The Use of Foot Orthoses for Ankle Sprains
-
One of the most brilliant Podiatrists that I have ever known here presents an article on their use in the management of ankle sprains. Dr. Doug Richie, of Richie Brace fame, presents one of the few literature articles on the use of functional foot orthotic devices and for the purpose of foot stability when a patient becomes laterally unstable by definition. Here at KevinRoot Medical we have so many modifications to help you design a great orthosis to prevent that lateral foot ankle area from higher lateral heel cups, varying amounts of lateral flanges, zero motion rearfoot posts, lateral or valgus wedging, lateral frame fills, and more. Here is the abstract from his article:
“Chronic instability of the ankle can be the result of mechanical and functional deficits. An acute ankle sprain can cause mechanical and functional instability, which may or may not respond to standard rehabilitation programs. Chronic instability results when there is persistent joint laxity of the ankle or when one or more components of neuromuscular control of the ankle are compromised. A loss of balance or postural control seems to be the most consistent finding among athletes with chronic instability of the ankle. Recent research in patients with acute and chronic ankle instability has revealed positive effects of foot orthoses on postural control. This article reviews the current research relevant to the use of foot orthoses in patients with chronic ankle instability and clarifies the suggested benefits and the shortcomings of these investigations.”
Let’s review the difference between mechanical ankle instability and functional ankle instability. I typically explain to my patients who tear their lateral ankle ligaments in a sprain that they have mechanical failure or instability. The ligaments that protect the lateral ankle have been injured. But, what really sends people to the operating room is functional instability. Functional instability is the loss of lateral column stability where they can functionally re-sprain their ankle walking down the street. What are some of the reasons a patient would have functional instability with this typical lateral column overload?
When a patient presents to my office with lateral instability, I typically see contact phase supination (not the expected contact phase pronation) but not always. They may just feel unstable. What do I find that can cause this and what can help?
- Past History of Ankle Sprains (occasionally wearing an ankle brace in high risk activities). I probably will find a positive Varus Thrust or Anterior Drawer Test on examination.
- Weak Peroneal Tendons (these need to be strengthened, and if there is chronic mechanical joint laxity, that strengthening should be lifelong).
- Genu Varum or High Tibial Varum that puts excessive lateral overload on the foot (this alone typically needs 3 orthotic modifications to help with supporting the lateral column)
- High Forefoot Valgus/Plantar Flexed First Ray Deformity (I love to find this foot type in my patient that presents with lateral instability complaints. Good Root Balancing for these forefoot deformities does wonders to right the ship that leaning laterally as they walk).
- Hypermobility Patients (these patients have more stretch in their ligaments and are harder to stabilize, but you can with some thought. I love the deepest heel cups their shoes allow, zero motion posts, lateral frame fill aka Denton modification, wide frames, and proper Root Balancing traditional technique).
I hope Dr. Richie’s fine work has motivated us all to look at these ankle sprain patients with more determination to work on their functional instability. The task of single leg balancing can be game changing: from open eyes to closed eyes eventually. So much of the patient’s success is tied to how you emphasis it and keep emphasizing it in each followup visit.
