Understanding Ankle Sprains: Causes, Types, and Treatment Options

One of the most common injuries of the lower extremity is the ankle sprain. It is estimated in the general population (excluding athletes) there are approximately two million acute ankle sprains per year. Emergency room data shows that there are roughly 2-7 ankle sprains per 1,000 people. This is probably an inaccurate method of measuring the true incidence of ankle sprains because many people do not present to the emergency room for treatment. Chances are you have experienced an ankle sprain at some point in your life. Needless to say, this is a common ailment that deserves our attention and medical treatment. 

What is an Ankle Sprain?

To first understand what an ankle sprain is, we must first have a general understanding of the anatomy of the ankle. The ankle is a hinged joint, yet it functions in all three planes of movement, but primarily in the sagittal plane. It is this functionality that allows you to point your toes down or to pull your foot up. Because the ankle joint has motion in all three planes, it is imperative that strong ligaments stabilize the joint, otherwise every stray pebble we stepped on may result in disastrous consequences. The stabilizing ligaments on the inside of the ankle are known as the deltoid ligaments (do not confuse this with the deltoid muscle of the shoulder complex). The ligaments on the outside of the ankle are known as the lateral ankle ligaments. There are three main ligaments, each has a name, but for the purposes of this post, we won’t get into the details. 

Often a sprain is defined as an injury to the soft tissue supporting structures of a joint such as the ligaments we just described. Most commonly in the case of an ankle sprain, it is the outside or “lateral” ankle ligaments that are most often injured. The deltoid ligament complex can be injured as well, but this is rare as these ligaments are very strong. So simply put, an ankle sprain is an injury to the ligaments and supporting soft tissue structures of the ankle, most commonly the outside ligaments.

How does an Ankle Sprain Occur?

If you have ever had an ankle sprain, think back on how it occurred. Likely you stepped off a curb wrong, or maybe you stepped on an uneven surface when the injury occurred. As the injury was occurring you probably noticed your foot bending inwards, and your ankle rolling outwards. This is called an inversion ankle sprain, and it predominates as the most common type of ankle sprain. As we mentioned earlier, the deltoids ligament complex is very strong and usually the outside ankle ligaments are where instability of an ankle joint lies. These outside ankle ligaments are responsible for keeping your foot from “inverting” or rolling in too far, but because of the force of the injury or even some intrinsic weakness of the ligaments themselves, they can often be overpowered resulting in the injury.

Are all Ankle Sprains Treated the Same?

Ankle sprain treatment varies depending on the severity of the injury. When you see your doctor, you may hear them reference the injury according to various grades based on severity, they are as follows:

Grade I: Partial Tear of ligament; Mild Tenderness, Mild Swelling, Slight/no functional loss (can weight bear and ambulate with minimal pain), No mechanical instability (negative stress exam)

Grade II: Incomplete tear of ligament with moderate functional impairment. Moderate pain and swelling. Mild/Moderate bruising.  Some loss of motion/function. Mild to moderate instability. 

Grade III: Complete tear with loss of ligament integrity. Severe Swelling, severe bruising, Loss of function/motion, Mechanical instability. 

As you can see, not all ankle sprains are created equal, and as such the treatment varies according to injury severity. 

How Does My Dr. Determine What Grade of Ankle Sprain I Have?

During your visit, your doctor will ask several questions concerning the time of the injury. He will likely ask how the injury occurred and what position your foot was in as the injury was occurring. Additionally he will want to know if you were able to bear weight on the injured foot after the injury and up to the time of the visit. All of this will clue your doctor into how severe the injury was at the time of occurrence. 

In addition to a thorough history, your doctor will perform a thorough physical exam. He will observe any residual swelling, bruising, and areas of pain or tenderness overlying the ligaments in question. He may also test the stability of your ankle to assess the integrity of the ligaments to help determine a possible complete rupture or tear. 

To assist in the diagnosis and to rule out other possible problems, such as an ankle fracture, he will likely want to take an x-ray. If this is a chronic issue that keeps occurring, he may order an MRI to visualize the ligaments themselves, and to assess for rupture or incomplete tear.

What is the Treatment of an Ankle Sprain? 

To understand the treatment’s your doctor may recommend, we will break it down according to which grade of ankle sprain you have as previously discussed.

Grade I: Your doctor will recommend rest, ice, compression, and elevation for the first 12-48 hours. Likely there will be no need for immobilization or splinting/bracing. Usually you can expect full recovery after 1-3 weeks. 

Grade II: Your doctor will recommend rest, ice, compression and elevation for 12-72 hours. You will likely need immobilization in a walking boot anywhere between 2-6 weeks, with an ankle brace required for extra stabilization thereafter for 1 to 4 weeks. Usually with these injuries, physical therapy is recommended for 2-6 weeks. You can expect recovery within 3-12 weeks.

Grade III: Your doctor will recommend rest, ice, compression and elevation for 1-7 days hours. You will likely need immobilization in a walking boot anywhere between 3-6 weeks. In some cases, surgery may be indicated (more on that later) with an ankle brace required for extra stabilization thereafter for 1 to 6 months. Usually with these injuries, physical therapy is recommended for 4-8 weeks. Total recovery, depending on if surgery is required, is between 2-6 months.

What are the Possible Surgical Treatments Options?

As mentioned above, in severe injury patterns, surgery may be required. Best practices usually involve an ankle arthroscopy paired with a lateral ankle ligament reconstruction. The ankle scope is performed to rule out/treat injuries to the joint surface that often occur during severe ankle injuries. As mentioned earlier, grade three ankle sprains result when the ligament is fully ruptured. If not repaired or replaced, you will continue to experience ankle instability and the chances of repeated injury increase substantially. Often the ligament is directly repaired if possible or a non-absorbable synthetic material is utilized to replace the ligament. Your doctor will discuss the pro’s and con’s of each procedure and will educate you on the details of the procedure.

Conclusion

As you can see, the ankle sprain is not only commonplace, but can be severe and debilitating. There are several conservative treatment options available with many proven surgical options if conservative therapy fails. Don’t let an ankle sprain get in the way of doing the things you love. If you have a history of repeated ankle sprains or have recently experienced a bad ankle sprain, don’t hesitate to call and schedule an appointment at Northern Montana Foot and Ankle Specialists at (406) 257-8686. Dr. Jenkins and Dr. Webb are board qualified foot and ankle surgeons who have extensive training in all ailments of the foot and ankle. We look forward to meeting you.