Five times sit-to-stand following stroke: Relationship with strength and balance.

BACKGROUND

Rising from a chair is an important functional measure after stroke. Originally developed as a measure of lower-limb strength, the five times sit-to-stand test has shown associations with other measures of impairment, such as balance ability. We aimed to compare strength and balance in their relationship with the five times sit-to-stand test following stroke.

METHODS

Sixty-one participants following stroke were recruited from two hospitals in this cross-sectional observational study. Participants underwent assessment of the five times sit-to-stand (measured with a stopwatch), bilateral lower-limb muscle strength of seven individual muscle groups (hand-held dynamometry), and standing balance (computerised posturography). Partial correlations (controlling for body mass and height) were used to examine bivariate associations. Regression models with partial F-tests (including pertinent covariates) compared the contribution of strength (both limbs) and balance to five times sit-to-stand time.

RESULTS

The strength of the majority of lower-limb muscle groups (6/7) on the paretic side had a significant (P < 0.05) partial correlation with five times sit-to-stand time (r = -0.34 to -0.47) as did all balance measures (r = -0.27 to -0.56). In our regression models, knee extensor strength, total path length, and anteroposterior path velocity provided the largest contribution to five times sit-to-stand over covariates amongst strength and balance measures (R = 16.6 to 17.9 %). Partial F-tests revealed that both lower-limb strength and balance contribute to five times sit-to-stand time independent of each other. A regression model containing knee extensor strength and anteroposterior path velocity accounted for 25.5 % of the variance in five times sit-to-stand time over covariates.

CONCLUSIONS

The strength of the knee extensor muscle group along with measures of standing balance ability (total path length and anteroposterior path velocity) both independently contribute to five times sit-to-stand time. Further research is required to examine how other important impairments post stroke impact five times sit-to-stand performance.