Relationship between arm usage and instrumental activities of daily living after unilateral stroke.

OBJECTIVE: To determine whether the preferred pattern of arm use after unilateral hemispheric damage was associated with better everyday functioning. Our previous work showed that right-handed stroke patients with right hemisphere damage (RHD) used their right, ipsilesional arm most frequently, while those with left hemisphere damage (LHD) used both arms together most frequently. This effect was explained by right-hand preference, but its relationship to functional performance is not known.
DESIGN: Observational cohort.
SETTING: Research laboratory. PARTICIPANTS: Stroke patients (n=60; 30 RHD, 30 LHD) and healthy controls (n=52).
INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The Functional Impact Assessment was used to assess performance on instrumental activities of daily living (IADLs).
RESULTS: The preferred patterns of arm use were similar to those in our previous report. However, it was the greater use of both arms together that was associated with better IADL performance in both stroke groups. Ipsilesional arm use alone was not significantly associated with IADL performance in the RHD group and was associated with poorer performance in the LHD group.
CONCLUSIONS: The modal arm use pattern did not always optimize IADL functioning. Better IADL functioning in both stroke groups was associated with the use of both arms together, which is the most common arm use pattern of healthy individuals doing these same IADLs. An important practical question that arises from these findings is whether bilateral arm rehabilitation should be emphasized, because using both arms together is the best predictor of better performance on everyday tasks.