LAMENESS IN THE FORE LEG 69 



humeral region. Great strain is put upon these parts because 

 the biceps brachii is the chief inhibiting structure of the scapu- 

 lohumeral articulation— the one which prevents further flexion 

 of the luimerus during weight bearing. Passing, as it does, over 

 two articulations, the biceps brachii has a somewhat compli- 

 cated function, being a flexor of the radius and an extensor of 

 the humerus. Thus it is seen, the biceps brachii is a weight bear- 

 ing structure, as well as one that has to do with swinging the leg. 

 Etiology and Occurrence. — Because of the exposed position 

 of the bicipital bursa (bursa-intertubercularis) it is occasionally 

 injured. Blows and injuries received in runaway accidents do 

 serious injury to the bursa and because of the peculiar and im- 

 portant part it plays during locomotion, serious injuries are 

 not likely to resolve, and too often chronic lameness results. It 

 is to be noted that the tendon of the biceps brachii (flexor bra- 

 chii) is always involved in cases of inflammation of the bicipital 

 bursa, and according to the late Dr. BelP strain of the biceps 

 brachii is a frequent cause of lameness in city horses, more fre- 

 quent than is generally supposed. 



Pathological Anatomy. — ]\Iore or less destruction of the car- 

 tilaginous portion of the bursa, sometimes involving the tendin- 

 ous portion of the biceps, takes place and, according to MoUer, 

 in some instances there occurs ossification of the tendon. Autop- 

 sies in some old horses reveal the presence of erosions of carti- 

 lage and hyperthrophy of the inflamed parts. 



Symptoms. — In acute inflammations, there is always marked 

 lameness. This is manifested to a greater degree when the sub- 

 ject advances the affected leg. There is incomplete advancement 

 of the member; the toe is dragged when the horse is made to 

 walk and the foot kept in a position posterior to the opposite or 

 weight bearing foot while the suliject is at rest. Lameness is 

 disproportionate to the amount of local manifestation in the way 

 of heat, swelling and pain that is to be recognized on palpation. 

 In fact, in some cases so much pain attends the condition that 

 no weight is borne liy the affected member, and when compelled 

 to walk, the subject hops on the sound leg. 



iDr. Roscoe R. Bell in the Proceedings, N. Y. State Veterinary Medical 

 Society, 1899. 



