2 THE SURGICAL ANATOMY OF THE HORSE 



upon its conformation in the dropping of the quarter, which becomes 

 particularly apparent when the animal is viewed by the observer 

 standing behind him. In the case of fibrous union the action of the 

 animal is affected to a greater degree, and there is observed a peculiar 

 jerky movement in the region of the fracture, owing to the part to which 

 the muscles are attached having lost its rigidity. 



Passing the hand upwards from the angle of the haunch, a large 

 muscular mass is felt : this is the elevation caused principally by the 

 middle or great gluteus muscle. In well-nourished animals the mass is 

 rounded, but in subjects which are emaciated the surface is somewhat 

 flat. Near the spine another osseous elevation is felt : this is the angle 

 of the croup or internal angle of the ilium. 



Taking a line obliquely downwards and backwards from the angle 

 of the haunch, we feel a hard, upwardly projecting piece of bone which 

 terminates bluntly at its superior extremity : this is the summit of the 

 great femoral trochanter, which is over the hip joint, and its distance 

 from the external angle of the ilium in an animal about fifteen hands high, 

 is thirteen inches. Two inches downwards and forwards from this the 

 convexity of the great trochanter may be felt, but much less distinctly. 

 Careful manipulation will enable the observer to feel a tendon which plays 

 over the outer side of the convexity. This is the tendon of the middle 

 gluteus muscle, which runs to be inserted into the ridge of bone on the 

 outer side of the convexity, and which is called the crest. An imaginary line 

 should now be drawn from the summit of the great trochanter obliquely 

 upwards and backwards to a point seven inches below the root of the tail. 

 The most prominent point here indicates the position of the under- 

 lying tuberosity of the ischium. It is not immediately subcutaneous, 

 but is covered by the semitendinosus muscle. Another imaginary line 

 should be drawn from the summit of the great trochanter, but in this 

 case downwards and forwards to the front of the stifle joint. This 

 indicates the direction of the shaft of the femur, and about one-third of 

 the distance along this line is placed the external or third femoral 



