40 PERSONAL APPEARANCES IN HEALTH AND DISEASE. 



interlocking and union of the normal parts. But on the 

 other hand there are joints of which the structure admits 

 of ready displacement. When a joint is dislocated, this 

 is shown by the appearance of the end of the displaced 

 bone outside the socket, or separated by an interval from 

 the extremity of the bone with which it was previously 

 in contact. There is then such a deformity as results 

 from the disappearance of the rounded end of the bone 

 at one place, and its appearance at another, a depression 

 occurring where formerly there was a projection. 



There are, however, affections of the joints which are 

 common enough to be frequently observed, and concern- 

 ing which a few words must here be spoken. When 

 from a twist or a strain the ligaments around a joint are 

 injured, i.e., when a sprain, as it is called, takes place, 

 there is always a certain amount of inflammation set up. 

 This may be, and indeed if the sprain be a severe one, is, 

 preceded by considerable bleeding into the soft parts 

 around the joint, and a consequent bruise over the 

 swollen joint is added to the other evidences of injury. 

 The amount of force exerted on the joint, or the direction 

 of the force has not been enough to cause a dislocation, 

 but has sufficed to stretch or rupture ligaments and give 

 rise to the inflammatory changes. A joint may become 

 swollen and inflamed from other forms of injury, as direct 

 blows or wounds. 



