Keh-chung Lin

A kinematic study of contextual effects on reaching performance in persons with and without stroke: influences of object availability.

OBJECTIVE To examine the effects of context on reaching performance in neurologically impaired and intact populations. Context was varied by the presence or absence of objects used to complete a task. DESIGN A counterbalanced repeated-measures design. SETTING A motor control laboratory in a university setting. PARTICIPANTS Fourteen persons with stroke and 25 neurologically intact adults. INTERVENTIONS Each participant was tested under two conditions: the presence of the object, in which the participant reached forward with the impaired arm (or corresponding arm) to scoop coins off the table into the other hand; and the absence of the object, in which the participant reached forward to the place where the coins would be placed in the condition of object present. MAIN OUTCOME MEASURES Kinematic Variables of movement time, total displacement, peak velocity, percentage of reach where peak velocity occurs, and movement units (derived from acceleration data) for reaching tasks. RESULTS The condition of using real objects elicited kinematically better performance of reaching movements than the condition of performing movements without relevant objects present. Better performance was reflected by shorter movement time, less total displacement, higher peak velocity, greater percentage of reach where peak velocity occurs, and fewer movement units. CONCLUSION The results of this study showed that the condition of object present elicited better performance of movements represented by kinematic variables than the condition of object absent. The clinical implication is that the use of real and functional objects might be an effective way of facilitating efficient, smooth, and coordinated movement with the impaired arm in persons with stroke. This study, however, should be replicated and extended to confirm the validity of its findings and to allow for generalization in various functional activities.

Responsiveness and Validity of Three Outcome Measures of Motor Function After Stroke Rehabilitation

Background and Purpose— This study investigated and compared the responsiveness and validity of the Fugl-Meyer Assessment (FMA), the Action Research Arm Test (ARAT), and the Wolf Motor Function Test (WMFT) for patients after stroke rehabilitation. Methods— A total of 57 patients with stroke received 1 of 3 rehabilitation treatments for 3 weeks. At pretreatment and posttreatment, the 3 outcome measures, as well as the Functional Independence Measure (FIM) as the external criterion, were administered. The standardized response mean (SRM) and the Wilcoxon signed rank test were used to examine the responsiveness. Construct validity and predictive validity were examined by the Spearman correlation coefficient (&rgr;). Results— The responsiveness of the FMA, ARAT, and WMFT functional ability scores was large (SRM=0.95–1.42), whereas the WMFT performance time score was small (SRM=0.38). The responsiveness of the FMA was significantly larger than those of the ARAT and the WMFT-TIME, but not the WMFT functional ability scores. With respect to construct validity, correlations between the FMA and other measures were relatively high (&rgr;=0.42–0.76). The FMA and the WMFT performance time scores at pretreatment had moderate predictive validity with the FIM scores at posttreatment (&rgr;=0.42–0.47). In addition, the ARAT and the WMFT functional ability scores revealed a low predictive validity with the FIM (&rgr;=0.17–0.26). Conclusions— The results support the FMA and the WMFT-FAS are suitable to detect changes over time for patients after stroke rehabilitation. While simultaneously considering the responsiveness and validity attributes, the FMA may be a relatively sound measure of motor function for stroke patients based on our results. Further research based on a larger sample is needed to replicate the findings.

Effects of Constraint-Induced Therapy Versus Bilateral Arm Training on Motor Performance, Daily Functions, and Quality of Life in Stroke Survivors

Background and Objective. This study investigated the relative effects of distributed constraint-induced therapy (CIT) and bilateral arm training (BAT) on motor performance, daily function, functional use of the affected arm, and quality of life in patients with hemiparetic stroke. Methods. A total of 60 patients were randomized to distributed CIT, BAT, or a control intervention of less specific but active therapy. Each group received intensive training for 2 hours/day, 5 days/week, for 3 weeks. Pretreatment and posttreatment measures included the Fugl—Meyer Assessment (FMA), Functional Independence Measure (FIM), Motor Activity Log (MAL), and Stroke Impact Scale (SIS). The proximal and distal scores of FMA were used to examine separate upper limb (UL) elements of movement. Results . The distributed CIT and BAT groups showed better performance in the overall and the distal part score of the FMA than the control group. The BAT group exhibited greater gains in the proximal part score of the FMA than the distributed CIT and control groups. Enhanced performance was found for the distributed CIT group in the MAL, the subtest of locomotion in the FIM, and certain domains of the SIS (eg, ADL/IADL). Conclusion. BAT may uniquely improve proximal UL motor impairment. In contrast, distributed CIT may produce greater functional gains for the affected UL in subjects with mild to moderate chronic hemiparesis.

Effects of modified constraint-induced movement therapy on reach-to-grasp movements and functional performance after chronic stroke: a randomized controlled study

Objective: To evaluate changes in (1) motor control characteristics of the hemiparetic hand during the performance of a functional reach-to-grasp task and (2) functional performance of daily activities in patients with stroke treated with modified constraint-induced movement therapy. Design: Two-group randomized controlled trial with pretreatment and posttreatment measures. Setting: Rehabilitation clinics. Subjects: Thirty-two chronic stroke patients (21 men, 11 women; mean age=57.9 years, range=43—81 years) 13—26 months (mean 16.3 months) after onset of a first-ever cerebrovascular accident. Intervention: Thirty-two patients were randomized to receive modified constraint-induced movement therapy (restraint of the unaffected limb combined with intensive training of the affected limb) or traditional rehabilitation for three weeks. Main measures: Kinematic analysis was used to assess motor control characteristics as patients reached to grasp a beverage can. Functional outcomes were evaluated using the Motor Activity Log and Functional Independence Measure. Results: There were moderate and significant effects of modified constraint-induced movement therapy on some aspects of motor control of reach-to-grasp and on functional ability. The modified constraint-induced movement therapy group preplanned reaching and grasping (P=0.018) more efficiently and depended more on the feedforward control of reaching (P=0.046) than did the traditional rehabilitation group. The modified constraint-induced movement therapy group also showed significantly improved functional performance on the Motor Activity Log (P<0.0001) and the Functional Independence Measure (P=0.016). Conclusions: In addition to improving functional use of the affected arm and daily functioning, modified constraint-induced movement therapy improved motor control strategy during goal-directed reaching, a possible mechanism for the improved movement performance of stroke patients undergoing this therapy.

Randomized Trial of Distributed Constraint-Induced Therapy Versus Bilateral Arm Training for the Rehabilitation of Upper-Limb Motor Control and Function After Stroke

Background and Objective. This study compared the efficacy of distributed constraint-induced therapy (dCIT), bilateral arm training (BAT), and control treatment (CT) on motor control and functional performance of the upper limb in stroke patients. Methods. A total of 66 patients with mean stroke onset of 16.20 months and mild to moderate motor impairment were randomized to dCIT, BAT, or CT groups. Each group received treatment for 2 h/d and 5 d/wk for 3 weeks. Pretreatment and posttreatment measures included reaching kinematic variables in unilateral and bilateral tasks, the Wolf Motor Function Test (WMFT), and the Motor Activity Log (MAL). Results. The dCIT and BAT groups had smoother reaching trajectories in the unilateral and bilateral tasks than the CT group. The BAT group, but not the dCIT group, generated greater force at movement initiation than the CT group during the unilateral and bilateral tasks. The dCIT patients had decreased WMFT time and higher functional ability scores than the CT patients. MAL results pointed to better performance in the amount and quality of use of the affected arm than BAT and CT patients. Conclusions. BAT and dCIT exhibited similar beneficial effects on movement smoothness but differential effects on force at movement initiation and functional performance. Therefore, BAT is a better option if improvement of force generation is the treatment goal, and dCIT is more appropriate for improving functional ability and use of the affected arm in daily life. These findings may assist in the planning of individually tailored rehabilitation therapies.

Constraint-induced therapy versus dose-matched control intervention to improve motor ability, basic/extended daily functions, and quality of life in stroke.

Background. Trials of constraint-induced movement therapy (CIT) to improve upper extremity function after stroke have usually not included an actively treated control group. Objective. This study compared a modified CIT intervention with a dose-matched control intervention that included restraint of the less affected hand and assessed for differences in motor and functional performance and health-related quality of life. Methods. This 2-group randomized controlled trial, using pretreatment and posttreatment measures, enrolled 32 patients within 6 to 40 months after onset of a first stroke (mean age, 55.7 years). They received either CIT (restraint of the less affected limb combined with intensive training of the affected limb for 2 hours daily 5 days per week for 3 weeks and restraint of the less affected hand for 5 hours outside of the rehabilitation training) or a conventional intervention with hand restraint for the same duration. Outcome measures were the Fugl-Meyer Assessment, Functional Independence Measure, Motor Activity Log, Nottingham Extended Activities of Daily Living Scale, and Stroke Impact Scale. Results. Compared with the control group, the CIT group exhibited significantly better performance in motor function, level of functional independence, mobility of extended activities during daily life, and health-related quality of life after treatment. Conclusions. The robust effects of this form of CIT were demonstrated in various aspects of outcome, including motor function, basic and extended functional ability, and quality of life.

Effects of robot-assisted upper limb rehabilitation on daily function and real-world arm activity in patients with chronic stroke: a randomized controlled trial

Objective: To compare the outcome of robot-assisted therapy with dose-matched active control therapy by using accelerometers to study functional recovery in chronic stroke patients. Design: Prospective, randomized, controlled trial. Setting: Stroke units in three medical centres. Subjects: Twenty patients post stroke for a mean of 22 months. Intervention: Robot-assisted therapy (n = 10) or dose-matched active control therapy (n = 10). All patients received either of these two therapies for 90–105 minutes each day, 5 days per week, for four weeks. Main measures: Outcome measures included arm activity ratio (the ratio of mean activity between the impaired and unimpaired arm) and scores on the Fugl-Meyer Assessment Scale, Functional Independence Measure, Motor Activity Log and ABILHAND questionnaire. Results: The robot-assisted therapy group significantly increased motor function, hemiplegic arm activity and bilateral arm coordination (Fugl-Meyer Assessment Scale: 51.20 ± 8.82, P = 0.002; mean arm activity ratio: 0.76 ± 0.10, P = 0.026; ABILHAND questionnaire: 1.24 ± 0.28, P = 0.043) compared with the dose-matched active control group (Fugl-Meyer Assessment Scale: 40.90 ± 13.14; mean arm movement ratio: 0.69 ± 0.11; ABILHAND questionnaire: 0.95 ± 0.43). Conclusions: Symmetrical and bilateral robotic practice, combined with functional task training, can significantly improve motor function, arm activity, and self-perceived bilateral arm ability in patients late after stroke.

Minimal detectable change and clinically important difference of the Stroke Impact Scale in stroke patients.

Objectives. The purpose of this study was to establish the minimal detectable change (MDC) and clinically important differences (CIDs) of the physical domains of the Stroke Impact Scale (SIS) and to assess the proportions of patients’ change scores exceeding the MDC and CIDs after stroke rehabilitation. Methods. Seventy-four patients received 1 of 3 treatments for 3 weeks and underwent clinical assessment before and after treatment. The MDC was calculated from the standard error of measurement to indicate a real change with 95% confidence for individual patients (MDC95). Anchor-based and distribution-based approaches were adopted to triangulate the ranges of minimal CIDs. The percentage of patients exceeding MDC95 and minimal CIDs were also calculated. Results. The MDC95 of the strength, activities of daily living/instrumental activities of daily living, mobility, and hand function subscales were 24.0, 17.3, 15.1, and 25.9, respectively. The respective minimal CIDs for these 4 subscales were 9.2, 5.9, 4.5, and 17.8 points, respectively, and the MDC95 and CID proportions were 14% to 43%, 16% to 49%, 10% to 50%, and 23% to 64%, respectively. Conclusions . The change score of an individual patient has to reach 24.0, 17.3, 15.1, and 25.9 on the 4 subscales to indicate a true change. The mean change scores of a stroke group on the 4 subscales should reach 9.2, 5.9, 4.5, and 17.8 points to be regarded as clinically important changes. Future research with larger sample sizes is warranted to validate these estimates.

Effects of Modified Constraint-Induced Movement Therapy on Movement Kinematics and Daily Function in Patients With Stroke: A Kinematic Study of Motor Control Mechanisms

Background and Objective. Motor control of the upper extremity during unilateral and bimanual functional tasks and functional change during daily activities were evaluated in patients with stroke treated with modified constraint-induced movement therapy (mCIMT). Methods. In a pre-post randomized, controlled trial, 30 stroke patients received 2 hours of mCIMT or traditional rehabilitation (TR) for 3 weeks. Motor control of the upper extremity was evaluated using kinematic analysis in unilateral and bilateral tasks. Kinematic variables included spatial and temporal movement efficiency and type of movement control (preplanned control, representing well-learned movement, or feedback-guided control). Functional outcomes were evaluated using the Motor Activity Log (MAL) and the Functional Independence Measure (FIM). Results. Patients receiving mCIMT showed more temporally (P = .013) and spatially (P = .011) efficient movement and more preplanned movement control (P = .009) during the bimanual task, and greater gains in FIM (P = .004) and MAL scores (amount of use: P < .0001, and quality of movement: P = .012) than patients in the TR group. Patients receiving mCIMT produced more ballistic/preplanned reaching movement than did patients receiving TR (P = .023) during the unilateral task; but there were no group differences in temporal or spatial efficiency in unilateral task performance. Conclusions. Relative to TR, mCIMT produced a greater improvement in functional performance and motor control. Improvement of motor control after mCIMT was based on improved spatial and temporal efficiency, apparently more salient during bimanual rather than unilateral task performance. This suggests that bilateral task performance should potentially be emphasized in kinematic study of changes in motor control after mCIMT.

The Effects of Bilateral Arm Training on Motor Control and Functional Performance in Chronic Stroke: A Randomized Controlled Study

Background. Most studies of bilateral arm training (BAT) did not employ a randomized controlled trial design and involved very limited functional training tasks. Objective . Compare the effects of BAT with control intervention (CI) on motor control and motor performance of the upper extremity and also functional gains in patients with chronic stroke. Methods. This 2-group randomized controlled trial with pretreatment and posttreatment measures enrolled 33 stroke patients (mean age = 53.85 years) 6 to 67 months after onset of a first stroke. They received either a BAT program concentrating on both upper extremities moving simultaneously in functional tasks by symmetric patterns or CI (control treatment) for 2 hours on weekdays for 3 weeks. Outcome measures included kinematic analyses assessing motor control strategies for unilateral and bimanual reaching and clinical measures involving the Fugl-Meyer Assessment (FMA) of motor-impairment severity and the Functional Independence Measure (FIM) and the Motor Activity Log (MAL) evaluating functional ability. Results. After treatment, the BAT group showed better temporal and spatial efficiency during unilateral and bilateral tasks and less online error correction only during the bilateral task than the control group. The BAT group showed a significantly greater improvement in the FMA than the control group but not in the FIM and MAL. Conclusions. Relative to CI, BAT improved the spatiotemporal control of the affected arm in both bilateral and unilateral tasks, decreased online corrections to perform bilateral tasks, and reduced motor impairment. These findings support the use of BAT to improve motor control and motor function of the affected upper limb in stroke patients.