358 
LAMENESS IN HORSES. 
secure retreat in a part so concealed from view and touch as the 
shoulder-joint. The shoulder of the quadruped includes pretty 
well a fourth part of his body ; it occupies a large space, compre- 
hends many and various parts, and is complicated altogether in its 
structure. The bulk of it is made up of muscles. There are but 
two bones entering into its composition — the scapula and os humeri; 
but the joint they form between them, of the ball-and-socket cha- 
racter, possesses greater variety of motion than any other joint in 
the limbs ; and, moreover, has connected with it a pulley-like 
bursal cavity, containing synovia the same as the main joint, which, 
there exist strong reasons for believing is, if not the ordinary, at 
least a very frequent seat of shoulder lameness. The tendon of 
the flexor brachii — a muscle principally concerned in the flexion 
of the arm of the quadruped — passes down from its attachment to 
the scapula within a groove formed between the tubercles upon the 
head of the os humeri , and plays up and down within this groove 
after the manner of a rope over a pulley ; the surfaces both of ten- 
don and groove being coated with articular cartilage and enclosed 
within a synovial sac. Now, from the circumstances of this muscle 
being mainly employed in bending or raising the arm, of the known 
liability of bursal joints, such as this, to get out of order, and of 
the presumed and pretty well ascertained seat of ailment being the 
point of the shoulder — a part directly opposite to this bursa — there 
seem good reasons for believing that this said bursa is the especial 
or usual seat of derangement or disease in shoulder lameness. It 
may appear strange, or even inexcusable, that in this, the sixtieth 
year, or thereabouts, of the introduction of veterinary science 
among us, we should be found making use of language so dubious 
as this in regard to the site and pathology of the lameness in 
question. It must be borne in mind, however, that for one case 
that is in verity shoulder lameness there occur thirty that are not ; 
and that, being a lameness that is commonly curable, or one of 
which horses, give them time, somehow or other are found to 
recover, or, at all events, one which they never die of, or are put 
to death for, we get, in point of fact, little or no opportunity of exa- 
mining into the state of parts supposed to be diseased ; though, we 
may add, that such facts — and they are mostly of foreign growth 
— as stand on record shew the shoulder-joint, if not the bursa , to 
be the seat of disease. 
The French veterinarians call shoulder lameness ecart , 
because they say it has the effect of causing the horse “ tcarter le 
membre du thorax.” And Barthelemy — one of their best authori- 
ties — asserts that the scapulo-humeral articulation, with its capsu- 
lar ligament and investing muscles and tendons, is the seat of 
the lameness. 
