LAMENESS IN HORSES. 
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sical force) inextensible, they, themselves, can neither be stretched 
nor strained, so long as they maintain their cohesion of substance. 
To discover in what part the sprain or lesion is likely to be 
situate, it will be advisable to submit the leg in its normal state 
to anatomical examination. 
If we strip or dissect off the skin from the flexor tendons, we 
find, underneath, between them and the skin, a quantity of loose 
cellular tissue ; cutting away which we come to a close or proper 
tunic of the same substance immediately enveloping the tendons. 
This under or proper covering, however, is fibrous as well as cel- 
lular in composition. For the space of a hand’s breadth below 
the knee the glistening (tendinous) fibres may be seen crossing 
obliquely over the tendons, as they run from the annular ligament 
of the knee to be implanted into the external border of the cannon 
bone, behind the external splint bone. This forms the sheath of 
the tendons. And when we slit it open, we discover a cavity 
possessing a surface of a synovial nature ; and that a sac or bursa 
is thereby formed, which extends half way down the leg, and is 
there closed. Through the bursa runs the perforans tendon, which 
may indeed be said to form a posterior boundary to it. The in- 
terval between the flexor tendons and the suspensory ligament, 
in their front, is likewise filled with inter-uniting cellular sub- 
stance. This brief and imperfect anatomical sketch may serve to 
illustrate the 
Nature of Sprain. It will at once shew, that, although the 
tendons themselves are incapable of extension, and are too firm 
and strong in their texture to sustain hurt from any common acci- 
dent, yet are surrounded, and connected together, and to the parts 
contiguous to them, by a soft delicate tissue which must, every 
time they are forcibly pulled or stretched, be extremely liable to 
strain and laceration ; and this, in fact, it is, which in all ordinary 
cases, constitutes the true and sole nature of “ sprain of the back 
sinews.” Coleman defined such a sprain to be “ an inflammation 
of the cellular tissue connecting the perforatus and perforans ten- 
dons together;” and this was taking a fair general view of its 
nature. To enter into particulars, we shall first have to notice the 
puffy swelling or knot, mentioned before, as being discoverable in 
the course of the tendons, about the middle of the leg ; the patho- 
logy of which is, that effusion of fluid has taken place into the 
sac or bursal cavity but lately described as existing within the 
sheath of the flexor tendons: the effusion being, as it would 
appear, different at one stage — or, rather, under one form of dis- 
ease — from what it is under another. Suppose, for example, the 
swelling, as it does in some severe forms of sprain, immediately 
follows the accident ; we cannot, in this case, imagine it can con- 
