The peroneals are a fascinating group of muscles which are often overlooked when doing any self myofascial release work.
The peroneals are made up of two muscles peroneus longus and peroneus brevis.
The lower leg is made up three main compartments, anterior, posterior and lateral compartments. The peroneal muscles lie in the lateral compartment.
Peroneus Longus is responsible for everting the foot and helps with plantar flexion of the ankle (think bringing the outside of your foot off the ground while pointing your toes. This muscle attaches proximally on the upper fibula and wraps behind lateral malleolus (outside ankle bone), continues along the underside of the foot where it attaches distally on the first metatarsal and medial cuneiform.
The peroneus longus muscle is involved in primary ankle joint eversion and also plays a critical role in maintaining the foots lateral and transverse longitudinal arch of the foot.
Peroneus brevis also everts the foot and assists in plantar flexion of the ankle. It lies deep to longus and attaches proximally at the lower portion of the fibula. Peroneus brevis wraps behind the lateral malleolus (ankle bone) and attaches distally on the fifth metatarsal.
The peroneus brevis everts the foot and also plays a role in maintaining the lateral longitudinal arch of the foot.
Both peroneal muscles are supplied by the superficial fibular nerve (L5-S1).
The peroneals are seen mostly as primary ankle joint everters of the foot, a lesser known, yet very interesting fact about the peroneus longus muscle is that it helps in the stabilization of the big toe.
This stabilization plays a large role in the appropriate winding of the plantar fascia during gait, known as the windlass effect. This fact is what helps in stabilising the ankle joint by preventing inversion of the ankle during lateral and pivoting movements such as in soccer, rugby, tennis or basketball. As such Waveblade self myofascial release in this area is important for the prevention of ankle sprains injuries.