The peroneus longus tendon is a long band of tissue that connects lower leg muscles to the back of the ankle joint and the bottom of the foot. Along with its counterpart the peroneus brevis, the tendon supports the arch of the foot and stabilizes back and forth movement of the ankle. The peroneus longus is a relatively strong, thick tendon, so injuries resulting in tears are uncommon. If a tear does occur, however, pain, swelling, and loss of mobility can be extensive. A person can usually treat a mild peroneus longus tendon injury at home by keeping weight off the foot, applying ice and taking anti-inflammatory medications. A serious injury may require casting, bracing, physical therapy, and perhaps surgery to repair damage.
A peroneus longus tendon injury typically occurs with a badly sprained ankle. The tendon might be stretched beyond its normal range of motion, resulting in a partial tear. If a person knows that he or she rolled an ankle, it is important to immobilize the joint and keep weight off of the foot. Pain, tenderness, and gradually worsening swelling are common, but symptoms are usually bearable. Severe peroneus longus tendon tears result in sharp, excruciating pains and immediate swelling that need to be addressed at an emergency room.
Following a minor injury, an individual should try to rest the foot for several days and avoid wearing tight shoes. Applying ice packs, elevating the leg, and taking over-the-counter anti-inflammatory drugs can help to alleviate pain and swelling. Some people also find relief by alternating between ice and heat wraps.
Most mild injuries start feeling better in one to two weeks, but people should be careful about returning to activity right away. Supportive wraps and elastic ankle braces can help prevent re-injuring the tendon or ankle joint. Most doctors suggest performing light stretching exercises after swelling and pain subside to gradually rebuild flexibility.
If an injury is bad enough to warrant a trip to the hospital, a person can expect to receive a physical exam and other diagnostic testing such as an x-ray, MRI and/or ultrasound. A doctor tries to gauge the extent of damage to the peroneus longus tendon and surrounding structures. He or she may decide to immobilize the ankle with a plaster cast or soft splint and fit the patient with crutches. Following several weeks of rest and taking medications to relieve pain, the cast can be removed and the patient can begin exercising.
Surgery is only needed when the tendon is completely torn. A surgeon may try to reconnect it or replace it with grafted tissue from another tendon in the body. Recovery times can vary, but most patients need to wear casts for about two months and then participate in guided physical therapy to rebuild balance and strength.