There is a lot of misinformation in the mainstream media when it comes to foot and ankle injuries. For example, I often see reports of professional athletes sustaining mid ankle sprains. There is no such thing as a mid ankle sprain.
In the interest of getting the medical terminology correct, here are the varying grades of ankle sprains and high ankle sprains.
Ankle Sprains
An ankle sprain involves injury to the stabilizing lateral ligaments of the ankle joint. It occurs when the foot is pointed downward and the ankle rolls inward (the classic ankle roll). Ankle sprains vary based upon how severely these ligaments are disrupted. Everyone heals tissue at different rates, thus return to activity is different for each patient. There are 3 grades of ankle sprains:
- Grade I – A mild sprain that involves no permanent damage to the ankle. It resolves in a few days to 2 weeks and almost never results in problems.
- Grade II – One or more of the major ankle ligaments have been disrupted (Anterior talofibular and calcaneofibular). Major symptoms resolve in 2-4 weeks or more. Long term problems of instability are common, but many muscular athletes can play through the instability for years. Accommodation using braces and strengthening different muscle groups can permit return to sports. But players often develop ankle spurs after 5-10 years.
- Grade III – A complete dislocation of the ankle joint. All the lateral ligaments are ruptured, more than 10% of the time bones are bruised, cartilage can be damaged, other tissues and tendons may be partially torn and nerves may be partially stretched. Some of these injuries cannot be seen on the MRI either. Often patients have gone to the hospital ER and been told nothing is broken. This is confusing as this injury can hurt more than some ankle fractures. Healing can take several weeks to months.
High Ankle Sprains
A high ankle sprain involves injury to a joint above the ankle, the syndesmosis, a tight tissue that holds the two bones of the leg (the tibia and the fibula) together. When the foot is at 90 degrees to the leg and twisted outwards, the two bones of the leg are stretched apart. Like ankle sprains, syndesmosis injuries are similarly graded.
- Grade I – Mild partial disruptions of one of the ligaments connecting the tibia to the fibula (usually only the anterior tibiofibular ligament). The joint is stable to a stress test and heals well within a few weeks.
- Grade II – Greater tissue disruption involving two of the three ligaments connecting the bones together. A stress test, weight bearing on the ankle, and checking for widening is unlikely to help since it is too painful in the acute setting. A stress test under anesthesia will demonstrate the injury. These injuries can also be diagnosed by MRI and in many cases are best treated with surgical stabilization. Regardless of treatment it can take 2 months or longer to return to sport.
- Grade III – Obvious dislocation of the tibiofibular joint. Surgery is indicated and return to sport is delayed 2-3 months.
