What is a Peroneal Tendon Injury? A strain is an injury caused by stretching, fraying or tearing of a muscle or tendon, usually caused by an external force on the body. The peroneal tendons are two tendons that lay on the outside of the ankle, just behind the fibula (one of the two bones of the lower leg). Tendons connect muscle to bone and allow the dispersion of force across a joint, necessary for movement. The peroneal tendons are responsible for turning the foot outwards. These tendons are usually strained by a stretching mechanism, such as when the ankle is turned inwards and rolled under the leg (the same mechanism as a lateral ankle sprain). Other ways the tendons may be injured are from excessive running on sloped surfaces, or from improper running mechanics. It is possible for the tendons, following injury, to begin sliding out from behind the fibula during movement. This is called “subluxing” of the peroneal tendons. If this occurs, the athlete will normally describe a snapping or popping sensation with ankle movement or during walking. Causes Twisting of the root inwards and underneath the leg (lateral ankle sprain mechanism) A sudden activity that forces your foot upward towards your shin (hard landing from height or sport) Excessive running on incline surfaces Improper running mechanics/footwear Signs and Symptoms There may be an audible pop or snap heard at the time of injury Pain on the outside of the ankle, especially behind the fibula Possible swelling over the outside aspect of the ankle and lower leg Pain with turning the toes outward Treatment Peroneal tendon strains are treated similar to ankle sprains, in the fact that they are normally managed conservatively with rest and appropriate treatment to diminish swelling. Ice, compression and elevation are important as well as rest from any aggravating activity. If the injury is severe enough to inhibit weight bearing, utilization of crutches or a walking boot is common, especially in the acute phase following injury. Once swelling and pain is decreased, it is important to begin to regain normal ankle range of motion as well as proper ankle mechanics and strength for further participation in sport; this is usually accomplished through a bout of physical therapy and home exercises done daily. Peroneal subluxations are also commonly treated similar to tendon strains, with conservative treatment focused on rest and rehabilitation. If no improvement is made with physical therapy, and snapping and pain continues, surgical intervention is often necessary to put the tendons back in their normal position and tighten the structure that normally holds them in place.