Ankle Foot Orthosis
An AFO is an orthotic device that attaches to the lower leg and foot to control the ankle joint. An AFO helps to keep the ankle in a neutral position (90 degrees to the lower leg). It is often made of molded plastic or graphite, and fit to the patient’s lower leg (Figure 1). It is often custom fit by an orthotist, although “off-the-shelf” AFOs are available. The orthotist can perform alterations, such as adding padding to certain areas or reshaping certain areas, to improve the fit of the AFO. Hinged AFOs have a hinge built into the area above the ankle to allow for upward ankle motion (dorsiflexion).
Figure 1: Plastic heat molded AFO (Basic unit)
Who may benefit from using an AFO?
Patients who have a drop foot or significant hindfoot arthritis (ankle, subtalar, and/or talonavicular joints) may benefit from using an AFO. The AFO will keep the ankle remain in a neutral position, which will allow patients with a drop foot to walk with a much more normal gait (the involved leg will not need to be lifted as high in order for the foot to “clear” the ground). The AFO also serves to significantly limit motion through the joints of the hindfoot, and this will help to limit the pain stimulus from arthritic joints in this area (less joint movement often translates to less pain when a joint has significant arthritis).
Edited September 24, 2015