Sit-to-walk is an asymmetric task that is challenging for individuals with stroke,
and paretic limb loading at seat-off and movement fluidity may change according to
whether the non-paretic or paretic leg is used as the leading limb. This study aimed
to investigate differences in paretic limb loading and fluidity depending on whether
the non-paretic limb or paretic limb was used as the leading limb.
Thirty-eight individuals with stroke performed sit-to-walk with each leg as the leading
limb, and their movements were measured using a 3D motion analysis system. The paired
t-test or Wilcoxon signed-rank test was used to assess differences according to limb
selection in paretic limb loading ratio at seat-off and fluidity (Fluidity Index:
ratio of the lowest to peak forward velocity before first initial contact).
Twenty-two of 38 participants preferred to use the paretic limb as the leading limb.
When leading with the paretic limb, the paretic limb loading ratio was significantly
larger (p = 0.002), and the Fluidity Index was lower (p = 0.007).
Sit-to-walk with the paretic leading limb seems to be an adaptive movement because
many participants preferred leading with the paretic limb. However, selection of the
leading limb in sit-to-walk involves a biomechanical tradeoff between paretic limb
loading at seat-off and movement fluidity in individuals with stroke. Use of the paretic
leading limb requires loading capacity of this limb, and the non-paretic leading limb
must have high balance ability to merge sit-to-stand and gait initiation.