A study of predictive validity, responsiveness, and minimal clinically important difference of arm accelerometer in real-world activity of patients with chronic stroke.

OBJECTIVE: To investigate the predictive validity, responsiveness, and minimal clinically important difference of arm accelerometer in real-world activity of patients with chronic stroke. DESIGN: Validation and psychometric study. SETTING: Three medical centers. SUBJECTS: Patients with chronic stroke came from three separated randomized controlled trials. INTERVENTIONS: Patients with stroke received upper extremity rehabilitation programs for four weeks. MAIN MEASURES: Real-world arm movements were measured by an arm accelerometer and three clinical measurement tools-the Motor Activity Log, Stroke Impact Scale, and Nottingham Extended Activities of Daily Living-administered before and after treatment. RESULTS: A total of 82 subjects were recruited in the study (mean age: 55.32 years; mean score of Fugl-Meyer Assessment: 39.91). Correlations between the arm accelerometer and three clinical measurement tools were fair to moderate (Pearson's r = 0.47, 0.42, and 0.34, respectively). The correlation between the arm accelerometer and the quality of use of Motor Activity Log subscale was moderate to good (Pearson's r = 0.57). The responsiveness of the arm accelerometer from pretreatment to posttreatment was medium (standardized response mean = 0.72). The minimal clinically important difference range for the arm accelerometer was 547-751 mean counts. CONCLUSION: The arm accelerometer demonstrated acceptable predictive validity and responsiveness in patients with chronic stroke. The affected arm activity measured by the arm accelerometer was sensitive to change. The change score of a patient with chronic stroke on the arm accelerometer should reach 574-751 mean counts to be regarded as a minimal clinically important difference.

Sequencing bilateral robot-assisted arm therapy and constraint-induced therapy improves reach to press and trunk kinematics in patients with stroke.

BACKGROUND: The combination of robot-assisted therapy (RT) and a modified form of constraint-induced therapy (mCIT) shows promise for improving motor function of patients with stroke. However, whether the changes of motor control strategies are concomitant with the improvements in motor function after combination of RT and mCIT (RT + mCIT) is unclear. This study investigated the effects of the sequential combination of RT + mCIT compared with RT alone on the strategies of motor control measured by kinematic analysis and on motor function and daily performance measured by clinical scales. METHODS: The study enrolled 34 patients with chronic stroke. The data were derived from part of a single-blinded randomized controlled trial. Participants in the RT + mCIT and RT groups received 20 therapy sessions (90 to 105 min/day, 5 days for 4 weeks). Patients in the RT + mCIT group received 10 RT sessions for first 2 weeks and 10 mCIT sessions for the next 2 weeks. The Bi-Manu-Track was used in RT sessions to provide bilateral practice of wrist and forearm movements. The primary outcome was kinematic variables in a task of reaching to press a desk bell. Secondary outcomes included scores on the Wolf Motor Function Test, Functional Independence Measure, and Nottingham Extended Activities of Daily Living. All outcome measures were administered before and after intervention. RESULTS: RT + mCIT and RT demonstrated different benefits on motor control strategies. RT + mCIT uniquely improved motor control strategies by reducing shoulder abduction, increasing elbow extension, and decreasing trunk compensatory movement during the reaching task. Motor function and quality of the affected limb was improved, and patients achieved greater independence in instrumental activities of daily living. Force generation at movement initiation was improved in the patients who received RT. CONCLUSION: A combination of RT and mCIT could be an effective approach to improve stroke rehabilitation outcomes, achieving better motor control strategies, motor function, and functional independence of instrumental activities of daily living. TRIAL REGISTRATION: ClinicalTrials.gov. NCT01727648.

Validity, responsiveness, and minimal clinically important difference of EQ-5D-5L in stroke patients undergoing rehabilitation.

PURPOSE: To examine the criterion validity, responsiveness, and minimal clinically important difference (MCID) of the EuroQoL 5-Dimensions Questionnaire (EQ-5D-5L) and visual analog scale (EQ-VAS) in people receiving rehabilitation after stroke. METHODS: The EQ-5D-5L, along with four criterion measures-the Medical Research Council scales for muscle strength, the Fugl-Meyer assessment, the functional independence measure, and the Stroke Impact Scale-was administered to 65 patients with stroke before and after 3- to 4-week therapy. Criterion validity was estimated using the Spearman correlation coefficient. Responsiveness was analyzed by the effect size, standardized response mean (SRM), and criterion responsiveness. The MCID was determined by anchor-based and distribution-based approaches. The percentage of patients exceeding the MCID was also reported. RESULTS: Concurrent validity of the EQ-Index was better compared with the EQ-VAS. The EQ-Index has better power for predicting the rehabilitation outcome in the activities of daily living than other motor-related outcome measures. The EQ-Index was moderately responsive to change (SRM = 0.63), whereas the EQ-VAS was only mildly responsive to change. The MCID estimation of the EQ-Index (the percentage of patients exceeding the MCID) was 0.10 (33.8 %) and 0.10 (33.8 %) based on the anchor-based and distribution-based approaches, respectively, and the estimation of EQ-VAS was 8.61 (41.5 %) and 10.82 (32.3 %). CONCLUSIONS: The EQ-Index has shown reasonable concurrent validity, limited predictive validity, and acceptable responsiveness for detecting the health-related quality of life in stroke patients undergoing rehabilitation, but not for EQ-VAS. Future research considering different recovery stages after stroke is warranted to validate these estimations.

Kinematic measures of Arm-trunk movements during unilateral and bilateral reaching predict clinically important change in perceived arm use in daily activities after intensive stroke rehabilitation.

BACKGROUND: Kinematic analysis has been used to objectively evaluate movement patterns, quality, and strategies during reaching tasks. However, no study has investigated whether kinematic variables during unilateral and bilateral reaching tasks predict a patient's perceived arm use during activities of daily living (ADL) after an intensive intervention. Therefore, this study investigated whether kinematic measures during unilateral and bilateral reaching tasks before an intervention can predict clinically meaningful improvement in perceived arm use during ADL after intensive poststroke rehabilitation. METHODS: The study was a secondary analysis of 120 subjects with chronic stroke who received 90-120 min of intensive intervention every weekday for 3-4 weeks. Reaching kinematics during unilateral and bilateral tasks and the Motor Activity Log (MAL) were evaluated before and after the intervention. RESULTS: Kinematic variables explained 22 and 11 % of the variance in actual amount of use (AOU) and quality of movement (QOM), respectively, of MAL improvement during unilateral reaching tasks. Kinematic variables also explained 21 and 31 % of the variance in MAL-AOU and MAL-QOM, respectively, during bilateral reaching tasks. Selected kinematic variables, including endpoint variables, trunk involvement, and joint recruitment and interjoint coordination, were significant predictors for improvement in perceived arm use during ADL (P < 0.05). CONCLUSIONS: Arm-trunk kinematics may be used to predict clinically meaningful improvement in perceived arm use during ADL after intensive rehabilitation. Involvement of interjoint coordination and trunk control variables as predictors in bilateral reaching models indicates that a high level of motor control (i.e., multijoint coordination) and trunk stability may be important in obtaining treatment gains in arm use, especially for bilateral daily activities, in intensive rehabilitation after stroke.

Concurrent and Predictive Validity of Arm Kinematics With and Without a Trunk Restraint During a Reaching Task in Individuals With Stroke.

OBJECTIVE: To examine the concurrent and predictive validity of measurements of kinematic variables during reaching tasks with and without a trunk constraint in individuals with stroke. DESIGN: Randomized controlled trials. SETTINGS: Hospitals and a laboratory. PARTICIPANTS: Individuals with stroke (N=95) enrolled in previous and ongoing clinical trials. INTERVENTIONS: Upper limb training protocols were 90 to 120 minutes of intervention every weekday for 3 to 4 weeks. MAIN OUTCOME MEASURES: Functional capacity was assessed using the Action Research Arm Test and motor impairment using the Fugl-Meyer Assessment for the Upper Extremity. Movement kinematics were measured during a reaching task with and without a trunk constraint. We derived 5 endpoint control variables and 3 joint recruitment variables for estimating concurrent and predictive validity. RESULTS: The adjusted R(2) values for the constraint tasks ranged from .24 to .38 and for the unconstraint tasks from .29 to .40. Movement time was the most prominent kinematic variable for the Fugl-Meyer Assessment for the Upper Extremity before and after the intervention (P<.05). For the Action Research Arm Test, movement time and endpoint displacement were the most significant variables before and after the intervention, respectively (P<.05). CONCLUSIONS: Measuring kinematic performance during an unconstrained task is appropriate and possibly sufficient to represent motor impairment and functional capacity of individuals with stroke. Movement time is the dominant variable associated with motor impairment and functional capacity, and endpoint displacement is unique in reflecting functional capacity of individuals with stroke.

Arm and trunk movement kinematics during seated reaching within and beyond arm's length in people with stroke: a validity study.

BACKGROUND: Kinematic analysis is commonly used to objectively measure upper extremity movement performance after stroke. However, the concurrent validity and predictive validity of arm-trunk kinematics during reaching within and beyond arm's length have not been studied. OBJECTIVE: The aim of this study was to estimate the concurrent validity of kinematic measures before and after treatment and the predictive validity for reaching within and beyond arm's length after stroke. DESIGN: This was a secondary analysis study. METHODS: Ninety-seven participants with stroke (mean age=55.9 years [SD=10.9]) received intensive treatment every weekday for 3 to 4 weeks. Kinematic reaching tasks and the Wolf Motor Function Test (WMFT) were used before and after treatment. The validity of the kinematic measures was estimated in relation to WMFT scores. RESULTS: Of the 8 kinematic variables that were measured, index movement time before treatment (R2=.227-.362) and trunk movement time and trunk displacement after treatment (R2=.095-.346) had the strongest association with the WMFT at both reaching distances. Trunk movement time and trunk displacement before treatment explained 6.9% to 14.9% of the variance in the WMFT after treatment. Kinematic variables explained 6.9% to 49.3% and 9.4% to 38.7% of the variance in the WMFT during a task within arm's length and beyond arm's length, respectively. LIMITATIONS: The study has limited generalizability. CONCLUSIONS: Different kinematic variables may partially reflect motor function before and after treatment to a limited degree. Although the predictive validity was modest, trunk movement may be considered a prognostic determinant of motor function after treatment. A reaching task within arm's length may be a more suitable measure of kinematic performance for describing motor function than a reaching task beyond arm's length.

Relationship between chest wall motion and diaphragmatic excursion in healthy adults in supine position.

BACKGROUND/PURPOSE: There has been a lack of studies that have used both three-dimensional analysis and imaging tools concurrently to describe lung volume changes and breathing pattern in subjects in the supine position. The purpose of this study was to investigate the correlation between volume changes estimated by optoelectronic plethysmography (OEP) and diaphragmatic excursion (DE) measured by ultrasonography of healthy adults in the supine position. METHODS: Twelve healthy male subjects (age, 25.08 +/- 6.35 years) were recruited and asked to perform tidal and deep breathing in the supine position. The volume changes during chest wall motion were quantified from OEP analysis---this was done for the upper thorax (UT), lower thorax (LT), and abdominal (AB) compartment. Lung volume was measured synchronously via the mouth piece of an electrospirometer. The right diaphragmatic movement was measured by ultrasonography. RESULTS: Linear regression showed that all three compartments (V UT, V LT and V AB) in the inspiratory phase were correlated highly with DE during tidal and deep breathing. However, multiple linear regression analysis showed that the VAB contributed 94-95% of the variance when performing either tidal or deep breathing. A predicted equation for diaphragmatic movement during deep breathing was DE = 0.052 + 0.294 V AB. CONCLUSION: The movement of V AB can be used as an index of DE among the normal population in the supine position. Its application in patients requires further study.