274 A MANUAL OF ANATOMY 



The Foot as a Whole. 



The foot presents two surfaces — •dorsal and plantar — two borders 

 — inner and outer — and two extremities — anterior and posterior. 



The dorsal or superior surface is arched, both longitudinally and 

 transversely, and the superior surface of the astragalus constitutes 

 its summit. The astragalus is the only bone of the tarsus which 

 articulates with the tibia and fibula. 



The plantar surface is concave, both longitudinally and trans- 

 versely, in conformity with the longitudinal and transverse arches. 

 When an articulated foot is placed upon a table, with the plantar 

 surface downwards, the parts in contact with the table are as 

 follows: Posteriorly, the internal and external tubercles on the 

 plantar aspect of the tuber calcis, and anteriorly the heads of the 

 metatarsal bones. 



The plantar surface presents important projections and grooves, 

 which will be enumerated, as nearly as possible, in order from 

 behind forwards. 



1. The internal and external tubercles on the plantar aspect of 

 the tuber calcis. 



The internal tubercle gives attachment to the following struc- 

 tures : 



(i) Internal division of plantar fascia (part of). 



(2) Central division of plantar fascia. 



(3) Outer head of abductor hallucis (part of). 



(4) Flexor brevis digitorum (part of). 



(5) Abductor minimi digiti (part of); 



The external tubercle gives attachment to the following struc- 

 tures : 



(i) Outer division of plantar fascia. 

 (2) Abductor minimi digiti (part of). 



2. The anterior tubercle of the os calcis, which gives attachment 

 to the short plantar ligament. 



3. The sustentaculum tali of the os calcis, close to the inner border i 

 of the foot, which is grooved inferiorly for the tendon of the flexor 

 longus hallucis, the groove being continuous with that on the pos- 

 terior border of the astragalus. Anteriorly, the sustentaculum talij 

 gives attachment to the inferior calcaneo-navicular or spring liga-| 

 ment. 



4. The tuberosity of the scaphoid or navicular hone, close to the 

 inner border of the foot, which gives insertion to the principn' 

 portion of the tendon of the tibiahs posticus. 



5. The spring tubercle on the plantar surface of the naviculai 

 hone, for the spring hgament. 



6. The eminence on the plantar surface of the internal cuneifori' 

 hone, close to the inner border of the foot, for a slip of the tendo. 

 of the tibialis posticus. 



