Background. Total reaching range of motion (work area) diminishes as a function of shoulder abduction loading in the paretic arm in individuals with chronic hemiparetic stroke. This occurs when reaching outward against gravity or during transport of an object. Objectives. This study implements 2 closely related impairment-based interventions to identify the effect of a subcomponent of reaching exercise thought to be a crucial element in arm rehabilitation. Methods. A total of 14 individuals with chronic moderate to severe hemiparesis participated in the participant-blinded, randomized controlled study. The experimental group progressively trained for 8 weeks to actively support the weight of the arm, up to and beyond, while reaching to various outward targets. The control group practiced the same reaching tasks with matched frequency and duration with the weight of the arm supported. Work area and isometric strength were measured before and after the intervention. Results. Change scores for work area at 9 loads were calculated for each group. Change scores were significantly larger for the experimental group indicating a larger increase in work area, especially shoulder abduction loads equivalent to those experienced during object transport. Changes in strength were not found within or between groups. Conclusions. Progressive shoulder abduction loading can be utilized to ameliorate reaching range of motion against gravity. Future work should investigate the dosage response of this intervention, as well as test whether shoulder abduction loading can augment other therapeutic techniques such as goal-directed functional task practice and behavioral shaping to enhance real-world arm function.

Background. Kinematic and kinetic measurements used in laboratory settings can quantify upper extremity movement impairment following stroke, but their relationship to clinical methods of evaluating movement impairment is unclear. Objective. To test whether the Arm Coordination Training 3D device (ACT^3D) could provide a repeatable quantitative measurement of range of motion during upper extremity reaching along a range of functional levels of loads on the arm and correlate with clinical assessments of arm impairment. Methods . Work area during reaching along clockwise and counterclockwise hand paths was measured under 9 limb-loading conditions ranging from no load to twice the weight of the upper extremity in 11 individuals with chronic hemiparetic stroke on 2 separate occasions. Participants were given a battery of clinical assessments that included the Fugl-Meyer Motor Assessment, Chedoke McMaster Stroke Assessment, Reaching Performance Scale, Modified Ashworth Scale, and the Stroke Impact Scale, by a physical therapist who did not know the results of the kinematic studies. Results. A reproducible testretest reduction in work area was found when participants were required to support up to and beyond the weight of their limb. Work area was correlated with most upper extremity clinical assessments, suggesting criterion validity. Conclusions . Reaching work area during various loading conditions is a robust measurement that quantifies the effect of abnormal joint torque coupling and provides useful data that can be applied in the clinical setting.

The implementation of a robotic system ( ACT ^3D ) that allowed for a quantitative measurement of abnormal joint torque coupling in chronic stroke survivors and, most importantly, a quantitative means of initiating and progressing an impairment-based intervention, is described. Individuals with chronic moderate to severe stroke ( n = 8) participated in this single-group pretest-posttest design study. Subjects were trained over eight weeks by progressively increasing the level of shoulder abduction loading experienced by the participant during reaching repetitions as performance improved. Reaching work area was evaluated pre- and postintervention for ten different shoulder abduction loading levels along with isometric single-joint strength and a qualitative clinical assessment of impairment. There was a significant effect of session (pre versus post) with an increase in reaching work area, despite no change in single-joint strength. This data suggests that specifically targeting the abnormal joint torque coupling impairment through progressive shoulder abduction loading is an effective strategy for improving reaching work area following hemiparetic stroke. Application of robotics, namely, the ACT ^3D , allowed for quantitative control of the exercise parameters needed to directly target the synergistic coupling impairment. The targeted reduction of abnormal joint torque coupling is likely the key factor explaining the improvements in reaching range of motion achieved with this intervention.

Aim: This study examined the reliability and validity of the Test of Arm Selective Control (TASC) to examine upper extremity selective voluntary motor control in children and adolescents with all types of spastic cerebral palsy (CP).Method: Fifty‐six participants with CP, ranging in age from 5 years 9 months to 18 years 11 months (average 11y 7mo, SD 3y 9mo; 25 males, 31 females), participated in this prospective cross‐sectional study. They were evaluated using the TASC and several clinical measures.Results: TASC and Manual Ability Classification System (r=−0.529, p<0.001), TASC and ABILHAND‐Kids (r=0.596, p<0.001), and TASC and affected extremities (r=−0.486, p=0.001) were moderately correlated. There was a weak correlation between the TASC and Gross Motor Function Classification System (r=−0.363, p=0.006) and no correlation between the TASC and age (p=0.366) or rater (p=0.713). Interrater reliability for upper extremity total score (intraclass correlation coefficient [ICC]=0.92–0.94) and upper extremity limb scores (ICC=0.92–0.96) was high for two independent rater groups (p≤0.001). Average time to administer was 16 minutes, 18 seconds.Interpretation: The TASC is a reliable and valid tool for objective assessment of selective voluntary motor control. Clinically this measure may guide the selection of medical, surgical, or therapy interventions and may improve outcome prognosis.What this paper adds: The Test of Arm Selective Control (TASC) demonstrates a high degree of reliability and multiple aspects of validity when assessing upper extremity selective control in those with cerebral palsy. The TASC is an upper limb companion to the Selective Control Assessment of the Lower Extremity.