The peroneal tendons are two tendons that lie immediately behind the outside bone of the ankle (the fibula). These two tendons are responsible for moving the foot outwards in a direction called eversion.
They are important tendons because they balance the ankle and the back of the foot and prevent the foot from turning inwards repetitively. They are slightly weaker than the muscles and tendons on the inside of the ankle and are prone to injury as the ankle turns, rolls or becomes sprained.
Tears of peroneal tendons do occur. One or both of the tendons can be torn. Occasionally the peroneal tendons can be injured in either a fall or an athletic injury. They pop out of the supporting ligaments that hold them in place and dislocate.
Once this occurs, recurrent dislocation and tearing of the peroneal tendons is inevitable. If the peroneal tendons dislocate acutely in an injury, they need to be repaired to prevent future tearing of the tendons.
• Sense of instability behind the outside of the ankle
The diagnosis of peroneal tendon injury is made through careful examination and palpation by the orthopedic surgeon. An MRI may be required to more clearly document the extent of the tear.
Once a peroneal tendon tear is diagnosed, an orthopedic foot and ankle specialist should be consulted to determine the proper treatment.
In acute injuries, the ankle should initially be rested in a boot to allow the pain and inflammation to subside and then advanced to a brace and protected weight bearing. Physical therapy is necessary to restore motion and strength to the injured ankle. A shoe insert with a slight wedge may be helpful to further protect the tendons as the patient returns to athletic activity.
If pain persists after these conservative measures, surgery may be necessary. Usually the peroneal tendons can be repaired with stitches and the inflammation is removed from the tendon sheath.
If, however, the tendons are severely torn, they may need to be reconstructed with new tendon tissue. Sometimes this tendon tissue can be obtained from a tendon that is transferred from another part of the same leg. At other times allograft tendons are used. These come from the cadaver bank. The allograft tendons are safe to use, have no immunogenic properties and are not rejected.