26: 



Journal of Agriculture . 



[8 May, 1907. 



Spraiq of the Flexor Tendons, 



Sprain of the perforatus tendon occurs in horses " tied in " below the 

 knee and is often spoken of as spraip of the sheath of the tendon. Such 

 a description is only admissible if the perforatus tendon is regarded in the 

 light of a sheath through which the perforans passes. The perforans 

 tendon is the strong, round, corded tendon which ru,ns down posteriorly 

 immediately underneath the skin, and it is this tendon which is most 

 commonly sprained ; especially in horses with long, oblique pasterns, in 

 which by increase of leverage the strain on the tendon is correspondingly 

 greater than in a straight pasterned horse. The seat of the sprain is 

 usually slightly above the fetlock as the tendon passes over the sesamoid 

 groove at the back of the fetlock. A sprain in this situation, when " cal- 

 loused," produces the familiar "bowed tendons" of the race-horse, the 

 steeple-chaser and the hunter. In these animals it is caused bv the sudden 

 strain put upon the tendons when they are extended in the gallop, carrying 

 heavy weights, or when landing over fences. In the latter case at the 



(Alter Hayes.) 



Fig. 6. — Sound 

 back tendons. 

 (After Hayes.) 



' Bowed tendons.' 

 Alter Hayes.) 



moment of contact of the fore feet with the ground the whole weight of 

 both horse and rider is momentarily thrown on the structures at the back 

 of the fetlock. 



Symptoms. — The physical symptoms — heat and swelling — will be 

 obvious in a short time after the sprain is sustained. The attitude when 

 standing and the action during movement closely resemble those presented 

 in the lameness last described — sprain of the inferior check ligament. (See 

 Figs. 5 and 7.) 



Sprain of the Suspensory Ligament. 



This ligament (more definitely described as the " superior suspensory " 

 or "superior sesarnoidean " ligament) is a strong band of fibrous tissue 

 lying in the groove between the two splint bones in contact with the pos- 

 terior surface of the cannon bone and extending from the knee to the fet- 

 lock. It is attached above to the lower row of knee bones and below it 

 bifurcates and becomes attached to the two small bones at the back of the 

 fetlock joint — the sesamoid bones. These branches are continued as 



