(To Fig. 86, former page.) 



The lateral ligaments are very important in relation to the movements of 

 the joint. They become tense in marked flexion and extension. 



Synovial continuations corresponding to the 3 fossae (vide supra) are 

 formed by the wall of the Capsule: a large posterior, and 2 smaller anterior con- 

 tinuations. The one first mentioned is drawn upwards and backwards, during 

 extension, thus coming to lie above the Olecranon, between this bone and the 

 Triceps (cf . figure). During flexion, it fills the Olecranon Fossa ; — the 2 anterior 

 processes present an opposite movement; thus the Anterior Ulnar Synovial Con- 

 tinuation (cf. figure) lies in the greater anterior fossa in front of the Trochlea of 

 the Humerus, during extension. 



During extension a recess of the Capsule — analogous to the one above 

 the Patella in the knee-joint — is formed above and behind the Olecranon. 

 This cul-de-sac extends higher in the living subject than is shewn in our figure, 

 which, necessarily, was drawn after death. 



The Joint is most readily accessible from behind: in front there are 

 powerful muscles, and large vessels and nerves to be avoided, behind there is 

 onl}' the Ulnar Nerve. Effusion into the joint bulges most at either side of the 

 Olecranon. 



Fig. 87 and 88. Relation of the Capsule of the Elbow-Joint to the 

 Epiphysial Lines. (After voN Brunn.) 



Fig. 87. Frontal Section through the Right Elbow-Joint of a 



person aged 19 years. 



View from behind. 



The Joint-Cavit}' extends far beyond the Epiphysial Line of the Head of 

 the Radius; but even here, the Capsule arises (cf. Shoulder-Joint) from the Arti- 

 cular Cartilage, and is loosely attached to the Radius as far as the lower end of 

 the cavity. 



Disconnection of the united Epiphyses of the External Condyle and the 

 Radial Head of the Humerus from the rest of the bone will involve the Joint- 

 Cavity; the latter would also be affected if the Epiphysis of the Trochlea were 

 separated at the place where the Trochlea and the Radial Head meet. 



Fig. 88. Sagittal Section through the Left Elbo^v-Joint of a child 



aged 8 years. 



View from the inner side. 



The boundary line between the Diaphysis of the Ulna and the Epiphysis 

 of the Olecranon passes across the Joint-Cartilage. — The Capsule also extends 

 above the line of the Diaphysis of the Humerus: Though fairly strong in front 

 and readily removed as far as the Joint-Cartilage it is firmly attached to the 

 Olecranon Fossa, and very thin, thus defying dissection. 



Separation of the Epiphyses, — both of Humerus and Ulna — , will there- 

 fore affect the Joint-Cavity. 



