A Guide To Conservative Management Of Lateral Ankle Sprain
Ankle sprains can be a very difficult podiatric problem to treat. This is because most of the time the treatment is not provided soon enough. Patients think an ankle sprain will heal on its own. Acute ankle sprains that are left untreated lead to chronic ankle instability. This can lead to many problems down the road, such as being prone to ankle injury/ankle fractures, osteochondral lesion, chronic pain, peroneal tendonitis. Chronic instability can lead to the need for surgical reconstruction.
What is an ankle sprain?
An ankle sprain simply is a partial dislocation at the ankle joint. The most common ankle sprain happens in the form of an inversion injury where the talus is pushed anterior and rotated internally compared to the tibia. This puts strain on our lateral ligaments and tendons. The ligaments include ATFL (Anterior talo-fiblar ligament), CFL (calcaneofibular ligament) and the PTFL Posterior tibio-talar ligament). The tendon includes the peroneal brevis and peroneus longus.
The inversion sprain though less common can be far more problematic. The medial ligaments also known as the deltoid ligaments are far stronger. There for when they are sprained they are usually accompanied by medial malleolus fractures.
Grading for sprains is simple. Grade 1 is a minor strain with no tear. Grade 2 is a partial tear. Grade 3 is a full tear. Often, the level of pain in a grade 3 full tear is less than a partial tear and results in the patient seeking less treatment.
How to perform a physical exam?
Early diagnosis and treatment are key for treating ankle sprains. We first start with a good history and physical to determine the mechanism of injury as stated above. Both ankle and foot x-rays should be taken. Ankle sprains can be associated with other injuries such as ankle fracture, syndesmotic injury, talar osteochondral lesions, 5th metatarsal base fractures, and even lis-franc injuries. These injuries can be missed and lead to severe complications if not caught. During the acute injury phase, I do not recommend performing the anterior draw test. This test determines how bad the ATFL is injured. But patients will not be able to tolerate this due to pain and muscle guarding. diagnostic ultrasound can help diagnose and visualize the peroneal tendons and posterior tibial tendons. But this exam is limited and if you suspect an injury that requires surgery, get an MRI or CT for better visualization.
How to Treat Ankle Sprains?
These studies showed that various forms of removable external ankle support, including the Air-Stirrup Ankle Brace (DJO Global), lace-up braces and taping, were all more efficacious than long-term cast immobilization. All studies incorporated early weight-bearing in the treatment. Even severe Grade III ankle sprains appear to heal better with early weight-bearing.18-19 Researchers have shown that early weight-bearing optimizes positioning of the torn lateral collateral ankle ligaments for healing while encouraging ankle dorsiflexion and restoration of the “close pack” position of this joint. But a small period of 10 days with strict immobilization, below the knee cast is recommended and leads to better functional outcomes. Patients are placed on NSAIDs to help with the inflammation and told to RICE( Rest Ice Elevate Compression). Surgery is not warranted unless of course the injury is associated with an unstable ankle fracture, then surgical intervention is warranted. Time for healing should go as follows Grade 1 4-6 weeks, Grade 2 6-9 weeks, Grade 3 around 10-14 weeks. But Ligaments can take up to a year before they are restored to original strength.
After the first 10 days of immobilization in the inflammatory phase, we move on to the proliferative phase. This is when we start having the patient be weight-bearing in a cam walker boot and are given an ankle lace-up brace. Patients are to be in the cam walker boot for all weight-bearing, For grade 1 & 2 this phase can last 4-6 weeks but for Grade 3 can be as long as 2-3 months. The boot can be taken off and patients are allowed to do passive ankle dorsiflexion and plantar flexion. Physical therapy should be started as soon as the patient can tolerate walking. But one must be careful to not start eversion and inversion exercises against resistance to early. I recommend starting those around week 4-6.
Patients can start transitioning to full weight-bearing into shoes at 4 weeks. But the ankle support brace needs to be worn at all times. Since it takes up to a year for ligaments to return to their original strength we recommend that patients wear the ankle brace for a full year. During the whole time, the patient should be doing RICE.
Summary
Recent trends point to the treatment of the lateral ankle sprain focusing on the basic science of ligament healing. The initial treatment for Grade II and III ankle sprains should be strict immobilization for seven to 10 days before allowing any motion across the ankle joint. We think long-term protection of the ankle is achieved by having removable braces for all athletes returning to the sport after a serious sprain. Early weight-bearing, functional rehab, and balance training is the key to treating the ankle sprain.
