Joints of the Lower Extremity. 



217 



Tibia - 



Fibula 



Trochlea tali 



Ligamentum 

 talotibiale posterius 



Ligamentum 

 calcaneotibiale 

 Ligamentum 

 talocalcaneum mediale 



Sulcus in. flexoris hallucis longi 



Ligamentum malleoli 

 lateralis posterius 



Ligamentum talo- 

 fibulare posterius 



Ligamentum talo- 

 calcaneum posterius 



Ligamentum 

 calcaneofibulare 



Tuber calcanei 



263. Joints of the right foot, articulationes pedis, from behind. 



(The capsulae articulares have been removed except for the strengthening ligaments.) 



Syndesmosis tiMoftbularis (continued). The ligamentum malleoli lateralis poste- 

 rius has a broad origin from the region behind the incisura fibularis tibiae and from the 

 posterior margin of the facies articularis inferior tibiae and goes obliquely downward to the 

 posterior surface of the malleolus lateralis; its lower fibres help to enlarge and deepen the 

 jomt cavity for the trochlea tali. 



In the formation of the articulatio talocruralis (ankle-joint) (see also Figs. 264 and 

 265) the trochlea tali moves in the joint cavity formed by the distal end-pieces of the tibia 

 and fibula; here the facies superior tali glides upon the facies articularis inferior tibiae, the 

 facies malleolaris lateralis tali upon the facies articularis malleoli fibulae and the facies malleo- 

 laris medialis tali upon the facies articularis malleolaris tibiae ; the two malleoli thus embrace 

 the trochlea tali from two sides. The capsula articularis arises everywhere close to the margin 

 of the cartilaginous surfaces : only in front of the facies articularis superior tali does it cover 

 also a part of the collum tali which is free from cartilage; at the sides the capsule is tight; 

 in front and behind it is looser. Very powerful strengthening ligaments, lateral as ligamenta 

 talofibularia et calcaneofibulare (see p. 218), medial as ligamentum deltoideum (see p. 219), 

 go from the two malleoli to the ankle bones. 



