THE LOWER LIMB 551 



which passes between its upper surface near its final division and 

 the distal end of the first phalanx. The fibrous sheaths of the 

 tendons, as they pass along the plantar aspects of the toes, as 

 well as the accessories of these sheaths, correspond with those 

 of the fingers." As the long and short flexor tendons are about 

 to pass to the plantar aspects of the respective toes, and before 

 entering the fibro - osseous canals, each pair of tendons passes 

 through a short fibrous tunnel, corresponding in position with the 

 balls of the toes, and constructed in the following manner : 

 superiorly or deeply it is formed by a portion of the transverse 

 metatarsal ligament ; inferiorly or superficially by a digital process 

 of the central division of the plantar fascia ; and on either 

 side by the deep expansion of the digital process which joins the 

 transverse metatarsal Ugament and lateral metatarso-phalangeal 

 hgament. 



Abductor Minimi Digit! — Origin. — (i) The outer side and front 

 of the outer tubercle on the plantar aspfect of the tuber calcis ; 

 (2) the front of the inner tubercle ; (3) the external intermuscular 

 septum ; and (4) the external division of the plantar fascia, 

 more particularly the strong band which extends between the 

 outer tubercle of the os calcis and the tuberosity on the outer side 

 of the base of the fifth metatarsal bone. 



Insertion. — ^The outer side of the base of the first phalanx of the 

 httle toe, in conjunction with the flexor brevis minimi digiti. It 

 often takes attachment also to the base of the fifth metatarsal bone 

 on the outer aspect of its plantar surface. 



Nerve- sup ply. — ^The external plantar nerve. 



Action. — (i) To abduct the Uttle toe, and (2) to flex its metatarso- 

 phalangeal joint. 



Occasionally a fourth muscle is met with in the first layer, called the 

 abdactor ossis metatarsi quintl or Wood's muscle. It arises from the outer 

 tubercle on the plantar aspect of the tuber calcis, and from the adjacent 

 portion of the plantar fascia, and it is inserted into the tuberosity on the 

 outer side of the base of the fifth metatarsal bone. In most cases, however, 

 this muscle has undergone degeneration, and is only represented by the strong 

 band of the external division of the plantar fascia, which extends between the 

 outer calcaneal tubercle and the tuberosity on the outer side of the base 

 of the fifth metatarsal bone. 



Second Layer. — ^This layer consists partly of tendons and partly 

 of muscles. They are as follows : the tendon of the flexor longus 

 ■ hallucis ; the tendon of the flexor longus digitorum ; the flexor 

 or musculus accessorius ; and the lumbricales. 



Tendons of Flexor Longus Hallucis and Flexor Longus Digitorum. 

 — The tendon of the flexor longus hallucis, after leaving the 

 groove on the under surface of the sustentaculum tali of the 

 OS calcis, is directed forwards and inwards, lying in its course 

 between the two heads of the flexor brevis hallucis, and the 

 tendon of the flexor longus digitonun is directed forwards and out- 



trds towards the middle line of the sole. The two tendons^ 



