Current Insights On Prescribing AFOs

Our expert panelists discuss the use of hinged and non-hinged ankle foot orthoses (AFOs), and offer pearls from their experience for ensuring shoe fit when patients begin wearing AFOs.  

Q:

What types of hinged AFOs do you most frequently prescribe and for which conditions?

A:

The most common condition for which Doug Richie, Jr., DPM, prescribes any AFO is adult-acquired flatfoot. For stage 1, 2 and 3 adult-acquired flatfoot, he favors using articulated AFOs with free motion in the ankle joints. He says the Standard Richie Brace addresses this requirement.

Patrick DeHeer, DPM, uses the Richie Brace almost exclusively as his hinged AFO of choice. He uses the brace for a variety of conditions, including stage 2 tibialis posterior tendon dysfunction that does not respond to an orthosis; ankle instability; weakness due to prior injury or neuromuscular disease; and arthrosis of the ankle, hindfoot or midfoot.

As a pediatric specialist, Russell Volpe, DPM, uses mostly hinged AFOs with plantarflexion stop. He primarily uses them for toe walkers for whom he wants to allow dorsiflexion but limit plantarflexion contributing to toe-walking. Dr. Volpe may also use hinged AFOs in patients with hyper- or hypotonic cerebral palsy who have a need for control of a valgus foot deformity and some control of the leg segment. If the patient has ankle dorsiflexion to tap into, he favors a hinged design to allow the leg to move over the foot during stance. Dr. Volpe may also use a hinged AFO after tendon lengthening to allow the child to use newly increased ankle dorsiflexion (through the hinge) while still offering all the stabilizing/controlling benefits of an AFO.

The second most common condition for which Dr. Richie prescribes an AFO is dropfoot. He notes the Dynamic Assist Richie Brace with Tamarack flexure ankle joints “addresses this condition beautifully” by providing dorsiflexion assist during swing and unrestricted plantarflexion during the stance phase of gait. Dr. Richie says these are the two most commonly prescribed hinged AFOs. For dropfoot, Dr. DeHeer uses a Richie Brace, taking advantage of its spring mechanism.

Q:

What types of non-hinged AFOs do you most frequently prescribe and for which conditions?

A:

For non-hinged AFOs, Dr. Volpe uses a variation on a posterior leaf spring AFO with carbon fiber reinforcement of the posterior plastic for strength. He says this allows some dorsiflexion for gait as it tends to be less restrictive than a traditional solid AFO. Dr. Volpe will make the device with a neutral ankle at 90 degrees and cast in subtalar neutral with a ¾ length foot plate to enhance dorsiflexion. In cases of hypotonicity or severe spasticity, Dr. Volpe may use a traditional solid AFO for more control.

Dr. Richie uses non-hinged AFOs for stage 4 adult-acquired flatfoot and degenerative arthritis of the ankle or hindfoot. He feels the Restricted Hinge Richie Brace works very well for these conditions. Dr. Richie notes the device is not overly rigid and allows a smooth contact phase of the gait cycle in comparison to more rigid solid AFOs. In patients who require total restriction of motion, such as severe deformity or degenerative joint disease, he will use a gauntlet AFO. “There can be problems with shoe fit and balance when patients wear such a restrictive device,” he cautions.

Dr. Richie also uses a traditional solid AFO for spastic conditions such as cerebral palsy. He also uses a solid AFO when controlling tibial progression for patients with an unstable knee from quadriceps weakness or soleus weakness.

Dr. Volpe also uses supramalleolar orthoses for many patients who do not require a full AFO. He notes these patients are typically severe foot and ankle pronators, usually with high laxity and/or low-tone who require correction above the malleolar to stabilize the foot and ankle. He says the trim line on these is usually low enough to still allow enough ankle dorsiflexion in gait.

Dr. DeHeer will use either a locked-hinge Richie Brace or an Arizona type of brace for a non-hinged brace, making the determination by considering foot architecture. He will use an Arizona Brace for a patient with a deformed, rigid foot, such as a patient with Charcot, stage 3 or 4 posterior tibial tendon dysfunction or Charcot-Marie-Tooth disease. If there is reducibility of the deformity, he prefers the Richie Brace with a locked hinge.

Q:

What shoe modifications do you most frequently prescribe for use with an AFO?

A:

Dr. DeHeer does not use many shoe modifications for AFOs other than an extra-depth type of shoe to accommodate for the bulk of the brace. He always has the patient wait to purchase a shoe until receiving the AFO to try shoes on with the brace to ensure fit.

The shoe has to fit and work with the AFO, according to Dr. Volpe, who likewise encourages patients/parents to wait until they have the AFO/supramalleolar orthosis to buy the shoe as the device often dictates a change in size or style. He encourages a wider midsole if stability is an issue. As Dr. Volpe notes, a ¾ height or high top shoe often works well with a supramalleolar orthosis design as it offers more shoe to hold the device. He says a low-top shoe is sometimes too shallow to accommodate the room required for the AFO/supramalleolar device.

Dr. Richie’s most common shoe modification is an outsole flare, particularly a lateral flare for severe varus deformity of the ankle or hindfoot. He will occasionally prescribe a heel rocker for patients using a solid AFO to protect the knee and slow down tibial progression during the contact phase of gait.  

Dr. DeHeer is a Fellow of the American College of Foot and Ankle Surgeons, and a Diplomate of the American Board of Podiatric Surgery. He is also a team podiatrist for the Indiana Pacers and the Indiana Fever. Dr. DeHeer is in private practice with various offices in Indianapolis. Dr. DeHeer writes a monthly blog for Podiatry Today. One can access his blog at https://www.podiatrytoday.com/blog/289 .

Dr. Richie is an Adjunct Associate Professor within the Department of Applied Biomechanics at the California School of Podiatric Medicine at Samuel Merritt University in Oakland, Calif. He is a Fellow and Past President of the American Academy of Podiatric Sports Medicine. Dr. Richie is a Fellow of the American College of Foot and Ankle Surgeons. He is in private practice in Seal Beach, Calif., and is the inventor of the Richie Brace. Dr. Richie writes a monthly blog for Podiatry Today. One can access his blog at www.podiatrytoday.com/blogs/301 .

Dr. Volpe is a Professor in the Department of Orthopedics and Pediatrics at the New York College of Podiatric Medicine in New York City. He is in private practice in New York City and Farmingdale, N.Y.