Chap, xiii.] REGION OF ELBOW. 223 



upwards by that muscle, the biceps, and the brachialis 

 anticus. The median, or ulnar nerves, especially the 

 latter, may be severely damaged. 



2. The " T-shaped fracture " is but a variety of the 

 lesion just noted. In addition to the transverse 

 fracture above the condyles, there is also a vertical 

 fracture running between the two condyles into the 

 joint. The lower fragment is thus divided into two 

 parts. The displacement is the same. The fracture 

 is very usually due to a fall upon the bent elbow, and 

 here possibly also the tip of the olecranon acts as 

 a wedge, producing the transverse fracture, while the 

 prominent ridge along the middle of the greater 

 sigmoid cavity, acting as a second wedge, produces 

 the vertical fracture into the joint. 



3, 4, and 5, For surgical purposes it is well to 

 limit the term " condyle " to such parts of the 

 extremity of the humerus as are within the capsule, 

 and the term " epicondyle " to such parts of the lower 

 projections of the bone as are without the joint. 



In the so-called fracture of the inner condyle 

 the line of separation generally commences about half 

 an inch above the tip of the epicondyle (and, therefore, 

 outside the joint), and running obliquely outwards 

 through the olecranon and coronoid fossae, enters the 

 articulation through the centre of the trochlear surface 

 (Hamilton). The fragment is often displaced a little 

 upwards, backwards, and inwards, the ulna going 

 with it. 



In the fracture of the external condyle the line 

 commences also above the epicondyle and outside 

 the joint, and running downwards enters the joint 

 usually between the trochlear surface and the surface 

 for the radius. The displacement is trifling and 

 inconstant. 



On account of its insignificant size, a fracture 

 of the external epicondyle is scarcely possible. 



