What to Know About Peroneal Tendonitis

Medically Reviewed by Dany Paul Baby, MD on August 24, 2022
5 min read

You have thousands of tendons in your body. Tendons connect muscles to bones with tissue that is strong and flexible but not very elastic. Tendons are very strong, but they can be strained. The point where the tendon attaches to the bone is a frequent point of injury.

‌The peroneal tendons stabilize the foot and guard against sprains. When they become inflamed, moving your foot may be painful. 

Here's what you need to know about peroneal tendonitis.  

Two muscles, the peroneus brevis and the peroneus longus, attach to the lower fibula. Around the ankle, the muscles turn into tendons. The peroneus brevis tendon attaches to the little toe. The peroneus longus tendon extends under the foot and attaches to the arch on the other side. Both stabilize the ankle.

Inflammation of a tendon is called tendonitis or tendinitis. Peroneal tendonitis occurs when one or both of the peroneal tendons swell and become painful. 

Often, tendonitis results from repetitive activities or overuse, but sometimes, aging can also be a factor. As you get older, blood flow to your tendons decreases, and they become thinner and easier to injure. 

The main symptom of peroneal tendonitis is swelling and pain around the ankle. You may also have pain on the outside of the foot and moving up the lower leg, making it hard for you to run or walk. You may also have a tender area just behind the ankle bone. Your pain may be worse early in the morning. 

When the pain in your foot and leg develops gradually, it is probably due to overuse or repetitive motion. Sometimes, though, an acute injury such as an ankle sprain can cause the tendons to swell. 

Risk factors for peroneal tendonitis include:

  • Age over 40
  • Conditions such as arthritis or diabetes
  • Previous ankle injuries
  • High arches
  • Excess weight
  • Smoking

Athletes may get peroneal tendonitis if they:

Tendonitis is just one of several conditions affecting the peroneal tendon. Others are:

  • Acute tears. If the tissues of the tendon tear, you may experience weakness and instability of the ankle, as well as pain. 
  • Tendinosis. Sometimes, the tendon degenerates due to overuse, resulting in pain that comes and goes. The ankle may consequently be weak and unstable. 
  • Subluxation. This condition occurs when one or both of the peroneal tendons slip out of position. Besides the usual pain, swelling, and instability, you may feel a popping sensation as the tendon moves around the ankle bone. 

Because pain in the foot and lower leg can have many causes, it's important to see a doctor if you experience the symptoms described above. 

Your doctor will begin the diagnostic process by taking note of your medical history. Be prepared to tell your doctor when the pain began and whether it followed an activity or an injury. Your doctor will ask about any recent illnesses and what medications you have taken. Steroid injections and certain antibiotics can affect the tendons. 

Next, your doctor will perform a physical exam by pressing on the foot and asking you to perform ankle movements. Your doctor might use imaging to rule out an injury and to get more information about how your foot is functioning. Imaging could include:

The combination of medical history, physical examination, and imaging could pave the way for a peroneal tendonitis diagnosis.

Treatment for peroneal tendonitis begins with ice, rest, and anti-inflammatory medications. Rest is especially important, as the peroneal tendon can heal quickly if the tendons are given a chance to recover. 

Other conservative treatments include:

  • Compression. Use a compression bandage to reduce swelling.
  • Bracing. If your tendonitis is mild, you can use a brace to stabilize the ankle.
  • Immobilization. A boot or soft cast can allow tendons to heal.
  • Physical therapy. Exercises and stretching can help you recover your strength and range of movement.
  • Steroid treatment. In some cases, your doctor might recommend steroid injections.

If these treatments do not work, you may need surgery for peroneal tendonitis. Called a synovectomy, the surgery used to treat this condition involves removing the damaged tissue. Surgeons sometimes perform traditional open surgery and sometimes perform a less invasive type called arthroscopy. If you are a candidate for arthroscopy, you could have smaller incisions and a faster recovery time. 

Recovery from peroneal tendonitis usually takes around a month. Your doctor can tell you when it is safe to resume your normal activities, including running or playing sports. If you have surgery, your recovery will take longer. You'll be in a cast for 4 to 6 weeks, probably followed by physical therapy. 

If you have physical therapy as part of your treatment, with or without surgery, your physical therapist will probably give you exercises to do at home. Peroneal tendonitis exercises usually include stretching, resistance training, and range-of-motion exercises. You can use flexible tubing or a towel to provide resistance. A wobble board is also good for rehabilitation.

A conditioning program for your foot and ankle could help you avoid another injury. A typical program includes:

  • 5 to 10 minutes of low-impact activity like walking to warm up the legs
  • Stretching activities suggested by your doctor or physical therapist
  • Exercises to build strength and range-of-motion
  • A repeat of the stretching exercises

Typical exercises include:

  • Heel cord stretches. Face a wall with your unaffected leg forward and the affected leg back. Put your hands on the wall for support and press your hips forward while keeping your heels flat on the floor. This stretch can be done with the affected leg kept straight or slightly bent.
  • Calf raises. Hold on to the back of a chair. Stand on your affected foot and bend the other leg at the knee. Keeping your affected leg straight, raise and lower your heel. 
  • Ankle range of motion. Sit in a chair with your feet off the floor. Use the affected foot to trace the letters of the alphabet in the air. Keep your movements small.