8 Different Types of Ankle Foot Orthosis & Their Uses

Your doctor told you that you’d need an ankle-foot orthosis to walk. It’s the first time you’ve heard of such things, and a million questions flood your mind. Will it make your life complicated? Is it difficult to get used to? How do I choose the right one for me?

Although it might be difficult to adjust to these new devices at first, they will make your life easier until you recover. In this article, we’re going to tell you everything you need to know about ankle-foot orthosis braces.

AFOs

What are AFO braces?

Ankle foot orthotics (further only AFO) are a type of braces used to support your lower leg. These devices increase joint stability, counteract atrophied muscles, and promote proper gait. Your doctor might recommend using AFOs for in-born predisposition or incidents that affect the function of your ankles and feet.

Their main purpose is to improve your stability and coordination while walking. After an injury, you may be unable to lift your whole foot off the ground. Experts refer to this as a foot drop. Since the end of your foot lags behind, you’re much more likely to trip. AFOs greatly reduce this risk.

Additionally, they can improve or limit your ability to move your foot up and down or side to side. Which one is more beneficial depends on the circumstances. AFOs vary in type, and each one has its pros and cons. We’ll discuss them in greater detail later on in the article.

What are AFO braces used for?

AFO braces improve the stability of your lower leg, namely the ankle and foot. They make walking easier for patients suffering from inherent complications or recovering from an accident. Here are some of the most common reasons people might need AFO braces:

AFO on a child

Nerve Injury

Countless neural pathways connect your brain to every other organ and limb. If the nerve in your leg becomes damaged in an accident, you might lose control of your foot. Depending on the scale of the issue, an AFO can be used to help you walk during the recovery period.

Stroke

Strokes can be incredibly dangerous and unpredictable. They occur when a blood vessel in your brain becomes clogged. As a result, parts of your brain won’t receive enough oxygen. If this goes on too long, the brain tissue will start dying. Since strokes can happen virtually anywhere in the brain, it’s difficult to tell what the consequences will be. However, they can affect the lower limbs. In this case, AFOs might be necessary.

Spinal Cord Injury

The spinal cord provides a bridge between the brain and the rest of your body – all nerves sprawl from it. In the worst-case scenario, a damaged spinal cord can lead to paralysis. But sometimes, the effect can be only temporary. If it affects your feet, your doctor can prescribe you an AFO to make walking easier.

Cerebral Palsy

Cerebral palsy is a disorder that affects muscle control and coordination. Though the severity varies from one case to another, affected individuals generally have difficulty walking. An AFO brace might offset these difficulties.

Sciatica

Sciatica refers to the pain in either of the two nerves, which run from the lower back down to the bottom of each leg. In severe cases, affected individuals can experience numbness in one of the legs. Although an AFO won’t treat the underlying cause, it can be used during treatment to relieve some of the symptoms.

Poliomyelitis

Poliomyelitis, or simply Polio, is a dangerous viral disease. Left unchecked, it can lead to paralysis or weakened muscle coordination. If this happens in the area of your ankle, then you might have to rely on an AFO to walk. Fortunately, vaccines are available for this disease.

Diabetes

Unchecked diabetes can cause a series of health complications. As sugar levels rise and blood flow decreases, nerves might not receive all the nutrients they need. It can result in a foot drop if it happens in your leg. Thus, your doctor might recommend using an ankle-foot orthotic to deal with the problem.

Spinal Stenosis

Spinal stenosis occurs when the backbone becomes too narrow to accommodate the spinal cord and other peripheral nerves. It tends to develop with rising age as an accompanying symptom of arthritis. Since the bones begin to squeeze the nerves, it can result in pain and numbness anywhere in the body. Even though surgery might be necessary to fix spinal stenosis, an AFO can make the patient’s life easier in the meantime.

Muscle Dystrophy

Muscle dystrophy is an umbrella term for many diseases that affect muscle function. While each type is slightly different, the general symptoms are the same – over time, an individual’s muscles weaken or lose their function altogether. Muscle dystrophy is mostly a genetic disorder. In milder cases, using an AFO can support the weakened muscle in your foot.

AFO on small feet

Multiple Sclerosis

Multiple sclerosis is an autoimmune disease. It causes your immune system to attack the protective myelin sheath on top of the nerves. It weakens the strength of the transmitted signal. As a result, patients can experience numbness in their limbs. Braces can improve the balance of the affected leg.

Injuries

The reason to use an AFO doesn’t always have to be so sinister. Accidents happen, whether they are sprains or broken bones. You might have to wear one while your foot recovers from either one of these injuries.

Types of AFOs

Before you visit Ottobock, you should learn about various AFO models. Below are 8 different types of ankle-foot orthosis, along with their respective uses. Understanding how each type works can better prepare you for the consultation with your physician.

AliMed Swedish AFO
AliMed Swedish AFO

Articulated AFOs

This type features a hinge at the ankle. It restricts the up-and-down motion of the foot as needed. Thus, it can offset drop foot. The hinge is versatile; your doctor can alter it to suit your needs.

However, you’ll have to wear a structured shoe together with this brace. Otherwise, it won’t be stable enough.

Articulated models are great for patients who suffer from strokes or stress fractions. They focus mainly on restoring the ankle’s lateral stability. However, they’re unfit for patients with diabetes or who are prone to swollen feet.

Rigid AFOs

This type covers the entire back of the leg up to the knee. True to its name, it restricts all movement. It improves toe clearance while the foot is in mid-air. It reduces the risk of tripping. Rigid models are mostly used to aid children with cerebral palsy.

Carbon Fiber AFOs

Carbon fiber models consist of a footplate connected to an orthotic. Thanks to their flexible design, they act like springs. Whenever you step down, the recoil facilitates your next step. Thus, they are the perfect answer to drop foot. They can promote muscle gain too.

This type is suitable for patients with little to no spasticity, mild fluctuating edema, mild equinus contracture, and mild coronal plane deformity in the ankle.

Dynamic AFOs

This custom AFO brace is tailor-made for each patient. It models the leg shape well. This dynamic brace is also incredibly flexible. Therefore, it allows for circumferential movement of the foot.

However, this flexibility isn’t appropriate for every condition. This type isn’t an option if the problem requires force and stability.

Posterior Leaf Spring AFO

This brace type doesn’t prevent passive up-and-down motion of the foot. As a result, it can make walking feel more natural. Like carbon fiber braces, posterior leaf spring models also act like springs. In doing so, they further facilitate walking.

However, they are less rigid than other types. Your doctor might recommend them to treat mild spastic equinus.

Hip knee, ankle foot orthosis

It is a special type of custom AFO brace. As its name suggests, it extends to the knees and his. It’s mostly used to correct body alignment and strengthen the bones and muscles in the lower body. It can be designed to cover one or both sides.

Ground Reaction AFO

It is another type of custom AFO brace. It shifts the extension and ground reaction forces near the knee. Because of this, it provides more leverage.

Ground reaction braces are most beneficial to patients with brain or spinal cord injuries, cerebral palsy, spina bifida, and post-polio paralysis.

MAFO braces

MAFO stands for molded ankle foot orthosis. It is an umbrella term used to describe any type of orthosis that is molded according to your leg shape. These models are usually made of malleable thermoplastics.

SMO vs. AFO in orthotics

When researching various types of braces, you might also come across SMO. Are these any different from AFOs? If so, which one is better?

Well, both types improve lower leg stability. However, they are used in different scenarios.

AFOs are always taller. They can reach up to the knee. Their primary purpose is to stabilize the ankle, foot, and knee. They’re also the perfect answer to drop foot. AFOs prevent falling into abnormal walking patterns and are invaluable in managing many muscle- and nerve-related disorders.

SMO is an acronym for supra malleolar orthoses. They’re much shorter than AFOs, running only up to the ankle. Unlike AFOs, SMOs are made for children. They might be enough to improve foot and ankle stability when the symptoms are too pronounced. These braces are also great for treating pronation. Pronation happens when the feet don’t point straight. Instead, they are pointed too far inwards or outwards. SMOs adjust side-to-side movement accordingly.

What to look for

Although your doctor will tell you which type of AFO is best for you, it will be up to you to work through the details. Since you’ll be wearing your new brace quite a lot, you must feel comfortable wearing it. Here are 5 factors you should consider when choosing your brace:

Size

Your brace should naturally fit you. However, that’s not the type of size we have in mind. Each model varies in length. Certain ones run longer than others. It might impact your mobility. Different orthotics also vary in thickness. While thicker models are more durable, they’re also heavier.

Material

The material also impacts your comfort. Typically, most models are made of plastic. Lightweight yet durable, it’s the perfect brace material. However, some types can be partially made of fabric or metal. While they might be heavier, they’re also more resilient.

Shoe / No Shoe Models

Some models are thin enough to fit into shoes. Others are more robust and act as a shoe themselves.

Replaceable parts

If you have to wear the brace for a long time, you’ll need to consider maintenance too. Quality should be your primary focus. However, braces aren’t immune to the passage of time. Eventually, the many straps and clasps will weaken. For this reason, look for models whose parts are readily available on the market.

Brand

WalkOn Reaction AFO

Even though you might be tempted to buy cheap generic models, it might not be the best idea. Reputable brands offer better quality and longevity. Thus, they’re likely cheaper in the long run. Make sure you get your brace from a trustworthy brand such as Ottobock.

CPTs for Ankle Foot Orthoses

CPT, or Current Procedural Terminology, is a list of codes that describe medical and surgical procedures and services. Below are three common ones associated with ankle-foot orthosis:

L1902 CPT Code

The L1902 CPT code stands for a pre-fabricated ankle orthosis.

L4397

The L4397 CPT code refers to either static or dynamic ankle foot orthosis.

L4631

The L4631 CPT code refers to a custom-fabricated orthosis with straps.

FAQ

Why do people need ankle-foot orthotics?

People may need ankle foot orthotics for many different reasons. But ultimately, they’re designed to stabilize the foot and improve its movements. Your doctor might recommend AFOs for injuries such as sprains. However, they’re more commonly used to aid the treatment of diseases and disorders that cause foot drop. These include cerebral palsy, multiple sclerosis, sciatica, and many more.

Are AFOs permanent?

Generally speaking, AFOs aren’t permanent. They only treat the symptoms and not the cause. These devices are great for helping patients walk. But if you rely too much on them, you can make your condition worse. Wearing an AFO means you’re not using the nerves and muscles in your foot. You’ll usually need to attend physical rehabilitation to regain control of your foot. The AFO is just a temporary walking aid.

However, some conditions can affect the foot permanently. In these rare cases, you might have to use an AFO indefinitely.

Is a walking boot an AFO?

Unlike an AFO, a walking boot helps stabilize the foot after severe injuries and surgeries. Rather than facilitating movement, it restricts it. It allows broken bones to heal correctly. Walking boots are more similar to casts than AFOs. Even though they’re nowhere near as stable as casts, patients can easily remove them when needed. Thus, they can bathe the affected leg while recovering.

How long should you wear an AFO?

No one can tell you how long you should wear an AFO other than your doctor. However, you can’t just start using it for entire days immediately. Instead, you’ll have to brake in your new brace.

Generally, you wear it for only about an hour on the first day. Each day, add one more hour until you can use it comfortably as prescribed by your doctor.

Initially, the brace might feel uncomfortable. We suggest wearing thick cotton socks to lower the friction and pressure on your foot. Even so, you might notice redness and bruises on your leg in the early days. These should fade in thirty minutes and stop appearing in a few weeks. If they persist, you should contact your doctor for further advice.

Can orthotics help drop foot?

Doctors are very likely to recommend orthotics to help with your foot drop. After all, it’s their primary purpose. These braces stabilize the ankle and prevent the toes from dropping down. Walking with foot drop would otherwise be too dangerous – you’re more likely to trip.

Remember that while orthotics help drop foot, they don’t treat it. They’re just a temporary solution during your recovery.

What is the best support for drop foot?

AFOs are the best support for drop foot. Unlike walking boots and casts, they stabilize your foot without limiting your movement. They make drop foot much more manageable. Without it, affected individuals can walk abnormally to offset this issue. However, this only makes the condition worse. If you experience a drop foot, you should consult your doctor.

Conclusion

All told, ankle foot orthosis is a brace designed to improve foot stability. It can aid with symptoms such as drop foot which can accompany many disorders. During their recovery, patients might need to use these braces to walk as effortlessly as possible. Different types exist and each one specializes in a specific condition. They range from rigid to flexible. To find out which one might help you the most, consult your doctor.