The peroneus muscles are consist of three muscles and it also called fibularis. Peroneus is derived from the Greek word for fibula, indicating the location of the peroneal muscles. 1. Peroneus Tertius (fibularis Tertius) 2. Peroneus brevis ( fibularis brevis) 3. Peroneus longus (fibularis longus) 1. Peroneus Tertius (fibularis Tertius) Origin – anterior distal fibula(with extensor digitorum longus) Insertion – the base of 5 th metatarsal Nerve supply – deep peroneal nerve(l4,5,s1) Action – eversion of the foot, assist dorsiflexion Palpation – tendon palpated lateral to extensor digitorum longus tendon on dorsum of foot at base of 5 th metatarsal. This muscle functions to place the foot flat on the ground by raising the lateral border. 2. Peroneus brevis (fibularis brevis) Origin – lateral shaft of the fibula (lower 2/3) Insertion – the base of 5 th metatarsal Nerve supply- superficial peroneal nerve (l4,5,s1)