MYOLOGY 119 



Shape. A broad muscular sheet. 



Action. Assists the flexor perforatus medius primus pedis. 



Tibialis Anticus (Fig. 24, No. 22). Location. In the anterior 

 tibial region. 



Origin. The muscular belly may be easily divided into two parts. 

 The inner head extends from the head of the tibia immediately 

 beneath the peroneus longus. The outer head arises by a strong 

 tendon from a depression on the antero-inferior ridge of the outer 

 condyle of the femur. 



Insertion. The tendon passing through the fibrous ligamentous 

 loop just above the tibial condyles, inserts to a tubercle on the 

 shaft just below the head of the tarso-metatarsus. 



Shape. Large, fusiform. 



Relations. Beneath the peroneus longus. 



Action. Flexes the metatarsus upon the tibia. 



Extensor Longus Digitorum (Fig. 25, No. G, 6). Location. An- 

 terior tibial region. 



Origin. From the inferior portion of the crest and a portion of 

 the shaft of the fibula. 



Insertion. It becomes tendinous at the lower third of the bone, 

 passing under the bony ridge just above the condyle in front, 

 and over the ankle-joint. It is bound down by firm fascia, and at 

 the trochlea of the basal toe joints, divides into three small tendin- 

 ous slips. These pass over the superior part of the second, the 

 third, and the fourth toes, bifurcating in their course, and are 

 inserted to the distal ones. 



Shape. Long, penniform, with a long, slender tendon. 



Relations. Immediately below the tibialis anticus. 



Action. Extends the digits as their long extensor. 



Extensor Hallucis Brevis (Fig. 25, No. G, 4). Location. The 

 anterior metatarsal region, along- the antero-internal edge. 



Origin. From just below the summit of the antero-internal part 

 of the head of the tarso-metatarsus, and from the adjacent shaft 

 below, and from the tendon of the tibialis anticus. 



Insertion. Into the process at the superior part of the bone of 

 the bony claw of the hallux. 



Shape. Slender, thin in diameter, with a long, slender tendon. 



Relations. Superiorly, with the antero-internal edge of the 

 metatarsus and inferiorly, its tendon with the top of the hallux. 



Action. Extends the hallux. 



