Popliteus muscle the ankle. The gastrocnemius muscle acts on both joints. It originates from the lateral surface of the lateral condyle of femur by a rounded tendon, the fibers pass downward and medially and give insertion to the posterior surface of tibia, above the soleal line. The muscle arises within the capsule of knee joint and its tendon separates the lateral meniscus from the lateral ligament of the joint. Nerve supply is via the tibial nerve from spinal roots L5 and S1. There is sometimes an additional head from the sesamoid bone in the lateral (outer) head of the gastrocnemius muscle. Rarely
Superior oblique muscle Superior oblique muscle The superior oblique muscle, or obliquus oculi superior, is a fusiform muscle originating in the upper, medial side of the orbit (i.e. from beside the nose) which abducts, depresses and internally rotates the eye. It is the only extraocular muscle innervated by the trochlear nerve (the fourth cranial nerve). The superior oblique muscle loops through a pulley-like structure (the trochlea of superior oblique) and inserts into the sclera on the posterotemporal surface of the eyeball. It is the pulley system that gives superior oblique its actions, causing depression of the eyeball despite being inserted on the superior