122 



THE ABTICI7LATI0N8. 



lation IS, therefore, essentially constituted by two opposite osseous surfaces, 

 which are moulded to each other. These are either contiguous, independent, 

 and very movable — continuous with each other by means of a cartilaginous 

 substance which condemns them, if not to total immobility, at least to very 



Fig. 75. 



PLANS OF THE DirFEKENT GLASSES OP AETICTJLATIONS. 



A, Suture. — 1, Periosteum ; 2, Sutural ligament, — B, Ampliiarthrosis ; a. First 

 degree.— 1, Periosteum ; 2, Articular cartilage •, 3, Interarticular ligament.— 6, 

 Second degree ; 4, Single cavity in the interarticular ligament. — c, Third degree ; 

 5, Double cavity in the interarticular ligament. — c, Diarthrosis ; 6, Simple 

 diartUrosis. — 1, Periosteum; 2, Articular cartilage; 3, Epithelial layer of the 

 synovial membrane — dotted line ; 4, Fibrous capsule ; 5, Cul-de-sac of the syno- 

 vial membrane ; 6, Fibrous layer of the synovial membrane. — c, Double diarthrosis • 

 7, Interarticular meniscus ; 8, 9, Cavities of the two synovial membranes. 



limited movements : or united by a iibro-cartilage whose elasticity permits a 

 certain degree of displacement between the bones which are in contact. 



In the first case, the articulations are classed as diarthroses, or movable 

 articulations. 



In the second, they are designated synarthroses, sutures, or immovable 

 articulations. 



