Below-knee orthosis: a wrap-around design for ankle-foot control.

Control of foot and ankle positions with orthotic appliances is generally more difficult to accomplish in children with spastic than flaccid paralytic disorders. Our new design for a custom molded plastic ankle-foot orthosis has proven superior to other designs in most applications. The appliance is vacuum molded from very thin polypropylene plastic and innerfaced with a foam material (Aliplast). The limb is enclosed completely in plastic with an anterior opening secured by several Velcro straps. Although the material is soft and pliable, the circumferential support provides remarkably rigid control of the limb. The orthosis has been successfully applied to children with polio, meningomyelocele and all forms of spastic and athetoid cerebral palsy. In addition to superior limb control, another advantage appears to be reflex inhibition of abnormal motor tone in may spastic patients. Patients have preferred this orthosis to those previously worn probably due to greater comfort. The limitation of adjustability of dorsiflexion can be compensated by heel or sole shoe lifts. Excessive heat created by the "wrap-around" design can be reduced by a thin cotton sock extended above the orthosis.