Lower-limb orthoses: what they are and why
AFO, SAFO, DAFO, GRAFO: behind the acronyms are different jobs. A short guide to what each orthosis does.
An orthosis is an external device that supports, aligns or limits joint movement. In children with cerebral palsy, muscle hypotonia and spina bifida, ankle-foot orthoses (AFO) keep the foot correctly positioned in standing and walking and prevent deformities.
SAFO is rigid and fully fixes the ankle; suited to marked spasticity. DAFO is thin and dynamic, allows some movement, and corrects foot position in milder cases. HAFO is hinged and allows dorsiflexion, so the child can squat and climb stairs. GRAFO uses ground reaction to straighten the knee in crouch gait. PLS-AFO is a posterior leaf spring for weak foot-lifting muscles.
Which orthosis is needed is decided by the doctor together with the physical therapist after assessing gait, tone and range of motion. An orthosis works only alongside therapy: it holds what the child has achieved in sessions.
