SPRAIN OR STRAIN 299 



renewal of muscular tone and power, strychnine and iron in small 

 repeated doses will also be helpful. 



SPRAIN AND RUPTURE OF THE FLEXOR METATARSI 



The function of this muscle is to flex the canon on the hock and 

 advance the limb. The action displayed by our best movers is for the 

 most part due to its vigorous contractions. Arising from the lower end 

 of the femur or thigh-bone, it terminates below in a number of strong 

 tendinous cords, some of which are inserted into the small bones of the 



Fig. 368. Rupture of the Flexor Metatarsi 



tarsus and others in the upper and front part of the metatarsal or canon 

 bone. 



Sprain to this muscle or its tendon, although not of common occur- 

 rence, is more frequently the cause of lameness behind than is generally 

 allowed, and the writer has observed on several occasions the development 

 of spavin to follow upon sprain to the tendons which insert themselves 

 into the bones of the hock. Whether in these cases the ossific develop- 

 ment was the direct consequence of the sprain cannot be definitely stated. 



The causes which stretch and strain the flexor metatarsi are chiefly 

 those which unduly and forcibly extend the limb, such as violent kicking, 

 slipping backward on to the front of the fetlock while carrying or drawing 

 great weights, severe efforts in withdrawing the feet from deep ground or 



