6 THE SURGICAL ANATOMY OF THE HORSE 



Just above the lower edge of the posterior superficial pectoral 

 muscle and in a line with the ridge of the radius, if a little pressure 

 be applied, the posterior radial artery may be located in the living 

 subject by its pulsation, which may be more easily felt if the limb 

 be drawn a little forward. This is a very popular seat for the taking 

 of the pulse. It is also the seat of neurectomy of the median nerve, 

 which will be referred to later. 



Anterior to the ridge of the radius we see the inner aspect of 

 the elevation formed by the extensor metacarpi magnus, to which 

 reference has already been made. In the inferior third of the tore- 

 arm we have the " chesnut," a horny excrescence which upon 

 manipulation will be found to be confined to the skin. The inner 

 surface of the scaphoid and trapezoid, the innermost bones of the two 

 rows of the carpus, should now be felt, and the faint depression 

 between them noted. 



Below the knee the tendons of the perforatus and perforans make 

 their appearance, and may be felt as they are leaving the carpal 

 arch. It is scarcely necessary here to impress the student with the 

 importance of making himself quite familiar with these tendons, 

 particularly where the check ligament joins the perforans, again 

 immediately above the fetlock, and lastly just below this joint, where 

 the perforans is leaving the ring formed by the perforatus, since at 

 these situations the tendons are most commonly sprained. If the knee 

 be flexed and the flexor tendons pushed aside, the suspensory ligament 

 may be felt in the channel formed by the large and small metacarpal 

 bones. 



By the application of pressure with the palmar aspect of the medius 

 finger to the outer or inner side of the most prominent part of the 

 fetlock, the plantar nerve may be rolled beneath the finger about half 

 an inch posteriorly to the middle line. This should be practised, since 

 it is of utility in deciding the seat of plantar neurectomy. The most 

 prominent point at the back ot the fetlock presents another horny 



