LIGAMENTARY SYSTEM. 



291 



Capsular ligament envelopes the articula- 

 tory surfaces, and is inserted beyond their 

 limits ; in front it is united with the exten- 

 sor tendon ; behind, it is sti'engthened by 

 the tendo perforans. In addition to the 

 capsular, there are three pairs of ligaments. 



Tlie first pair passes from the superior 

 edges of the os pedis to the lateral parts of 

 the OS corona, and are inserted about its 

 middle. 



The second pair is stretched from the ex- 

 tremities of the OS pedis to the os corona, 

 and are fixed below and behind the first. 



Third pair arise from the sides of the 

 coronal process, and terminate in the car- 

 tilages. 



The ligaments of the os naviculare are 

 four, viz. : two single, and one pair. 



Superior ligament runs from its upper 

 and posterior part to the tendo-perforans. 



Inferior is a very broad ligament, arising 

 from the whole of the lower edge of the 

 bone, and thence extending to the os pedis, 

 above the long extensor tendon. 



Lateral ligaments fix the os naviculare, 

 by its two ends, to the sides of the os 

 corona. 



ARTICULATIONS OF THE HIND EXTREMITY. 



The thigh joint is formed by the reception 

 of the head of the os femoris into its socket. 



Capsular ligament is attached around the 

 cervix of the os femoris and the margin of 

 the acetabulum ; it is thickly clothed on 

 every side by muscle, which assists to main- 

 tain its position. 



The acetabulum is surrounded by the 

 circular ligament, whose border turns in- 

 ward to embrace the cartilaginous head of 

 the OS femoris. 



The notch in this cavity, to its inward 

 side, is crossed by the transverse ligament, 

 which here makes up for the deficiency in 

 the bone. 



Ligamentum teres consists of a bundle of 

 ligamentous fibres inclosed in a sheath, 

 which proceed from a pit in the inner and 

 upper part of the ball to a similar one in 

 the roof of the socket. Another portion of 

 it leaves the cavity under the transverse 

 ligament, and is implanted in the pubes. 



The synovial membrane lines the socket, 

 and is reflected over these parts. 



Stifie joint is composed of the os femoris, 

 the tibia, and patella. 



Ligamenta patella are composed of four 

 strong cords, which descend over the con- 

 dyles of the OS femoris, and are inserted 

 into the tubercle of the tibia. The external 

 one passes upon the outer and anterior 

 part of the external condyle ; the internal, 

 upon the inward part of the internal con- 

 dyle ; and the middle one, between them. 

 They approach each other in their descent. 

 Concealed by the external one is the fourth 

 ligament of the pateUa ; it runs to the out- 

 ward part of the tibia. 



The patella, with its articulatory surface 

 of the condyles in front, forms a joint of its 

 own, perfectly distinct from that between 

 the tibia and os femoris. 



Its capsular ligament is fixed to its sur- 

 rounding border. 



Internal lateral ligament descends from 

 the internal condyle to the inner and upper 

 part of the tibia. 



External lateral ligament — stronger than 

 the internal — runs from the external con- 

 dyle to the upper end of the fibula. 



Crucial ligaments, short and strong, and 

 deeply buried within the joint, run from the 

 space within the condyles to. the tibia. 



The synovial membrane, after having 

 lined the capsule, is reflected upon the car- 

 tilages and ligaments included within it. 



Hock joint has four lateral ligaments, 

 two on each side, called internal and exter- 

 nal. 



Capsular ligament includes the lower end 

 of the tibia, and the pully-lilvc part of the 

 astragulus; to both of which, and the lat- 

 eral ligaments, and to the os calcis, it is 

 firmly attached. 



The OS calcis forms a joint with the os 

 cuboides, and the ossa cuneiforme are also 

 a joint, and the middle and small bones 

 make joints with the cuboid above, and the 

 metatarsi below ; hence, there are six artic- 

 ulations in addition to what we commonly 

 understand by the hock joint, that between 

 the tibia and astragulus. 



