Ankle sprains can happen all of the time, but what is an ankle “sprain”? A traditional ankle sprain occurs along the outside of the ankle at the lateral ankle ligaments during an inversion injury. The foot rolls inwards and causes a stress across these ligaments that can stretch them or even tear them. Ankle sprains can range from mild sprains that get better with rest to ankle ligament tearing and ultimately ankle instability.
So what’s the difference? Let’s start by talking about the anatomy of the ankle joint. The ankle joint is made up primarily of the lateral malleolus (fibula), medial malleolus and tibia bone, medial malleolus and talus (ankle bone). The tibia and fibula are held together at the end of the ankle by the distal anterior and posterior syndesmotic ligaments. A series of ligaments on the outside of the ankle hold the talus and the calcaneus (heel bone) to the ankle. These ligaments are known as the lateral ankle ligaments: The Anterior Talo-Fibular Ligament (ATFL), Calcaneal Fibular Ligament (CFL) and the Posterior Talo-Fibular Ligament (PTFL). The inside or medial ankle ligaments are known collectively as the Deltoid Ligaments, but are rarely involved in ankle sprains.
The most commonly injured ligament is the Anterior Talo-Fibular Ligament (ATFL). The ATFL works like the ACL in the knee, it keeps the ankle joint from moving forward and adds stability during gait. Without this ligament, the talus is able to pull forward out of the ankle joint. More severe sprains can involve the CFL and PTFL as well. If the sprain involves the syndesmotic ligaments, it is referred to as a “High Ankle Sprain”.
Ankle sprains are classified by the severity of damage to the tissue. A grade 1 sprain is a pulling of the tissue causing stretching and pain. This injury is often painful but can be walked on and is treated with rest, immobilization, physical therapy, icing, NSAIDs, bracing and protection.
Grade 2 injuries involve a partial tear of the ligaments. This injury is more severe and may be difficult to walk on. MRI or ultrasound may be required to diagnose this injury. In a partial tear, there may be some instability in the ankle causing increased pain and requires a greater amount of time to heal. The standard of care is to treat these injuries with immobilization/casting, physical therapy and possible surgical intervention.
Grade 3 injuries are complete tears of the ligament. This can lead to severe instability in the ankle and pain. If the CFL is involved, the instability may also occur in the foot. These ligament injuries are diagnosed by physical exam, x-ray, MRI or ultrasound. The treatment for these injuries involves immobilization in a cast NWB and or surgery. Physical therapy needed after to regain functionality in the ankle and prevent further injury. Tears to the CFL or syndesmotic ligaments almost always require surgery, especially in the athletic population. Untreated ligament tears can result in damage to the joints, arthritis and chronic pain.
There have been several surgeries developed to treat ligament tears after ankle sprains. The Brostrom technique is the most common, involving the direct repair of the ATFL with or without graft. The tissue is repaired anatomically and re-secured to the point of attachment in the fibula using bone anchors. Some other techniques involve augmenting the ligament repair with nearby tendons or using grafts to augment the repair. Internal suture “braces” have also been used to supplement the ligament repair and decrease ankle instability.
More recent techniques involve ankle arthroscopy and direct repair of the ankle ligaments through the scope. This technique is known as the “Arthro-Brostrom” and involves less tissue dissection, quicker healing times, stable repair and quicker return to activity. A study published in The Journal of Foot and Ankle Surgery July/August 2018 by Hassan et all found no difference between open and arthroscopic repair in the overall stability of the ankle after repair. In other words, both techniques achieve the same results, but the arthroscopic technique is far less invasive.
Patients who have suffered severe ankle sprains should be evaluated by their Podiatrist. Other injuries may occur along with ankle sprains such as ankle fracture, cartilage damage (OCD) or foot fractures. Patients should also get evaluated if they have continued pain after a previous ankle fracture. Ligament repair can be performed for ankle instability despite the age of the injury. Regenerative medicine such as PRP or amniotic injections may also be utilized to help repair damaged ligaments.
We are one of the only clinics in the Phoenix area currently performing the Arthro-Brostrom. I have performed many of these procedures in the past 10 years with great patient satisfaction. This procedure is beneficial for new injuries, old injuries, chronic instability and patients of all activity levels. To learn more, schedule your appointment today at (480)-632-5757
Chris Suykerbuyk, DPM, FACFAS