The effects of constraint-induced therapy on kinematic outcomes and compensatory movement patterns: an exploratory study.

Abstract

To determine changes in kinematic variables and compensatory movement patterns of survivors of stroke completing constraint-induced therapy (CIT). Pre-post, case series. Clinical rehabilitation research laboratory. Men (n=7) and women (n=3) with unilateral stroke occurring at least 9 months prior to study entry with moderate, stable motor deficits. Participants completed 10 consecutive weekdays of CIT for 6 hours a day comprised of trainer-supervised, functionally based activities using massed practice. Kinematic measures included movement time, average velocity, trajectory stability, shoulder abduction, and segmental contribution. Functional measures included Wolf Motor Function Test (WMFT) performance time and functional ability scores and Motor Activity Log (MAL) "how-well" scores. All measures were administered before and after the 2-week CIT intervention. Movement time, average velocity, and trajectory stability significantly improved after CIT. Participants used more shoulder flexion to reach after CIT, but also demonstrated increased compensatory shoulder abduction. Functional scores also significantly improved, including WMFT performance time and functional ability and MAL scores. There was no change in trunk movement or amount of elbow extension. CIT improved motor capacities in the hemiparetic arm as reflected in the functional outcomes and in some kinematic measures. Participants' reliance on common compensatory movements was not beneficially affected by CIT. The results of this study demonstrate that while functional capacity and some movement strategies in the hemiparetic arm improve after CIT, participants may not overcome their reliance on common compensatory movement patterns. Based on these findings, this study suggests that CIT may encourage subjects to generate movement through compensatory and/or synergy-dominated movement rather than promote the normalization of motor control. This outcome highlights the need to develop CIT further as an intervention that improves functional capacity and more normative movement strategies.