OCR Text |
Show 1894.] ANATOMY OF PALAMEDEA CORNUTA. 551 Gastrocnemius.-The outer head is entirely tendinous, and arises from the femur distal to the long head of the biceps sling. The short arm of the biceps sling arises from the underside of this head of the gastrocnemius very close to its origin. From this short arm of the sling a broad tendinous band, thicker at the lower edge, runs in to join the origins of the perforated and perforating muscles. The outer head becomes tendinous halfway down the leg, and joins the tendo Achillis just above the ankle. The middle head arises tendinously from the inner condyle of the femur in common with the accessory semitendinosus, with which it is fused. It is joined by tbe outer adductor and by the tendon of the semitendinosus. This muscle then passes into a tendon which joins the tendon of the tibial head halfway down the leg. The inner or tibial head arises fleshy from the crista tibice and from the fascia covering the peroneus longus • it then joins the middle head. It is the broadest and strongest part of the gastrocnemius. Soleus.-This small muscle arises by a fleshy head from the tibia for a space of three quarters of an inch below its head on the inner face. Its long slender tendon is inserted on the under and inner surface of the ankle-cartilage. Peroneus longus.-This arises from the fascia covering the tibialis anticus, and from a small part of the upper end of the fibula, from the fascia over the knee-joint, and from the septum between itself aud the perforated and perforating flexor of the index. Its broad thin tendon sends a wide fork to the cartilage of the ankle-joint, and a narrower tendon which joins the tendon of the perforated muscle of the third digit. Tibialis anticus.-This has two muscular bellies : the smaller and rounder arises by a strong tendon from the outer condyle of the femur; the inner springs fleshy from the crista tibiae. The muscular part of the two heads unite halfway down the leg, and give rise to a strong tendon which is bifid just at its insertion. Through this fork a nerve passes. Extensor communis digitorum.-This arises fleshy from the tibia from its crest and from halfway down the shaft exactly under the tibial head of the tibialis anticus. Its tendon passes through first a bony and then a membranous bridge, and then runs down the anterior surface of the foot. Halfway down the tarsus metatarsus it divides in two. Each branch again forks. The forks of one branch are inserted on the second and third digits; the forks of the other branch on the third and fourth digits. Peroneus brevis.-This very slender muscle arises from the anterior face of the fibula and a small portion of the tibia. Its tendon is inserted on to a knob on the outer side of the tarsus metatarsus. Flexor perforans et perforatus indicus.-In the woodcut the perforated and perforating flexors are distinguished by the figure 2 placed before the roman number, which indicates the digit to which they are attached, while the perforated flexors are distinguished by the figure 1 correspondingly placed. This is the most superficial of the flexors; it arises from the outer condyle of 36* |