Functional Prognosis Post Stroke---A Longitudinal Study

The specific aims of this project are three-fold: (1) to determine the recovery course and factors influencing outcome in stroke patients on clinical measures at the body, person, and social levels; (2) to study the recovery course of affected and "unaffected" sides of stroke patients using biomechanical measures; and (3) to examine the impact of environmental factors on upper extremity or postural balance during the recovery course. The recovery course (1)The body level: (a) Motor performance: The greatest improvements on the scores of the F-M scale occurred from 1 to 6 months since onset. The recovery seemed stationary from 2 to 3 years except for comorbidity. The course of stroke recovery was, however, influenced by neurological severity and intervals and types of rehabilitation programs. (b) Perceptual performance: Patients with only stimuli centered neglect (SCN) recovered better than those with body centered neglect (BCN) or both SCN + BCN at 6 months.(2) The person level: The recovery of function of activities of daily living (ADL) occurred primarily between 6 -36 months. Those who received rehabilitation more than 6 months showed better recovery of ADL than those less than 6 months. A better recovery course was found in patients with only SCN than with only BCN and with both SCN and BCN.(3) The social level: The total scores of SIS significantly increased at 2 and 3 years than at 1 year. Those patients receiving CIMT showed higher scores than those receiving regular rehabilitation programs. The recovery course of affected and "unaffected" sides of stroke patients: kinematic analyses For those who could perform the tasks using the affected arm, the normalized movement time decreased and peak velocity increased significantly at 2 years than at 1 year. Compared to normal adults, the movement time (MT) and peak velocity (PV) of the unaffected arm were less in stroke patients. The impact of environmental factors (1) The effects of instruction and target location on the unaffected arm: The LCVA group demonstrated significant and large effects of task instructions and target locations on reaction time (RT), MT, PV, and movement units (MU), and the RCVA group on MT, PV, and MU. Both groups showed more efficient and smoother movements with greater force generation (for speed- vs. accuracy-emphasized conditions, and for ipsilateral vs. contralateral conditions. These findings suggested motor rehabilitation may incorporate constraint parameters into practice in consideration of task context and lesion laterality.(2) The influence of object presence/absence on reaching and postural control: The concrete task induced farther reaching distance and more lateral shift of CoP than the abstract task in the control group. The RCVA group showed farther reaching distance, less lateral shift of CoP and tended to bear more weight on the affected leg in the concrete task than the abstract task. The findings suggested that such a task might restore patient's postural control in terms of CoP and weight distribution.(3) The impact of target distance and trunk constraint on upper extremity and trunk control: As the target distanced increased, PV, PPV, and angular change of both joints increased. The angular change of elbow was largest at the critical distance. As the target distance was greater than the critical distance, the angular change of shoulder flexion played a more important role than that of elbow. The effects of trunk restraint occurred in the variables of angular changes. The findings suggested therapists modulate target distance and trunk restraint to improve the movement efficiency or range of motion of upper extremity in stroke patients.

Project ID:PG9403-1062
External Project ID:NHRI-EX94-9103EC