News
An evaluation of the Wolf Motor Function Test in motor trials early after stroke.
Arch Phys Med Rehabil. 2012 Apr;93(4):660-8
Authors: Edwards DF, Lang CE, Wagner JM, Birkenmeier R, Dromerick AW
Abstract
OBJECTIVE: To examine the internal consistency, validity, responsiveness, and advantages of the Wolf Motor Function Test (WMFT) and compare these results to the Action Research Arm Test (ARAT) in participants with mild to moderate hemiparesis within the first few months after stroke.
DESIGN: Data were collected as part of the Very Early Constraint-Induced Therapy for Recovery from Stroke (VECTORS) trial, an acute, single-blind randomized controlled trial of constraint-induced movement therapy. Subjects were studied at baseline (day 0), after treatment (day 14), and after 90 days (day 90) poststroke.
SETTING: Inpatient rehabilitation hospital; follow-up 3 months poststroke.
PARTICIPANTS: Hemiparetic subjects (N=51) enrolled in the VECTORS trial.
INTERVENTION: None.
MAIN OUTCOME MEASURES: At each time point, subjects were tested on (1) the WMFT and ARAT, (2) clinical measures of sensorimotor impairments, (3) reach and grasp movements performed in the kinematics laboratory, and (4) clinical measures of disability. Blinded raters performed all evaluations. Analyses at each time point included calculating effect size as indicators of responsiveness, and correlation analyses to examine relationships between WMFT scores and other measures.
RESULTS: The WMFT is internally consistent, valid, and responsive in the early stages of stroke recovery. Sensorimotor and kinematic measures of reach and grasp support the construct validity of the WMFT.
CONCLUSIONS: In an acute stroke population, the WMFT has acceptable reliability, validity, and responsiveness to change over time. However, when compared with the ARAT, the higher training and testing burdens may not be offset by the relatively small psychometric advantages.
PMID: 22336104 [PubMed - indexed for MEDLINE]
J Neuroeng Rehabil. 2012;9:6
Authors: Zimmerli L, Krewer C, Gassert R, Müller F, Riener R, Lünenburger L
Abstract
BACKGROUND: The motivation of patients during robot-assisted rehabilitation after neurological disorders that lead to impairments of motor functions is of great importance. Due to the increasing number of patients, increasing medical costs and limited therapeutic resources, clinicians in the future may want patients to practice their movements at home or with reduced supervision during their stay in the clinic. Since people only engage in an activity and are motivated to practice if the outcome matches the effort at which they perform, an augmented feedback application for rehabilitation should take the cognitive and physical deficits of patients into account and incorporate a mechanism that is capable of balancing i.e. adjusting the difficulty of an exercise in an augmented feedback application to the patient's capabilities.
METHODS: We propose a computational mechanism based on Fitts' Law that balances i.e. adjusts the difficulty of an exercise for upper-extremity rehabilitation. The proposed mechanism was implemented into an augmented feedback application consisting of three difficulty conditions (easy, balanced, hard). The task of the exercise was to reach random targets on the screen from a starting point within a specified time window. The available time was decreased with increasing condition difficulty. Ten subacute stroke patients were recruited to validate the mechanism through a study. Cognitive and motor functions of patients were assessed using the upper extremity section of the Fugl-Meyer Assessment, the modified Ashworth scale as well as the Addenbrookes cognitive examination-revised. Handedness of patients was obtained using the Edinburgh handedness inventory. Patients' performance during the execution of the exercises was measured twice, once for the paretic and once for the non-paretic arm. Results were compared using a two-way ANOVA. Post hoc analysis was performed using a Tukey HSD with a significance level of p < 0.05.
RESULTS: Results show that the mechanism was capable of balancing the difficulty of an exercise to the capabilities of the patients. Medians for both arms show a gradual decrease and significant difference of the number of successful trials with increasing condition difficulty (F(2;60) = 44.623; p < 0.01; η(2) = 0.623) but no significant difference between paretic and non-paretic arm (F(1;60) = 3.768; p = 0.057; η(2) = 0.065). Post hoc analysis revealed that, for both arms, the hard condition significantly differed from the easy condition (p < 0.01). In the non-paretic arm there was an additional significant difference between the balanced and the hard condition (p < 0.01). Reducing the time to reach the target, i.e., increasing the difficulty level, additionally revealed significant differences between conditions for movement speeds (F(2;59) = 6.013; p < 0.01; η(2) = 0.185), without significant differences for hand-closing time (F(2;59) = 2.620; p = 0.082; η(2) = 0.09), reaction time (F(2;59) = 0.978; p = 0.383; η(2) = 0.036) and hand-path ratio (F(2;59) = 0.054; p = 0.947; η(2) = 0.002). The evaluation of a questionnaire further supported the assumption that perceived performance declined with increased effort and increased exercise difficulty leads to frustration.
CONCLUSIONS: Our results support that Fitts' Law indeed constitutes a powerful mechanism for task difficulty adaptation and can be incorporated into exercises for upper-extremity rehabilitation.
PMID: 22304989 [PubMed - indexed for MEDLINE]
Dry-land strength training vs. electrical stimulation in sprint swimming performance.
J Strength Cond Res. 2012 Feb;26(2):497-505
Authors: Girold S, Jalab C, Bernard O, Carette P, Kemoun G, Dugué B
Abstract
This study was undertaken to compare the effects of dry-land strength training vs. an electrical stimulation program on swimmers. Twenty-four national-level swimmers were randomly assigned to 3 groups: the dry-land strength training program (S), the electrical stimulation training program (ES), and the control (C) group. The training program lasted 4 weeks. The subjects were evaluated before the training, at the end of the training program, and 4 weeks later. The outcome values ascertained were peak torque during arm extension at different velocities (from -60 to 180°·s(-1)) using an isokinetic dynamometer and performance, stroke rate, and stroke length during a 50-m front crawl. A significant increase in swimming velocity and peak torque was observed for both S and ES at the end of the training and 4 weeks later. Stroke length increased in the S group but not in the ES group. However, no significant differences in swimming velocity between S and ES groups were observed. No significant changes occurred in the C group. Programs combining swimming training with dry-land strength or electrical stimulation programs led to a similar gain in sprint performance and were more efficient than swimming alone.
PMID: 22233789 [PubMed - indexed for MEDLINE]
Phys Ther. 2012 Apr;92(4):483-92
Authors: Wu CY, Chen YA, Lin KC, Chao CP, Chen YT
Abstract
BACKGROUND: Studies have suggested that constraint-induced therapy combined with trunk restraint (CIT-TR) improves arm movement and reduces trunk compensation. Whether participants who receive CIT-TR can translate the benefits to real-life circumstances awaits further investigation.
OBJECTIVE: The effects of distributed CIT-TR (dCIT-TR) on motor function, daily function, quality of life (QOL), and arm-trunk control were investigated.
DESIGN: The study was a single-blind, randomized controlled trial.
SETTING: The study took place at 4 hospitals.
PARTICIPANTS: Participants were 57 people who had had a stroke 6 to 55 months earlier.
INTERVENTION: Participants received a dose-matched intervention (2 hours per day, 5 days per week, for 3 weeks) of dCIT-TR, distributed constraint-induced therapy (dCIT), or control therapy.
MEASUREMENTS: The Action Research Arm Test (ARAT), Motor Activity Log, Frenchay Activities Index (FAI), and Stroke Impact Scale (SIS) were used to evaluate motor function, daily function, and QOL. Data for reaching kinematics were recorded.
RESULTS: Participants receiving dCIT-TR and dCIT exhibited higher overall scores on the ARAT, FAI, and hand function domain of the SIS and better quality of movement and larger amount of use (of the affected arm) on the Motor Activity Log than participants in the control group. Participants receiving dCIT-TR further demonstrated greater improvements on the ARAT grip subscale and FAI outdoor activities scale than participants receiving dCIT or participants in the control group. However, participants receiving dCIT showed greater improvements on the strength domain of the SIS after training than participants receiving dCIT-TR or participants in the control group. Limitations Research with a larger sample size is needed.
CONCLUSIONS: Participants who received dCIT-TR were able to translate gains in arm-trunk control into functional performance and QOL, specifically in grip function and outdoor activities. A long-term study to examine the recovery course for force output may be needed to evaluate people's perception of less improvement in strength after dCIT-TR.
PMID: 22228607 [PubMed - indexed for MEDLINE]
Selectivity and resolution of surface electrical stimulation for grasp and release.
IEEE Trans Neural Syst Rehabil Eng. 2012 Jan;20(1):94-101
Authors: Westerveld AJ, Schouten AC, Veltink PH, van der Kooij H
Abstract
Electrical stimulation of arm and hand muscles can be a functional tool for patients with motor dysfunction. Sufficient stimulation of finger and thumb musculature can support natural grasping function. Yet it remains unclear how different grasping movements can be selectively supported by electrical stimulation. The goal of this study is to determine to what extent activation of individual fingers is possible with surface electrical stimulation for the purpose of rehabilitation following stroke. The extensor digitorum communis (EDC) muscle, flexor pollicis longus (FPL) muscle, and the thenar muscle group, all involved in grasp and release, were selected for stimulation. The evoked forces in individual fingers were measured. Stimulation thresholds and selective ranges were determined for each subject. Electrode locations where the highest selective range occurred were compared between subjects and influences of different isometric wrist positions were assessed. In all subjects selective stimulation of middle finger extension and thumb flexion was possible. In addition, selective stimulation of index and ring finger extension was possible in most cases. In nine out of the ten EDC subjects we were able to stimulate three or all four fingers selectively. However, large variability in electrode locations for high selectivity was observed between the subjects. Within the designs of grasping prostheses and grasping rehabilitation devices, the variability of electrode locations should be taken into account. The results of our study facilitate the optimization of such designs and favour a design which allows individualized stimulation locations.
PMID: 22180518 [PubMed - indexed for MEDLINE]