I 



INTERTARSAL ARTICULATIONS 



353 



is a short, strong fasciculus, passing from the lateral surface of the talus, imme- 

 diately beneath its fibular facet to the lateral surface of the calcaneus. It is placed 

 in front of, but on a deeper plane than, the calcaneofibular ligament, with the fibers 

 of which it is parallel. 



The Medial Talocalcaneal Ligament (ligamentum talocalcaneum mediate; internal 

 calcaneo-astragaloid ligament). The medial talocalcaneal ligament connects the 

 medial tubercle of the back of the talus with the back of the sustentaculum tali. 

 Its fibers blend with those of the plantar calcaneonavicular ligament (Fig. 354) . 



Interosseous ligament of tibio 

 fibular syndesmosis 



Deltoid ligament 

 Tibialis posterior 



flexor digitorum longus 

 Flexor hallucis longus 

 filed, plantar nerve and vessels 

 Quadratus plantce 

 Abductor hallucis 



Lai. plantar nerve and vessels 

 Flexor digitorum brevis 



/ Interosseous talocalcaneal 



Peronceus longus 

 Abductor digiti quinti 



FIG. 357. Coronal section through right talocrural and talocalcaneal joints. 



The Interosseous Talocalcaneal Ligament (ligamentum talocalcaneum interosseum) 

 (Figs. 357, 359). The interosseous talocalcaneal ligament forms the chief bond 

 of union between the bones. It is, in fact, a portion of the united capsules of the 

 talocalcaneonavicular and the talocalcaneal joints, and consists of two partially 

 united layers of fibers, one belonging to the former and the other to the latter joint. 

 It is attached, above, to the groove between the articular facets of the under surface 

 of the talus; below, to a corresponding depression on the upper surface of the cal- 

 caneus.' It is very thick and strong, being at least 2.5 cm. in breadth from side 

 to side, and serves to bind the calcaneus and talus firmly together. 



Synovial Membrane (Fig. 360). The synovial membrane lines the capsule of the joint, and 

 is distinct from the other synovial membranes of the tarsus. 



Movements. The movements permitted between the talus and calcaneus are limited to glid- 

 ing of the one bone on the other backward and forward and from side to side. 



Talocalcaneonavicular Articulation (articulatio talocalcaneonavicularis) . This 



articulation is an arthrodial joint: the rounded head of the talus being received 



into the concavity formed by the posterior surface of the navicular, the anterior 



articular surface of the calcaneus, and the upper surface of the plantar calcaneo- 



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