Measuring Real-World Upper-Extremity Activity of Stroke Survivors in the Outpatient Setting

RESEARCH QUESTIONS:

How do individuals poststroke receiving outpatient occupational therapy (OT) services use their upper extremities (UEs) in daily life?

Do UE functional capacity and UE performance in daily life improve similarly over the course of outpatient OT?

RATIONALE: Clinicians use standardized assessments to measure change in UE functional motor capacity, assuming that as UE functional capacity improves, so does UE performance in daily life. Self-report measures are often relied on to quantify UE performance outside of the clinic, but these have an inherent bias. The use of unbiased methods to quantify UE performance in daily life is critical for effective stroke rehabilitation. Accelerometry is an unbiased, feasible measurement tool for both healthy and stroke populations to quantify UE performance in daily life.

DESIGN: Descriptive case series

PARTICIPANTS: Thirteen clients with UE paresis due to stroke, participating in outpatient OT

METHOD: UE performance was measured repeatedly over 24-hr periods with bilateral, wrist-worn accelerometers. UE functional capacity was measured with the Action Research Arm Test (ARAT). Measurements were taken at or near the start of therapy, every 10th visit or 30 days throughout the duration of services, and at discharge.

ANALYSIS: Accelerometer data were processed via custom written algorithms in MATLAB. Individual accelerometry profiles were made at each assessment. The profiles included the bilateral magnitude (intensity of movement), magnitude ratio (contribution of each UE to an activity), and use ratio (the amount of the time the paretic UE is moving relative to the nonparetic UE). Individual density plots were created using bivariate histograms to display the data over the 24-hr period. In this descriptive case series, the sequential density plots for each person, their accompanying ARAT scores, and other descriptive/demographic data were visually inspected to look for patterns of response to OT.

RESULTS: Accelerometry data indicated that most people undergoing outpatient OT had variable but limited UE performance in daily life, as expected. Different patterns in the time series of UE functional capacity and performance measurements were observed. At least 1 of the 13 cases showed the most desirable pattern in response to OT, which was increased ARAT scores and more normalized density plots and accelerometry values. Of the remaining cases, nearly half had a consistent pattern of no changes in ARAT and no changes in density plots or accelerometry values.

The final pattern was inconsistent, where ARAT scores increased but density plots and accelerometry values did not change. The only salient characteristics between cases across the three patterns were that cases that did not change on either measure had lower initial ARAT scores and were later poststroke.

DISCUSSION: There was variability in UE use in daily life poststroke, as measured by accelerometry. Over the course of outpatient OT, UE functional capacity scores were not necessarily representative of daily performance. Changes in UE functional capacity were sometimes accompanied by changes in daily performance. These data challenge the assumption that improved UE functional capacity equals improved UE performance in daily life and highlight the importance of measuring both constructs separately.

IMPACT STATEMENT: Individuals with UE paresis poststroke continue to be limited in using their paretic UE for daily activities. There is the potential for marked inconsistency between UE functional capacity and UE performance in daily life. Measurement of UE performance in daily life should be incorporated into clinical practice.