Peroneal tendinopathy is an uncommon problem with the tendons on the lateral side of the ankle joint. The condition in most cases occurs in runners where the strains on these structures are so much higher. There are 2 peroneal muscles on the lateral side of the leg whose tendons move across the outside of the ankle joint with one tendon attaching on the lateral side of the foot at the base of the fifth metatarsal. The other tendon passes underneath the foot to connect to an spot near the middle of the arch of the foot. The muscles have several different functions, but a major one is to stop the ankle rolling outwards and winding up with a ankle sprain. Since they work hard at that action, the strain on the tendons might be too much for the tendon to tolerate and they are prone to peroneal tendonitis.
Commonly the condition commences with discomfort either over or just below the outside ankle bone with or without some mild swelling. In some the swelling develops later. With continued exercise the symptoms gets more persistent and progressively worse. A typical feature in those with peroneal tendinopathy is a lower supination resistance. This means that it's easy for the rearfoot to supinate or roll outwards. This will cause the peroneal tendons to be really active, so if you then combine it with higher level of sporting activity, then the tendon is at high risk for an overuse injury.
The treatment of Peroneal Tendinopathy in most cases starts with minimizing the stress by lessening exercise levels and also the use of footwear wedging or foot inserts to pronate or tip the foot inwards so the muscle doesn't have to work as hard. Ice and anti-inflammatory medicines could also help decrease the pain and inflammation. Over the medium to long term raising stress by the way of exercise needs to be put on the tendon in order that it can adapt to the strains placed on it. In a few circumstances, surgery is indicated.