SOLE OF THE FOOT 291 



nerves will be seen piercing the deep fascia in order to reach the skin. 

 Towards the heads of the metatarsal bones the metatarsal arteries and 

 the common plantar digital nerves are unprotected by the aponeurosis, 

 and the dissector must proceed cautiously. The nerves and vessels 

 which go to the medial side of the great toe and to the fibular side of 

 the little toe are especially liable to injury, as they perforate the fascia 

 farther back than the others. A band of transverse fibres, which crosses 

 the roots of the toes and lies over the digital vessels and nerves, should be 

 noticed. It is the superficial transverse ligament of the toes. It is closely 

 connected with the skin where it forms the cutaneous webs between the 

 toes. By forcibly separating the toes its connections will become evident. 

 When the relations of this ligament have been studied it may be removed. 



Plantar Aponeurosis (O.T. Plantar Fascia). The plantar 

 aponeurosis, which is now brought into view, consists of three 

 portions (a) a medial, (ft) an intermediate, and (c) a lateral 

 part. This subdivision is indicated by a difference in the 

 density of the three parts and by two shallow furrows which 

 traverse the foot in a longitudinal direction, one upon either 

 side of the strong intermediate portion of aponeurosis. Each 

 of the three portions of fascia is in relation to a subjacent 

 muscle. The intermediate portion covers the flexor digitorum 

 brevis ; the lateral part clothes the abductor digiti quinti ; 

 and the medial part covers the abductor hallucis. 



The intermediate portion of the plantar aponeurosis stands 

 out in marked contrast to the lateral and medial portions in 

 point of strength and density. Posteriorly, where it is 

 attached to the medial tuberosity of the calcaneus, it is 

 narrow, but it expands as it passes forwards, and, near the 

 heads of the metatarsal bones, splits into five processes, 

 which are bound together by transverse fibres. In the 

 intervals between the digital slips the metatarsal vessels, the 

 common digital nerves, and the lumbrical muscles appear. 

 Trace the processes forwards. One goes to the root of 

 each toe, and there divides into two slips, which embrace 

 the flexor tendons and become fixed to the flexor sheaths, 

 and to the transverse ligament of the heads of the metatarsal 

 bones on either side of the toe. In its arrangement, there- 

 fore, this portion of the plantar aponeurosis closely resembles 

 the intermediate part of the palmar aponeurosis. 



The lateral and medial parts of the plantar aponeurosis are 

 weak in comparison with the intermediate portion. They 

 simply constitute aponeurotic coverings for the muscles which 

 lie subjacent. A strong band is to be noted in connection 

 with the lateral part. It stretches between the prominence 



