Peroneal tendonitis is not exactly a very common problem is runners, but can be a difficult condition to manage if you look at some of the comments on blog posts about it from runners who have it. The peroneal muscles are on the outside of the leg and the tendons pass around the outside of the ankle joint. The peroneal muscles play a role to help turn the foot outwards and stabilize the foot when it is on the ground. They are one of the main ways in which ankle sprains are prevented. If there is a tendency for the ankle to rolls outwards and the muscles have to work hard to prevent it, then there is an increased risk of peroneal tendonitis from the muscles having to work so hard. The pain of this problem is usually either just above or just below the outside ankle bone. There may be some swelling. Initially the pain is only present when running, but later the pain persists after running. Increased activity levels also seems to increase the symptoms.
Treatment of peroneal tendonitis is to reduce activity level down to a level that is tolerable. It may be important to substitute an additional activity that does not load the tendons to maintain fitness. ICE and NSAID’s can also be helpful to reduce the inflammation and control the symptoms. Some clinicians advise the use of lateral wedging in the heel of the shoes to decrease the load in the tendon. Probably the most important part of the management is to once it starts to improve, that there is a progressive increase in load in the tendon so that the symptoms do not return. The tendons can adapt to the load if given time to adapt.