DEOPPED ELBOW. 311 



but only reminds the animal that he must not practise it on the 

 side which was injured. Figs. 123, 124, 125, and 126, which are 

 reproductions of photographs I took from specimens very kindly 

 lent to me by Mr. Willis, show these fractures. Increased thickness 

 of bone due to fracture, is well marked in these illustrations. 



Occasionally, saddle horses meet with this accident from falls 

 and other injuries. 



SYMPTOMS. — Sudden lameness with more or less paralysis of 

 the limb ; and " dropped elbow,'' in which case the elbow of the 

 affected leg is held about six inches lower than its fellow, with the 

 knee and fetlock bent, and the heel raised. The toe generally 

 rests on the ground a little behind the toe of the sound leg. The 

 lameness is characterised by inability to raise the foot, although 

 the limb can be drawn forward to a greater or less extent; and 

 by circumduction (outward rotation of tlie foot, during forward 

 movement). This peculiarity of gait is caused by the fact that 

 any contraction of the muscles whose office is to keep the limb 

 close to the side of the animal (the adductor muscles), would 

 give rise to pain by setting up movement in the broken surfaces 

 of bone ; and that the muscle (the levator humeri) whioli draws 

 the limb forward, has very little disturbing influence on the seat 

 of injury. This muscle is attached at one end to the humerus 

 (the bone which lies between the elbow and the point of the 

 shoulder), and at the other, to the top of the head. As a rule the 

 condition of dropped elbow lasts five or six weeks, and the lame- 

 ness gradually passes off in a few weeks longer. Owing to disuse, 

 there is some wasting of the flexor hrachii muscle (pp. 58 to 60), 

 which recovers its normal state after a time. 



Recognition of crepitus is a reliable method for distinguishing 

 fracture of the first rib from other injuries (for instance, sprain 

 of the flexor brachii, fracture of the scapula, fracture of the 

 trapezium bone, and fracture of the navicular bone) which present 

 the symptoms of " dropped elbow." Crepitus of a fractured first 

 rib can be obtained only by crossing the fore leg near the affected 

 rib as far as possible across the front of the sternum, and then 

 jerking it outwards (adduction and abduction). The crepitus thus 

 obtained will be readily felt when the hand during the. process is 

 kept firmly on the scapula, but at the same time the crepitus, 

 though distinct, will be dull, and, of course, cannot be localised 

 to any part of the scapula. It will also be absent when the leg is 

 moved backwards and forwards. 



In all cases of " dropped elbow," there is the possibility of 

 sprain of the shoulder (p. 58). 



The only rational TREATMENT is rest. 



