Patients struggling with foot, ankle, or gait issues can see tremendous benefits from ankle-foot orthosis. In addition, orthosis worn regularly may allow patients to permanently remedy ongoing issues or prolong the ability to walk for patients who suffer from degenerative disease.
However, to truly understand the benefits of an ankle-foot orthosis (AFO), you need to understand AFOs themselves.
What Is Ankle-Foot Orthosis?
An ankle-foot orthosis is a mechanical medical device that attaches to the leg and foot to control the ankle’s position and motion, compensate for weakness, or correct deformities.
Each ankle-foot orthosis serves two main functions. First, it acts as a supportive device for walking through different gait stages. In this capacity, the ankle-foot orthosis supports the ankle and foot through several functions, including:
Providing foot clearance
Limiting or assisting ankle and foot range of motion
Decreasing the risk of falling
Strengthening leg muscles
The support of the orthotic in walking makes it the most common treatment for foot drop. Ankle foot orthosis for foot drop keeps the toes from dragging while walking. A variety of neurological or musculoskeletal disorders may cause foot drop.
Patients may also use AFO braces as night splints to prevent contractures. In this capacity, AFOs support patients recovering from surgery or trauma and may help those with inherited disorders or underlying conditions maintain their walking ability.
Types of AFOs
The type of ankle-foot orthosis brace that works for you depends on your individual needs. While your physician will recommend the best option for your body and condition, understanding the ankle-foot orthosis types ensures you’ll end up with the right AFO for your needs.
Articulated AFOs offer a hinge at the ankle and plantar flexion stop. The adjustable hinge allows for controlled movement, and physicians can alter them based on your needs. Patients must wear articulated AFOs with a structured shoe to ensure stability.
Articulated AFOs are best for treating stress fractures, medial/lateral instability, and CVA. However, patients with diabetes or fluctuating fluid and swelling of the feet should not use an articulated AFO.
Carbon Fiber AFO
Traditional AFOs use a plastic design, but carbon-fiber AFOs bring a more lightweight composition to AFO orthotics. Carbon-fiber AFOs usually feature a flat footplate attached to a full-length orthotic.
Praised for being slightly flexible and storing energy from movement, carbon-fiber AFOs create a spring-like action, adding ease to forward motion. Patients with foot drop find this feature especially beneficial. Additionally, some patients even gain muscle mass in their calves from the improved function of carbon-fiber AFOs.
While carbon-fiber AFOs treat many conditions, they’re best for patients with:
Minor coronal plane deformity in the ankle
Minimal fluctuating edema (swelling)
Low to no spasticity
Minimal equinus contracture
Carbon-fiber AFOs treat injuries and genetic diseases and aid in post-surgical and illness recovery.
A dynamic ankle-foot orthosis (DAFO) uses thin thermoplastic to provide a custom fit to the patient’s foot. Unlike many foot ankle orthotics, the plastic used in DAFO is more flexible, allowing the patient’s alignment to remain neutral and providing circumferential control of the foot.
Since DAFOs are less stringent than other AFOs, they’re best used where deformities require minimal force to correct.
Ground Reaction AFO
Ground reaction or floor reaction AFO are molded ankle-foot orthoses that are custom created. This orthotics offer more leverage than similar designs by redistributing the extension and ground reaction forces closer to the knee.
The use of Ground reaction AFOs significantly benefits patients with brain or spinal cord injuries, spina bifida, cerebral palsy, PTTD, and adult acquired flatfoot.
Posterior Leaf Spring AFO
The posterior leaf spring AFO is flexible at the ankle so that patients receive a smoother knee to ankle motion when walking. Less rigid than other orthotics, this ankle-foot orthosis brace mainly supports the foot as its swings to clear the ground.
Like the carbon-fiber AFO, the footplate of the posterior leaf spring AFO stores energy, providing a small spring that helps propel patients forward. Carbon composites, copolymer polypropylene, or Ortholen form the main composition of posterior leaf spring AFOs. They primarily treat patients with mild spastic equinus.
Rigid or solid AFOs are the most structured AFO and provide full coverage along the back of the leg, allowing for no movement. In addition, rigid AFOs allow for toe clearance as the foot swings and offer complete stability for the entire foot and ankle.
Rigid AFOs are often used to treat children with cerebral palsy, both ambulatory and non-ambulatory.
How Does Foot Orthosis Work?
Foot orthoses are shoe inserts specifically designed to help support the feet and improve foot posture. In addition, the orthotics put the foot into a better position to alleviate pain. If a muscle is strained or hurting, then the right orthotic will reduce the muscle’s workload and provide relief.
Most foot orthoses benefit patients with chronic foot or leg problems that keep their feet from functioning correctly. For example, a podiatrist may prescribe foot orthosis to a patient with persistent calluses to redistribute their body weight across their feet or to an athlete whose foot issues hinder their performance.
What Is the Correct Way to Wear Your AFO?
Correctly wearing your foot and ankle orthosis ensures you won’t struggle with blisters and rubbing, making the orthotic uncomfortable. For the best fit in your AFO, follow these simple rules:
Wear a Long Sock
All AFOs need a smooth, long sock underneath to be a barrier between the AFO and the skin. The sock reduces the chances of skin problems and prevents plastic orthotics from sticking to the skin.
Use a Structured Shoe
AFOs require a lace-up or velcro shoe that adjusts to the added space that the AFO needs around the foot. In addition, any shoe worn with an AFO needs to have a solid heel and adjustable forefoot section. Discuss your footwear choices with your orthotist to be confident in your selection.
Allow an Adjustment Period
Your foot, ankle, and skin may need time to adjust to wearing an AFO regularly. Therefore, gradually increase your time in your orthosis so your body can acclimate to the new device.
Consistently Look for Potential Problems
Check your skin for redness, blisters, or sores before and after your AFO fitting. While you can expect some redness with a new orthotic, the redness should dissipate as your skin grows accustomed to the device. However, if redness persists or blisters and sores develop, contact your orthotist to review your fit.
Additionally, check the parts of ankle-foot orthosis devices to ensure they are in good condition and haven’t developed any rough edges or areas where they can irritate the skin.
Adjust the AFO with Growth
As your body changes, AFOs may need to be adjusted or replaced. Monitor the fit of your AFO. If anything changes in your body to cause the AFO to fit incorrectly, contact your orthotist. A poor fit can adversely affect the muscles and foot structure.
Problems Associated with AFO Orthotics
The most common problems associated with ankle-foot orthoses form in the skin. Ill-fitting AFOs may cause skin redness, blisters, and sores. Patients suffering from skin irritation from wearing their orthotics can try these troubleshooting methods:
Check the application of the AFO
Check the fit of the AFO, including where the heel sits
Firmly secure the ankle and shoe straps
Assess for changes in the body that cause the AFO to fit improperly
Change socks, as some socks can vary the pressure or friction of the brace
Ensure the skin is clean and dry before attaching the AFO
If you experience a skin breakdown where the AFO attaches, stop using the orthotic and schedule a review appointment with your orthotist.
How to Care for Ankle Foot Orthotics
Since you’ll wear your ankle-foot orthosis for long periods, it can become dirty quickly. To keep it clean, regularly wipe it down with a damp cloth and soapy water. Make sure your AFO is completely dry before putting it back on.
You can make a solution of one tablespoon of unscented bleach in a gallon of warm water to clean your orthosis and can keep velcro straps clean using a wire brush, toothbrush, or fine-toothed comb to brush out any lint or hair buildup. You may need to lightly lubricate metal joints occasionally with silicone spray or light oil like WD40.
To maintain the integrity of your orthotic, avoid wetting the velcro or straps. If they happen to get wet, try to dry them as best as possible with a towel. Never use a heat source, like a hairdryer, to dry your AFO. Don’t leave your AFO in a hot car.