Ankle Laxity

Cause
Ankle sprains are very common, and they usually heal with no residual problems. The ligaments that are injured on the lateral side of the ankle, the calcaneofibular (CF) and anterotalofibular (ATF) ligaments, have a good blood supply and want to heal.

In a few cases, however, the ligaments heal somewhat elongated. If that is the case, they will not provide the support that they should at the lateral ankle. Should this happen there may be pain by the anterior and lateral ankle, and a sense of “instability”. You may have apprehension about the lateral ankle “giving way”. Some patients have recurrent ankle sprains.

Treatment of Recurrent Sprains
The acute treatment for an ankle sprain is the same whether it is first time a sprain has occurred, or it is recurrent.

Once the ankle has settled down it is appropriate to evaluate it. The physical examination will usually demonstrate the laxity, or looseness, in the ankle ligaments.

Special ankle Xrays, called stress Xrays, can also demonstrate how loose the ligaments are. The ankle joint is forced forward and into inversion while the xrays are taken. If there is laxity in the ligaments, the talus bone will appear to shift under the tibia and fibula. The amount that it shifts will depend on how loose the ligaments are.

MRI studies are good to evaluate other causes of ankle pain after recurrent sprains, but they do not always accurately assess the ligaments.

Some cases of recurrent ankle sprains are due to functional laxity. If that is the case, the ligaments are normal, but the muscles about the ankle need to be trained to provide stability. That is best treated with bracing and physical therapy.

If there is anatomic laxity, the ligaments are too long, then the treatment options are bracing or Surgery to Tighten the Ligaments.