Children with hand and arm weakness as a result of neurological damage are likely to develop compensatory strategies from birth. Using the weaker arm is difficult or does not result in success, whereas the stronger arm allows them to achieve tasks. The child’s development will therefore be biased towards their stronger side and the weaker side has fewer opportunities to be stimulated or involved in play or function. This behaviour is referred to as “developmental disregard”.
As a result of this compensatory behaviour the weaker arm essentially becomes disregarded and may become even weaker. Children will learn to complete functional tasks such as feeding and dressing with their stronger side predominantly. With less sensory stimulation the affected side may become hypersensitive, or the child may dislike the arm being handled. This can make therapy interventions difficult and unpleasant for the child.
By using a light weight cast on the stronger arm the child’s focus and attention is redirected to their weaker side. Sometimes changes in muscle tone or hand position can be seen almost instantaneously once the stronger side is casted. The use of a non-removable restraint allows complete focus on the weaker side without having to physically hold the child’s stronger side or constantly instruct them to use their weaker side. The child is free to play and move independently, and can begin to explore the movement available in their weaker side.