160 ANATOMY IN A NUTSHELL 



occupies the hollow space between the four inner metatarsal bones. It is a 

 large, thick, fleshy mass passing obliquely across the foot. 



Origin. — (Plate LIII.) — Tarsal extremities of second, third, and fourth 

 metatarsals and sheath of tendon of Peroneus longus. 



Insertion. — ( Plate LIII.) — Outer side of base of first phalanx of great toe, 

 with outer portion of Flexor brevis hallucis. All the small muscles of the great 

 toe give off fibrous expansions at their insertion to blend with the long extensor 

 tendon. 



Action. — Abducts great toe. 



Nerve Supply. — External plantar. 



Blood Supply. — Plantar arteries. 



Adductor transversus hallucis. — Description. — (Plate LX.) — This muscle 

 is narrow ami fiat, and crosses the heads of metatarsal bones, lying between 

 them and the flexor tendons. Another name for this muscle is (Transversus 

 pe< lis.) 



Origin. — (Plate LIII.) — Inferior metatarso-phalangeal ligaments of three 

 outer toes. 



Insertion. — (Plate LIII.) — Outer side of first phalanx of great toe, its 

 fibers being blended with the tendon of insertion of the Adductor obhquus 

 hallucis. 



A< tion. — Adducts great toe. 



Xi;i;\ e Sipply. — External plantar. 



Blood Supply. — External plantar. 



Dorsal interossei. — Description. — (Plate LXI.) — The Dorsal interossei 

 of the foot are similar to those in the hand with the exception that they are 

 grouped around the middle line of the second toe, while those of the hand are 

 grouped around the middle line of the middle finger. Each one lias two heads 

 between which pass the perforating arteries to the dorsum of the foot, except in 

 the hirst dorsal interosseous between the two heads of which passes the com- 

 municating branch of the dorsalis pedis artery. 



ORIGIN. (Plate LXI.) — From adjacent sides of metatarsal bones. 



Insertion. — (Plate LXI.) — Bases of first phalanges and aponeurosis of 

 common extensor tendon; first muscle inserted into inner side of second toe, 

 the other three into outer side of second, third, and fourth toes. 



Action.— Flex first and extend second and third phalanges ; adduct second, 

 third, ami fourth tin-. 



Nerve Supply. External plantar. First and second dorsal also receive 

 extra filaments from anterior tibial nerve. 



Blood Supply. The Plantar interossei receive the external plantar, and 

 the Dorsal interossei receive the plantar arteries both external and internal; ex- 

 cept the third dorsal interosseous which receives the external only. 



Plantar interossei. DESCRIPTION.— (Plate LXII.) — The plantar inter- 

 ""i i ;ire three in number, the same as the palmar interossei of the hand and also 

 have one head apiece. They lie beneath the metatarsal bones. 



ORIGIN.— (Plate LXII.) Base ami inner side of shaft of third, fourth. 

 and fifth metatarsal bones. 



