THE KNEE. 241 



connexion between the individual bones, there is a perfect capsular h'tra- 

 nient here, extendinj^ from the bone of the arm to those of the leg ; 

 and the result of the whole is, that, although the centre of such a column 

 must be the weakest part, and most liable to bow out and give way, the 

 hardest work and the severest accidents produce little deformity, and no 

 dislocation in the knee: nor do the shocks and jars of many a year cause 

 inflammation or disease. It is an undeniable fact, that such is the perfect 

 construction of this joint, and to so great a deg-ree does it lessen concus- 

 sion, that the injuries resulting from hard work are, almost without an 

 exception, found below the knee. 



The seventh bone, the trapezium, so called from its quadrangular figure, 

 is placed (see M, p. 63) behind the others, and does not bear the 

 slightest portion of the weight. It, however, is very useful. Two of the 

 flexor muscles, already described, proceeding from the bone of the arm, 

 are inserted into it ; and thus, being thrown off the limb, have a less oblique 

 direction given to them ; and, therefore, according to the principle of the 

 lever, act with considerably more power. It is also useful in another way. 

 As the tendons of the various muscles descend the limbs, they are tied 

 down, as we have described, by strong ligamentous bands : this is particu- 

 larly the case in the neighbourhood of the joints. The use of this is 

 evident. The extensor tendons, which lie principally on the front of the 

 leg, are prevented from starting, and strengthened and assisted in their 

 action ; but the flexor tendons which lie at the back would be liable to 

 friction, and their motion would be impeded, if they were bound down too 

 tightly. This projecting bone prevents the annular or ring-like ligament 

 from pressing too closely on the main flexor tendons of the foot; and while 

 it leaves them room to play, leaves room likewise for a little bag, filled with 

 mucus to surround them, which mucus, oozing slowly out, supplies the 

 whole course af the tendons down the legs with a fluid that takes away 

 the possibiiity of injurious friction. 



The knee should be broad. It should present a very striking width, 

 compared with the arm above, or the shank below. The broader the 

 knee is, the more space there is for the attachment of muscles, and for the 

 accumulation of ligamentous expansions and bands. In proportion to the 

 breadth of the knee there will be more strength; and likewise the direction of 

 some muscles will be less oblique, and those of others will be more removed 

 from the centre of motion ; and, in either case, much power will be gained. 



BROKEN KNEES. 



The treatment of broken knees is a subject of considerable importance, for 

 many horses are sadly blemished, and others are destroyed, by wounds in 

 the knee-joint. The horse, when falling, naturally throws his knees for- 

 ward ; they receive all his weight, and are sometimes very extensively 

 lacerated. The first thing to be done is, by very careful washing with 

 warm water, to cleanse the wound from all gravel and dirt. It must then 

 be ascertained whether the joint is penetrated. The grating of the probe 

 on one of the bones of the knee, on the depth to which the probe enters 

 the wound, will ol\en too plainly indicate that the joint has been opened. 

 Should any doubt exist, let a linseed-meal poultice be applied. This will 

 at least act as a fomentation to the wound, and will prevent or abate 

 inflammation ; and when, twelve hours afterwards, it is taken off, the 

 synovia, or joint-oil, in the form of a glairy, yellowish, transparent fluid, will 

 be seen, if the capsular ligament has been ][;enetrated. Should doubt remain 

 alter the first poultice, apply a second. 



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