no THE SURGICAL ANATOMY OF THE HORSE 



of that of the other side. Later the walls become much hardened and 

 not so compressible. 



It is only when they are sufficiently large to interfere with the action 

 of the joint that lameness results, and in these cases the lameness is 

 mechanical. Such cases, however, are rare, since the arrangement of the 

 anatomical structures here permits a considerable degree of enlargement 

 without the animal experiencing much inconvenience. No pressure is 

 exerted by them on the plantar nerves, since the latter are separated from 

 the swellings by the branches of the suspensory ligament. 



In the treatment of windgalls, Macqueen recommends rest and the 

 application of pressure bandages of linen wrung out of cold water. This 

 is continued for about a fortnight, when the skin over the seat becomes 

 quite cold, and the part is then fired and blistered. 



There is obviously much danger in puncturing a gall. Injections ot 

 iodine have also been used, without, however, any considerable degree of 

 success. 



THE PASTERN JOINT 



This is the first interphalangeal joint, and is formed, therefore, between 

 the distal end of the os sufFraginis and the proximal end of the os corona*. 

 The articular surfaces are described in our chapter on Bones. 



The articular surface of the coronae is amplified by the presence of 

 what is known as the complementary or glenoidal fibro-cartilage. This 

 is attached to the posterior border of the articular surface. Each of its 

 lateral borders is connected with the os suffraginis by three fibrous slips, 

 the most superficial of which is attached anteriorly about midway up the 

 shaft of the suffraginis. The two remaining slips are attached on the 

 lateral aspect of the bone just above its inferior articular surface. To the 

 upper border of the cartilage the superficial inferior sesamoidean ligament 

 is attached, whilst outwardly on either side this ligament is blended with 

 the insertion of the perforatus tendon. 



