General Description - AFO Drop Foot Braces PDF Print E-mail

Treating Dropfoot with Ankle-Foot Orthoses

1. What is drop foot?

Drop foot (also known as dropfoot, footdrop and foot drop) is a term that describes a disorder where a patient has a limited ability or inability to raise the foot at the ankle joint. This makes walking difficult as the toes tend to drag on the ground which leads to tripping and instability. Patients adapt to this by using their hip muscles to exaggerate lifting the foot above the ground (known as a “steppage gait”) or by swinging their leg outward so that the foot can clear the ground (known as “circumduction”)

2. Causes of Foot Drop

Foot drop is caused by weakness that occurs in specific muscles of the ankle and the foot. The affected muscles participate in the downward and upward movement of the ankle and the foot. See picture below.

Foot drop can be associated with a variety of conditions such as dorsiflexor injuries, peripheral nerve injuries, stroke, neuropathies, drug toxicities, or diabetes

 

Foot Drop Position Comparison

 

Foot Drop Position Comparison

3. Treatment

Drop foot is often treated with the use of braces. The goal of bracing is to provide patients with a more normal and comfortable gait. At the Foot and Ankle Center of Washington we treat dropfoot with several different types of braces (also known as ankle-foot orthotics or AFOs). Our choice of which brace to make depends on each patient’s individual condition. When treating drop foot, AFOs can act in several different ways to help our patients.

To understand how AFOs work, you must first understand two standard motions that occur at the ankle joint – “dorsiflexion” and “plantarflexion”. Plantarflexion is the motion the ankle joint makes when the toes point downward. Dorsiflexion is the motion the ankle joint makes when the foot points upward. This motion needs to occur when the foot comes off the ground so that the patient does not drag their toes. Patients with dropfoot usually have a partial or complete weakness of the muscles that dorsiflex the foot at the ankle joint.

Ankle Join MovementDropfoot Seattle

There are several different types of AFOs to treat drop foot in our patients. Some of them are custom and require that we make a mold of your foot, ankle and leg. Others are prefabricated. Our goal is to provide patients with a comfortable AFO that will give them the most normal gait possible.

There are five basic types of AFOs:

  • Short leg fixed AFOs
  • Dorsiflexion assist short leg AFOs
  • Solid ankle AFO (with or without posterior stop). Also available with dorsiflexion assist.
  • Full leg posterior leaf spring AFO
  • Energy return AFOs

Short Leg AFO with Fixed Hinge (doesn’t flex at ankle joint)
This type of AFO is relatively light and easy to fit into shoes. It offers excellent control of the foot and is a good choice for patients who have dropfoot and also have a very flat foot. This AFO keeps the foot at 90 degrees to the leg. It can also help control unwanted inward rotation of the foot, which can commonly accompany dropfoot in stroke patients and Charcot-Marie Tooth patients.

The disadvantage of this fixed hinge version of this brace, as prescribed for dropfoot, is the fact that it does not allow plantar flexion or dorsiflexion, so it doesn’t provide quite as natural of a gait as do some of the other braces. Also because it is rather short, it doesn’t work as well on taller people. If you are over 6’ tall, it would be wise to prescribe different brace.

 

Short Leg AFO with Fixed Hinge

 

Dorsiflexion Assist AFO:

This AFO is very similar to the above AFO, but with a spring-like hinge that acts to raise the foot (dorsiflex the ankle) when the foot comes off of the ground. It offers the advantage of a more normal gait pattern. This is one of the best AFOs for patients with mild to moderate dropfoot and a flat or unstable foot. One of the better dorsiflexion assist AFOs is known as a “Richie Brace Dynamic Assist”. It allows for a very normal gait in patients with mild to moderate drop foot. It’s limitations are that it won’t work well for patients who weigh over 225 lbs or are over 6’ tall.

Dorsiflexion Assist AFO

 

Plantarflexion Stop AFO:

A “plantarflexion stop” AFO acts to stop plantarflexion by not letting the foot point downward. This type of AFO has a hinge that allows for normal dorsiflexion. Due to it’s somewhat bulky size, we don’t make this brace very often. It can be effective, however, for patients with more severe dropfoot.

Plantarflexion Stop AFO

Solid AFO:

This type of AFO stops plantarflexion and also stops or limits dorsiflexion. These are used for dropfoot patients with a nearly complete loss of dorsiflexion strength and who also have an unstable knee. It is a bit bulky, but gives a tremendous amount of control.

Solid AFO

 

Posterior Leaf Spring AFO:

This is a very traditional AFO and has been around for many years. We are not using many of these AFOs anymore as newer AFO models are often a lighter, more comfortable and easier to use. They are, however, often useful for some patients who have instability of the knee along with their dropfoot.

Posterior Leaf Spring AFO

 

Energy Return AFO:

This type of AFO uses a natural flex built into the material of the AFO to provide assist in dorsiflexion. These devices are often made of carbon graphite materials. We have used many of these prefabricated AFOs lately as they provide good control with very little weight. Depending on the degree of dropfoot, we choose one of three different models:

Energy Return AFODrop Foot Brace SeattleDrop Foot Seattle

 

4. Recovery and rehabilitation

Depending on the nature of the cause of foot drop, recovery can be partial or complete. Physical therapy and an ankle foot orthotic device worn in the shoe are important aspects of rehabilitation.

Best results will be achieved when a stable custom or prefabricated orthotic is worn on top of the foot plate of the AFO. If you do not have custom foot orthotics, we recommend that you use the PowerStep Medical Grade Orthotic. This is the best OTC arch support we have found. First place the AFO in your shoe. Then place this arch support on top of the foot plate of the AFO.

Best results will be achieved when a stable custom or prefabricated orthotic is worn on top of the foot plate of the AFO. If you do not have custom foot orthotics, we recommend that you use the PowerStep Medical Grade Orthotic. This is the best OTC arch support we have found. First place the AFO in your shoe. Then place this arch support on top of the foot plate of the AFO.

Once you get the AFO, arch support and socks, you will need to get a stable shoe that fits all three items along with your foot. It’s best to try them all on along with the shoe for best fit.

5. What research is being done?

The National Institute of Neurological Disorders and Stroke (NINDS) conducts research related to the neurological conditions that cause foot drop in its laboratories at the National Institutes of Health (NIH), and also supports additional research through grants to major medical institutions across the country. Much of this research focuses on finding better ways to prevent, treat, and ultimately cure the kinds of neurological disorders that cause foot drop.

 

 

reference: http://www.footankle.com/drop-foot.htm 
reference: http://www.orthoticshop.com/blog/afo-drop-foot-braces/

 

 

 

Comments  

 
+1 #2 Rosa Jones 2012-10-14 16:40
I am interested in the Dynamic Walk AFO. I currently have an ankle brace. Since I have a drop foot (cause: ruptured brain aneurysm), I would like to get a new AFO. Please provide guidance on how to acquire this device. Thank you.

Rosa M. Jones
5627 Ashleigh Park Dr.
Jacksonville, FL 32244
(904) 598-4053
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+1 #1 Al Caprio 2012-01-07 00:39
My Wife has a Solid-AFO drop foot with Knee weakness. Her toe drags and she has to use her hip to move her left leg. I need to find a better brace than the one
she now uses.
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