Immediate effects of standing unstable board intervention on the non-paralyzed leg on sitting balance in severe hemiplegia: a randomized controlled trial.

The standing unstable board intervention for the non-paralyzed lower limb increased sensory input to the non-paralyzed side of the trunk weight-bearing on the lower limb of the paralyzed side. The increase in the righting reaction angle and the movement distance of the center of pressure contributed to improved sitting balance.