AFOs*, an ally for correcting foot drop

*AFO = Ankle Foot Orthosis

AFOs – what is it and what is it used for?

It's an orthopedic device designed to address the issue of foot drop effectively. When you have foot drop, your foot tends to point downwards, making it challenging (if not impossible) to lift it properly. This condition significantly impacts walking and can make it very difficult. For more information on foot drop, see our article "Foot drop, a weakness that prevents proper walking".

One of the non-invasive and non-pharmacological option is to wear an AFO. It maintains the foot in a neutral position ensuring a secure step and improving walking1, 6.

 

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How to choose an AFO?

There are many types of AFOs: 

  • to be positioned inside or outside the shoe; 
  • made of textile, plastic or composite materials (carbon fibre...); 
  • available in standard size or custom made; 
  • with or without an ankle joint; anterior or posterior.

Your healthcare professional will determine the most suitable type and shape for you.

How do AFOs work?

While foot lifters may vary in design, their primary objective remains the same: to enhance walking by lifting the foot6.

Many AFOs are L-shaped, with a sole that goes under the foot, a strut that runs down the leg and a shell, below the knee, as an attachment point around the leg. They can be of various stiffnesses depending on your condition, and most models only work when worn in a closed shoe.

The action between the foot and leg and the AFOs allows7

  • To maintain the ankle angle at 90° when walking; 
  • Depending on the model: to create a dynamic impulse at the end of the stance phase and therefore reduce fatigue & energy consumption8.

Understanding the gait cycle helps us comprehend when the AFO comes into play:

 

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AFOs: How to pick a model that fits me?

First of all, your healthcare professional will guide you through the selection process.

It is important to bear in mind that the AFO will be used systematically as soon as you walk. You must therefore make sure that you have an AFO that is: 

  • Neither too flexible nor too rigid: the foot must be raised but the orthosis must not hinder walking. 
  • Well-adapted, especially if you wear it daily, ensuring there are no points of contact with the skin outside the intended areas. 
  • Strong and resistant to support the weight of the body with each step and to ensure safe walking. 
  • The correct size: a device that is too small or too large can be uncomfortable and less effective.

To sum up, when choosing an AFO, the most important thing is to make sure you feel comfortable! Don't hesitate to discuss your options with your healthcare professional.

SOURCES
1: The Interdisciplinary Management of Foot Drop - Anne Elisabeth Carolus, Dr. med., Michael Becker, PD Dr. med., Jeanne Cuny, Dr. med., Rüdiger Smektala, Prof. Dr. med., Kirsten Schmieder, Prof. Dr. med., and Christopher Brenke, PD Dr. med. Dtsch Arztebl Int. 2019 May; 116(20): 347–354. Published online 2019 May 17. doi: 10.3238/arztebl.2019.0347 PMCID: PMC6637663 PMID: 31288916
2: Foot drop: where, why and what to do? - John D Stewart 1 - PMID: 18502948 DOI: 10.1136/jnnp.2008.149393
3: Treatment of foot drop in orthopaedic practice] - Marek Bielecki 1, Paweł Zebrowski, Anna Kuryliszyn-Moskal - PMID: 23289258
4: Evaluation and Treatment of Foot Drop Using Nerve Transfer Techniques - Arshad A Khan 1, Edgardo R Rodriguez-Collazo 2, Erwin Lo 3, Asim Raja 4, Sujin Yu 5, Hamid A Khan 5 - PMID: 33220746 DOI: 10.1016/j.cpm.2020.09.004
5: Trends and Technologies in Rehabilitation of Foot Drop: A Systematic Review - Fady Alnajjar 1 2, Riadh Zaier 3, Sumayya Khalid 1, Munkhjargal Gochoo 1 4 - PMID: 33249938 DOI: 10.1080/17434440.2021.1857729
6: Effect of ankle-foot orthoses on functional outcome measurements in individuals with stroke: a systematic review and meta-analysis Aliyeh Daryabor, Toshiki Kobayashi, Sumiko Yamamoto, Samuel M Lyons, Michael Orendurff, Alireza Akbarzadeh Baghban - PMID: 34482791 DOI: 10.1080/09638288.2021.1970248
7: Contribution of ankle-foot orthosis moment in regulating ankle and knee motions during gait in individuals’ post-stroke. - Toshiki Kobayashi, Michael S Orendurff, Madeline L Singer, Fan Gao, K Bo Foreman - PMID: 28431220 PMCID: PMC5494285 DOI: 10.1016/j.clinbiomech.2017.04.002
8: Alimusaj, M et al. “Funktionelle Auswirkungen des Einsatzes von Karbonfedern bei Unterschenkelorthesen” [Functional impact of carbon fiber springs in ankle-foot orthoses]. Der Orthopade vol. 36,8 (2007): 752-6. doi:10.1007/s00132-007-1125-0