By this is meant the ability to mix the flexion and extension components suitably In order to achieve a balance of activity which Leeds to functional use. It will be remembered that the spastic pattern of extension in the lower limb is most commonly extension, adduction and medial rotation of the hip, an extension of the knee and plantar flexion of the foot. The reversal of this is flexion, abduction and lateral rotation of the hip, flexion of the knee and dorsiflexion of the foot.
Mature movements involve a mixture of these two synergies so that the hip does not have to adduct every time it extends but can abduct if this is more appropriate. The observant therapist needs only to think of a few basic activities to appreciate that they require a mixture of flexion and extension in any one limb. The swing phase of walking requires dorsiflexion of the foot in combination with knee…
