Muscle of the Month: Peroneals (Longus, Brevis and Tertius)
Your peroneals are the three muscles that sit on the outer side of your lower leg. They are also known as fibular muscles, as they run along your fibula, the outer bone in the lower leg. The three muscles are categorized by lengths: longus, the longest of the three; brevis, the shorter one; and tertius, the third of the peroneals that attaches to the lower third of the fibula.
Actions: To evert the foot (bring outer edge towards the ceiling) and to plantar flex the foot (point).
Common Pain Culprit: Activities that use lots of ankle motion (walking on uneven surfaces, marathon runs, etc.), and high arches.
The most common injury to the peroneals is tendonitis, the inflammation of a tendon. This is due to the unique position of the peroneal tendons. As they travel on the outside of the leg, they make a 90 degree turn around your lateral malleolus (the big bump on the outside of your ankle) and attach into the bottom of the foot. Repetitive ankle movements cause excess friction along these tendons, which can lead to inflammation. You will primarily feel the pain along the tendon pathway (around the malleolus), but sometimes also in the muscles themselves. Peroneal tendonitis can sometimes be confused with Cuboid drop (which is the misalignment of one of the most lateral foot bones), as it can radiate pain into the same area.
Actions: To evert the foot and dorsiflex foot (point toes towards the ceiling).
Common Pain Culprit: Excess dorsiflexion, for example from prolonged or intense walking.
Although it is part of the peroneal group, Peroneus tertius acts more like the extensor digitorum longus (the big toe extensor, which points the foot and toes up to the ceiling). The tendon of the peroneus tertius doesn’t make the 90 degree turn around the malleolus, but goes above it to attach in the same area as the EDL – the base of the fifth toe – giving it the ability to bring the foot to the outside and toes to the ceiling, an important action in walking.
The fix: Ice, massage, strengthening, good footwear, bracing.
When a tendon is acutely inflamed, ice can decrease the pain. Rolling ice over the muscle belly, or strapping it down to the ankle, can both help alleviate acute pain symptoms.
A good massage and a strengthening program can help the injury during the later stages of healing. Massage can break down excess scar tissue that has formed, and lengthen the muscle. Strengthening the muscle can prevent further damage or future injury.
Proper footwear or bracing and taping can also help. Having the foot’s arch supported and the ankle secure can speed up healing and prevent more damage.
If you suspect peroneal issues, speak with your massage therapist, who can help isolate the affected muscle and provide a means of recovery through treatment and care recommendations.