index finger force tracking: mean release duration. c Single finger tapping rate: 1 minus the slope 1-3Hz value for the index finger for each patient. d Single finger tapping: number of overflow taps during the 1Hz condition. e Multi-finger tapping: omission rate across all trials. f Multi-finger tapping: number of unwanted extra-finger-taps (UEFTs) for one-finger combination trials. Patient P01 did not perform this task

Mentions: Individual profiles were investigated in six measures found to differ significantly between groups. From the tracking task we studied error and release duration. From the single-finger tapping task, slope of tapping rate and number of overflow taps were retained. And from the multi-finger tapping task, omission rate and frequency of unwanted extra-finger-taps were assessed. Although significant group differences were found in several dexterity components, not all measures were pathological in all patients (above mean + 2SD threshold). For example, only 6 (of 10) patients showed pathological tracking error (Fig. 8a). Furthermore, only 3 patients (P03, P05, P06) showed pathological scores in all 6 measures. Thus, the presence of a pathological score in one variable did not always coincide with the presence of pathological scores in other measures. Neither did absence of one pathological score indicate absence in all other scores. The most common profile (in 4 patients) was a combination of five affected dexterity components: release duration, tracking error, number of overflow taps, omission rate and unwanted extra-finger-taps. These five components were increased compared to control thresholds.Fig. 8


A novel method for the quantification of key components of manual dexterity after stroke.

Térémetz M, Colle F, Hamdoun S, Maier MA, Lindberg PG - J Neuroeng Rehabil (2015)

Individual dexterity profiles. a-b Force tracking, C-D) Single finger tapping, e-f) Multi-finger tapping. a Index finger force tracking: mean error score for each stroke patient (P01-P10). The ‘normality threshold’ (control average + 2SD) is indicated by a horizontal line (and its corresponding value). Individual scores > threshold were considered pathological. b Index finger force tracking: mean release duration. c Single finger tapping rate: 1 minus the slope 1-3Hz value for the index finger for each patient. d Single finger tapping: number of overflow taps during the 1Hz condition. e Multi-finger tapping: omission rate across all trials. f Multi-finger tapping: number of unwanted extra-finger-taps (UEFTs) for one-finger combination trials. Patient P01 did not perform this task
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4522286&req=5

Fig8: Individual dexterity profiles. a-b Force tracking, C-D) Single finger tapping, e-f) Multi-finger tapping. a Index finger force tracking: mean error score for each stroke patient (P01-P10). The ‘normality threshold’ (control average + 2SD) is indicated by a horizontal line (and its corresponding value). Individual scores > threshold were considered pathological. b Index finger force tracking: mean release duration. c Single finger tapping rate: 1 minus the slope 1-3Hz value for the index finger for each patient. d Single finger tapping: number of overflow taps during the 1Hz condition. e Multi-finger tapping: omission rate across all trials. f Multi-finger tapping: number of unwanted extra-finger-taps (UEFTs) for one-finger combination trials. Patient P01 did not perform this task
Mentions: Individual profiles were investigated in six measures found to differ significantly between groups. From the tracking task we studied error and release duration. From the single-finger tapping task, slope of tapping rate and number of overflow taps were retained. And from the multi-finger tapping task, omission rate and frequency of unwanted extra-finger-taps were assessed. Although significant group differences were found in several dexterity components, not all measures were pathological in all patients (above mean + 2SD threshold). For example, only 6 (of 10) patients showed pathological tracking error (Fig. 8a). Furthermore, only 3 patients (P03, P05, P06) showed pathological scores in all 6 measures. Thus, the presence of a pathological score in one variable did not always coincide with the presence of pathological scores in other measures. Neither did absence of one pathological score indicate absence in all other scores. The most common profile (in 4 patients) was a combination of five affected dexterity components: release duration, tracking error, number of overflow taps, omission rate and unwanted extra-finger-taps. These five components were increased compared to control thresholds.Fig. 8

Bottom Line: Four FFM tasks were used: (1) Finger Force Tracking to measure force control, (2) Sequential Finger Tapping to measure the ability to perform motor sequences, (3) Single Finger Tapping to measure timing effects, and (4) Multi-Finger Tapping to measure the ability to selectively move fingers in specified combinations (independence of finger movements).Patients showed less accurate force control, reduced tapping rate, and reduced independence of finger movements compared to controls.Quantifying some of the key components of manual dexterity with the FFM is feasible in moderately affected hemiparetic patients.

View Article: PubMed Central - PubMed

Affiliation: FR3636 CNRS, Université Paris Descartes, Sorbonne Paris Cité, 75006, Paris, France. mteremetz@gmail.com.

ABSTRACT

Background: A high degree of manual dexterity is a central feature of the human upper limb. A rich interplay of sensory and motor components in the hand and fingers allows for independent control of fingers in terms of timing, kinematics and force. Stroke often leads to impaired hand function and decreased manual dexterity, limiting activities of daily living and impacting quality of life. Clinically, there is a lack of quantitative multi-dimensional measures of manual dexterity. We therefore developed the Finger Force Manipulandum (FFM), which allows quantification of key components of manual dexterity. The purpose of this study was (i) to test the feasibility of using the FFM to measure key components of manual dexterity in hemiparetic stroke patients, (ii) to compare differences in dexterity components between stroke patients and controls, and (iii) to describe individual profiles of dexterity components in stroke patients.

Methods: 10 stroke patients with mild-to-moderate hemiparesis and 10 healthy subjects were recruited. Clinical measures of hand function included the Action Research Arm Test and the Moberg Pick-Up Test. Four FFM tasks were used: (1) Finger Force Tracking to measure force control, (2) Sequential Finger Tapping to measure the ability to perform motor sequences, (3) Single Finger Tapping to measure timing effects, and (4) Multi-Finger Tapping to measure the ability to selectively move fingers in specified combinations (independence of finger movements).

Results: Most stroke patients could perform the tracking task, as well as the single and multi-finger tapping tasks. However, only four patients performed the sequence task. Patients showed less accurate force control, reduced tapping rate, and reduced independence of finger movements compared to controls. Unwanted (erroneous) finger taps and overflow to non-tapping fingers were increased in patients. Dexterity components were not systematically related among each other, resulting in individually different profiles of deficient dexterity. Some of the FFM measures correlated with clinical scores.

Conclusions: Quantifying some of the key components of manual dexterity with the FFM is feasible in moderately affected hemiparetic patients. The FFM can detect group differences and individual profiles of deficient dexterity. The FFM is a promising tool for the measurement of key components of manual dexterity after stroke and could allow improved targeting of motor rehabilitation.

No MeSH data available.


Related in: MedlinePlus