OF THE SOLE OF THE FOOT THIRD LAYER. 



353 



Fig. 196. Muscles of the Sole of the Foot. 

 Third Layer. 



Third Layer. 



Flexor Brevis Pollicis. Flexor Brevis Minimi Digiti. 



Adductor Pollicis. Transversus Pedis. 



The Flexor Brevis Pollicis arises, by a pointed tendinous process, from the 

 inner border of the cuboid bone, from the contiguous portion of the external 

 cuneiform, and from the prolongation of the tendon of the Tibialis posticus, which 

 is attached to that bone. The muscle 

 divides, in front, into two portions, 

 which are inserted into the inner and 

 outer sides of the base of the first 

 phalanx of the great toe, a sesamoid 

 bone being developed in each tendon 

 at its insertion. The inner head of 

 this muscle is blended with the Ab- 

 ductor pollicis previous to its insertion ; 

 the outer head, with the Adductor 

 pollicis; and the tendon of the Flexor 

 longus pollicis lies in a groove between 

 them. 



Relations. By its superficial surface, 

 with the Abductor pollicis, the tendon 

 of the Flexor longus pollicis and plantar 

 fascia. By its deep surface, with the 

 tendon of the Peroneus longus, and 

 metatarsal bone of the great toe. By its 

 inner border, with the Abductor pollicis. 

 By its outer border, with the Adductor 

 pollicis. 



The Adductor Pollicis is a large, thick, 

 fleshy mass, passing obliquely across 

 the foot, and occupying the hollow space 

 between the four outer metatarsal bones. 

 It arises from the tarsal extremities of 

 the second, third, and fourth metatarsal 

 bones, and from the sheath of the tendon 

 of the Peroneus longus, and is inserted, 

 together with the outer head of the 

 Flexor brevia pollicis, into the outer 

 side of the base of the first phalanx of 

 the great toe. 



The Flexor Brevis Minimi Digiti lies 

 on the metatarsal bone of the little toe. 

 It arises from the base of the metatarsal 

 bone of the little toe, and from the 

 sheath of the Peroneus longus; its 

 tendon is inserted into the base* of the 

 first phalanx of the little toe, on its 

 outer side. 



Relations. By its superficial surface, with the plantar fascia and tendon of the 

 Abductor minimi digiti. By its deep surface, with the fifth metatarsal bone. 



The Transversus Pedis is a narrow, flat, muscular fasciculus, stretched trans- 

 versely across the heads of the metatarsal bones, between them and the flexor 

 tendons. It arises from the under surface of the head of the fifth metatarsal 

 bone ; and from the transverse ligament of the metatarsus, and is inserted into 

 the outer side of the first phalanx of the great toe ; its fibres being blended with 

 the tendon of insertion of the Adductor pollicis. 

 23 



