Tendonitis and strains are two of many issues that can potentially affect the peroneal tendons of the feet. These two tendons run side-by-side in the foot, with one attaching on the outer portion of the midfoot and the other running along the bottom of the foot and attaching on the inner portion of the arch. The main job of the peroneal tendons is to stabilize and protect the foot and ankle. When one or both of the tendons become inflamed, peroneal tendonitis occurs. This condition usually results from activities that require repetitive use of the tendon or trauma such as an ankle sprain. Symptoms of tendonitis include pain, swelling, and heat at the site of the issue. Strains and tears also can be caused by repetitive activity or acute trauma. Symptoms of strains include pain, swelling, and weakness or instability at the site of the injury. Proper diagnosis of peroneal tendon issues is crucial to proper treatment of the specific injury or condition. This can be achieved through a thorough physical examination as well as advanced imaging studies, including X-rays. Treatment will vary depending on the type and severity of the issue and may involve immobilizing the foot and ankle using a cast or splint, administering oral or injected anti-inflammatory medications, bracing, and participating in a physical therapy program to strengthen muscles and improve range of motion and balance in the area. In severe cases, surgery may be required to repair the tendon.