Triceps surae muscle Triceps surae muscle The triceps surae is a pair of muscles located at the calf - the two-headed gastrocnemius and the soleus. These muscles both insert into the calcaneus, the bone of the heel of the human foot, and form the major part of the muscle of the posterior leg, commonly known as the calf muscle. The triceps surae is connected to the foot through the Achilles tendon, and has 3 heads deriving from the 2 major masses of muscle. The triceps surae is innervated by the tibial nerve, specifically, nerve roots L5–S2. Contraction of the triceps surae induce plantar
Opponens pollicis muscle Opponens pollicis muscle The opponens pollicis is a small, triangular muscle in the hand, which functions to oppose the thumb. It is one of the three thenar muscles, lying deep to the abductor pollicis brevis and lateral to the flexor pollicis brevis. The opponens pollicis originates from the flexor retinaculum of the hand and the tubercle of the trapezium. It passes downward and laterally, and is inserted into the whole length of the metacarpal bone of the thumb on its radial side. Like the other thenar muscles, the opponens pollicis is innervated by the recurrent branch of the median nerve.