Orthotics are supports applied over a specific joint (e.g., ankle or wrist) while the joint is held in a functional position. Casting and orthotics are designed to work along with therapy and are used for both the upper and lower extremities. They are commonly used for children with cerebral palsy in the belief that they can prevent or reverse contractures and deformity, decrease spasticity, relieve pain, or improve balance and function. Often, because of the high cost of orthotics and the fact that children grow quickly, clinicians use splinting and casting materials instead of orthotics or as a precursor to them. There are several names for similar devices (splints, bivalved or circular inhibitive casts, tone reducing ankle foot orthoses (TRAFOs) and hinged or fixed ankle foot orthoses (AFOs)).

Two rationales for casting\orthotics have been proposed: the biomechanical rationale stresses the need to position joints to prevent contractures, whereas the neurophysiological rationale emphasizes that prolonged lengthening of the muscle decreases spasticity and abnormal reflexes.

Results from the previous studies performed on the effectiveness of casts have concluded that lower extremity "inhibitive casting" results in increased stride length during walking and increased range of motion of the ankle. Upper extremity casting results in increased range of motion at the wrist, and increased quality of upper extremity movement. Children from 4-8 years improved more than younger children in quality of movement.