What is peroneal tendonitis?
There are two peroneal muscles, in the outside (lateral aspect) of your leg. Their tendons travel down around the ankle and connect to the foot. The peroneus longus is longer and starts up near the knee. The peroneus brevis tendon is shorter, starting about halfway between the ankle and the knee.
Peroneal tendonitis is inflammation of the peroneal tendons in the foot.
Peroneal tendonitis usually causes pain along the outside of the foot, ankle or lower leg. Pain may be present with activity such as walking or standing. People with peroneal tendonitis often also have ankle instability and may have suffered an ankle sprain or multiple sprains.
Discomfort due to peroneal tendonitis will usually occur gradually, increasing over time if aggravating activities are continued. In the initial stage of the condition, pain is present with activity, but as the condition progresses pain will be felt even when resting. Over time the condition may progress to the point where the tendon begins to break down. The collagen fibers become disorganized and tendon may become prone to micro-tears. Continued degeneration is known as “tendonosis” and may ultimately lead to rupture.
Repetition and/or high forces can put excess tension on the peroneal tendons leading to damage and inflammation. Activities that are typically related to peroneal tendonitis are walking or running (particularly on uneven ground) or sports that involve frequent change of direction and lateral movement – such as basketball, netball, tennis.
People with high arched, supinated feet (feet that roll outward) can be prone to peroneal tendonitis due to tension on the peroneal tendons.
Some people with a certain type of “flat feet” or those whom have suffered ankle sprains may also be at risk of developing peroneal tendonitis. If you are taking steroids (prednisone) or flouroquinalone antibiotics (Cipro, Levaquin) you may be at elevated risk of tendon rupture.
Diagnosis of peroneal tendonitis is usually made on clinical examination, however referral for an MRI scan or ultrasound may be recommended to confirm the diagnosis.
Treatment can include:
- Rest and anti-inflammatory medication
- Exercises and stretching
- Ultrasound, heat or ice (depending on the injury)
- Footwear advice and orthotics to reduce tension on the peroneal tendons and prevent recurrence of the problem
- In some cases, a walking cast boot is necessary to take pressure off the injured tendon, while allowing it to heal
- Extra-corporeal Shock Wave Therapy
- Surgery is rarely necessary for this condition. In some cases however,the tendon will not repair without surgery.