170 MUSCLE TISSUE 



that of the flexor longus hallucis, in each case super- 

 ficially. It divides into four parts for terminal phalanges 

 of the four lesser toes. 



Tibialis Posticus, beneath the two long flexors. 

 Origin, posterior surface of the interosseous membrane, 

 outer part of the posterior surface of the tibia below 

 the oblique line of the middle of the bone, whole inner 

 surface of the fibula, and from the aponeurosis over it. 

 Tendon along the inner border of the muscle, free at 

 the level of the lower tibiofibular articulation, passes 

 behind the inner malleolus, inserted into the tuberosity 

 of the scaphoid, with offsets to the three cuneiform, 

 to cuboid, to bases of the second, third, and fourth 

 metatarsals, and to the transverse tarsal ligament and 

 flexor longus hallucis tendon, and sends a thin process 

 back to the sustentaculum tali of the os calcis. 



Flexor Longus Hallucis. Origin, lower two-thirds of 

 the posterior surface of the fibula, septum between it 

 and the peronei ; aponeurosis common to it and flexor 

 longus digitorum. Tendon at the posterior surface 

 of the muscle traverses groove on the back of the 

 astragalus and under surface of the sustentaculum, 

 gives slip to the flexor longus digitorum in the sole 

 of the foot, and proceeds to the base of the terminal 

 phalanx of the great toe. 



Muscles of the Foot 



The Dorsal Region (Instep). Extensor Brevis Digi- 

 torum Pedis. Arises from forepart and upper and outer 

 surface of the os calcis, in front of the groove for the 

 peroneus brevis tendon, and from the anterior ligament 

 of the ankle. The tendon has several vertical leaflets 

 from which muscular fibers arise, dividing into three 

 bellies which unite with the outer border of the long 

 extensors for the second, third, and fourth toes. 



The Plantar Region (Sole). THE CENTRAL GROUP. 

 Flexor Brevis Digitorum and Flexor Accessorius Lum- 

 bricales. Four in number. Origin, at points of division 



