When And How To Use AFOs Effectively

Ankle-foot orthoses (AFOs) can be beneficial for a number of lower extremity conditions. These expert panelists discuss when to use a custom-hinged AFO or a custom-gauntlet AFO. They also debate whether podiatrists would benefit from utilizing pedorthists in their practice for possible assistance with AFO prescriptions.

Q:

For what conditions do you prescribe a custom-hinged AFO?

A:

For Robert D. Phillips, DPM, hinged AFOs are indicated for those conditions in which there is weakness of the pretibial muscles or the posterior muscle group. He advises setting the AFO spring to match the muscle strength so the spring adds what the muscles cannot. In order for AFOs to control only medial or lateral instability, one has to incorporate modifications for medial or lateral stabilization into the AFO or add them to the shoe.

Most commonly, Larry Huppin, DPM, will use custom-hinged AFOs for stage 2 and stage 3 posterior tibial tendon dysfunction (adult-acquired flatfoot) prior to the onset of significant degenerative joint disease of the hindfoot. He notes that ankle-foot orthoses can also be very effective for patients with midfoot osteoarthritis who do not achieve complete relief with the use of foot orthoses and rocker-soled shoes. Occasionally, Dr. Huppin will prescribe a hinged AFO for severe lateral ankle instability.

Gene Mirkin, DPM, favors a simple approach, noting that he uses custom-hinged AFOs for tendon problems in patients with hypermobility. He notes those devices work well with patients who still need some motion with functional tendons and joints. Similarly to Dr. Huppin, he will also use AFOs for posterior tibial tendon dysfunction.  

“There are a wide variety of ways of defining ‘custom AFO,’” says Dr. Phillips. “One needs to be very detailed in defining all the goals of therapy for the patient before deciding how much customization is needed.”

Q:

When do you prescribe a custom gauntlet AFO?

A:

Dr. Mirkin finds gauntlet AFOs work best on his arthritic patients and chronic tendinosis patients, in whom stability is more necessary than motion. Similarly, Dr. Phillips says he usually limits gauntlets to significant arthritic conditions involving the ankle that are combined with high pronation or supination of the rearfoot.

Once tendons become excessively scarred or are chronically torn, with or without severe degenerative joint disease, Dr. Mirkin finds it is better to restrict as much motion as possible. He says gauntlet bracing offers that restriction as the gauntlets compress the foot and ankle joints, which most patients find tolerable.

Dr. Huppin prescribes custom gauntlet AFOs in the presence of stage 4 posterior tibial tendon dysfunction when there is concomitant degenerative joint disease of the hindfoot. In addition, he finds gauntlet AFOs useful for some patients with degenerative joint disease in the ankle.

“Essentially when even minimal joint motion leads to pain, I will prescribe a gauntlet. Often the gauntlet is an alternative to joint fusion,” says Dr. Huppin.

When he wants to significantly immobilize the ankle joint and also provide a significant degree of supination or pronation torque around the rearfoot joints, Dr. Phillips will use gauntlet AFOs. He notes one can immobilize only the ankle joint with non-hinged AFOs. Many gauntlets also require external additions to help control the pronation or supination torques, advises Dr. Phillips.
 

Q:

Do you feel utilizing a pedorthist can be helpful to a podiatric practice as far as AFO prescription goes?

A:

“I think that in general, podiatrists are, or at least should be, far better educated on the use of AFOs than pedorthists whose training in most cases focuses on shoes and foot orthoses,” argues Dr. Huppin.

If a podiatrist does not feel comfortable in prescribing, casting and dispensing AFOs, then in the best interest of the patient, Dr. Huppin says that DPM should refer the patient to a podiatrist who is experienced in AFO therapy or a certified orthotist.

Dr. Mirkin notes if one is not prescribing AFOs day in and day out, the skill set may be limited. He says physicians have to know which brace works best in certain situations from diagnosis to shoe options with/for the bracing. As he warns, incorrect or inefficient prescribing of AFOs not only fails to make patients feel better, but the wrong AFOs can sometimes cause trouble or aggravate old complaints.

That said, Dr. Mirkin is “strongly in favor” of using pedorthists, who are trained to understand, prescribe and fabricate/adjust ankle-foot orthotics to dispense to patients in any podiatric practice.
“The time and trouble it saves me and the patient makes this relationship very effective for all involved in my daily practice,” says Dr. Mirkin.

However, for those podiatrists who like to cast, prescribe and adjust bracing, Dr. Mirkin says they should keep doing so.

For Dr. Phillips, the debate over podiatrists using pedorthists is not a question with a simple yes or no answer. As he notes, there are some pedorthists who have excellent knowledge and skills. They can play a valuable role in the practice while others would not, according to Dr. Phillips. “The certification alone does not make the pedorthist useful,” says Dr. Phillips.

Dr. Phillips emphasizes that if podiatrists use the skills of a pedorthist, one should not consider the CPeds as licensed individual practitioners. He adds that podiatrists who utilize pedorthists should consider that the DPM is still responsible for everything the pedorthist does.
 
Dr. Huppin is the Medical Director of ProLab Orthotics. He is in private practice in Seattle.

Dr. Mirkin is board certified in foot surgery by the American Board of Foot and Ankle Surgery, and is board certified in foot and ankle orthopedics by the American Board of Podiatric Medicine. He is a Fellow of the American College of Foot & Ankle Orthopedics and Medicine, and a Fellow of the American Society of Podiatric Surgeons. Dr. Mirkin is the President of Foot and Ankle Specialists of the Mid-Atlantic in Maryland, Washington, DC and Virginia.

Dr. Phillips is affiliated with the Orlando Veterans Affairs Medical Center in Orlando, Fla. He is a Diplomate of the American Board of Foot and Ankle Surgery, and the American Board of Podiatric Medicine. Dr. Phillips is a Professor of Podiatric Medicine with the College of Medicine at the University of Central Florida. He is also a member of the American Society of Biomechanics.

Editor’s note: For further reading, see the following DPM Blogs by Doug Richie, Jr., DPM, FACFAS: “When Do You Prescribe A Gauntlet AFO Versus A Hinged AFO?” at https://tinyurl.com/nzve5pa , “Are Gauntlets A Universal Solution For AFO Intervention?” at https://tinyurl.com/jf66vf9 or “Should Podiatric Physicians Surrender AFO Therapy To Pedorthists?” at https://tinyurl.com/ngtvczh .