272 



MUSCLES OF THE SOLE OF THE FOOT. 



Fig. 110." 



The ABDUCTOR MINIMI DIGITI lies along the outer border of the 

 sole of the foot. It arises from the outer tuberosity of the os calcis, 

 and from the plantar fascia, as far forward as the base of the fifth 

 metatarsal bone, and is inserted into the base of the first phalanx of 

 the little toe. 



Relations. By its superficial surface with the external portion of 

 the plantar fascia. By its deep surface with the musculus accessorius, 

 flexor brevis minimi digiti, with the tarsal bones, and with the meta- 

 tarsal bone of the little toe. By its inner side with the flexor brevis 

 digitorum, from which it is separated by the vertical septum of the 

 plantar fascia. 



The FLEXOR BREVIS DIGITORUM 

 (perforatus) is placed between the two 

 preceding muscles. It arises from the 

 under surface of the os calcis, from the 

 plantar fascia and intermuscular septa, 

 and is inserted by four tendons into the 

 base of the second phalanx of the four 

 lesser toes. Each tendon divides, pre- 

 viously to its insertion, to give passage 

 to the tendon of the long flexor ; hence 

 its cognomen perforate. 



Relations. By its superficial surface 

 with the plantar fascia. By its deep 

 surface with a thin layer of fascia which 

 separates it from the musculus acces- 

 sorius, tendons of the flexor longus di- 

 gitorum and flexor longus pollicis, and 

 plantar vessels and nerves. By its 

 borders with the vertical septa of the 

 plantar fascia, which separate the 

 muscle, on th one side from the ab- 

 ductor pollicis, and on the other from 

 the abductor minimi digiti. 



Second Layer. 

 Musculus accessorius, 

 Lumbricales. 



Dissection. The three preceding 

 muscles must be divided from their 



origin, and anteriorly through their tendons, and removed, in order to 

 bring into view the second layer. 



* The third and a part of the second layer of muscles of the sole of the foot. 

 1. The divided edge of the plantar fascia. 2. The musculus accessorius. 3. 

 The tendon of the flexor longus digitorum. 4. The tendon of the flexor longus 

 pollicis. 5. The flexor brevis poliicis. 6. The adductor pollicis. 7. The 

 flexor brevis minimi digiti. 8. 1 he transversus pedis. 9. Interossei muscles, 

 plantar and dorsal. A convex ridge formed by the tendon of the peroneus lon- 

 gus muscle in its oblique course across the foot. 



