DISSECTION OP THE POSTERIOR LIMB. 89 



situated on the inner side of the tarsus. Its fibres are attached above 

 to the tubercle on the inner side of the astragalus ; and, widening as it 

 descends, it becomes inserted into the scaphoid, cuneiform magnum, 

 and large metatarsal bone. 



The Calcaneo-metatarsal or Galcaneo-cuhoid Ligament. — This is a 

 strong, cord-like ligament, situated at the outer side of the back of the 

 hock, and attached to the posterior border of the os calcis, the cuboid, 

 and the head of the external small metatarsal bone. 



The Tarso-metatarsal Ligament will be seen covering the tarsal bones 

 at the back of the hock. It forms a thick mass of fibrous tissue 

 intimately adherent to these bones and to the heads of the metatarsal 

 bones. Its inner border is blended with the lateral ligament of the 

 tibio-tarsal joint; and its outer with the calcaneo-metatarsal ligament. 

 Below it is continued as the subtarsal ligament, which joins the per- 

 forans tendon. The anterior face of the ligament, where not adherent 

 to the bones, is lined by synovial membrane ; and its posterior face is 

 similarly lined by the synovial membrane of the tarsal sheath. 



Birections. — At the front of the hock the point of a scalpel should be 

 introduced into the articulation between the astragalus and the 

 scaphoid ; and by cutting round the hock through the three ligaments 

 just described, an attempt should be made to separate the astragalus 

 and OS calcis, as a single piece, from the rest of the tarsal bones. Before 

 this can be effected, however, there must be cut an interosseous ligament, 

 which is composed of short and strong fibres passing between the os 

 calcis and astragalus on the one hand, and the cuboid and scaphoid on 

 the other. At the same time the synovial membrane belonging to the 

 articulations between these two sets of bones will be opened into. This 

 capsule communicates in front with that of the tibio-tarsal joint, and "is 

 prolonged superiorly between the calcis and astragalus, to lubricate two 

 of the facets by which these bones come into contact. In addition, it 

 descends between the cuboid and scaphoid bones, to form a prolongation 

 for the anterior cuboido-scaphoid arthrodia." — Chauveau. 



Ligaments uniting the Os Calcis and Astragalus. — There are four of 

 these — a superior, two lateral, and an interosseous. The first of these is 

 composed of fibres passing between the two bones above their surfaces 

 of contact ; the lateral ligaments pass between them on each side ; while 

 the interosseous ligament cannot be seen in its entirety, as it passes 

 between the rough impressions on the surfaces of apposition ■ of the 

 bones, and must be cut before these can be separated. 



Directions. — Attention should next be turned to the following liga- 

 ments, which bind together the other four tarsal bones. 



The Anterior Ouhoido-scaphoid Ligament is of small size, and passes 

 between the two bones from which it is named, above the entrance to 

 the canal by which the perforating metatarsal artery passes through the 



