72 DISEASES OF MUSCLES AND TENDONS. 



at the point where it passes over the trochanter, there is nothing to be 

 done. Eeduction will occur spontaneously, and entire liberty of action 

 will be regained. Cruzel states that it is sometimes sufficient to force 

 the animal to move down a slope, in order to withdraw the trochanter 

 from the depression in which it has been lodged, and to restore its 

 normal mobilit}-. 



Eest and good feeding favour the deposition of fat, and soon alter 

 the conditions responsible for the accident ; the muscles of the quarter 

 become surrounded with fat, the external ischio-tibial muscle (biceps 

 femoris) is thrust outwards on account of its superficial position, and 

 then cannot be ruptured by the summit of the trochanter. If, on the 

 other hand, the musculo-aponeurotic layer is fissured and the summit of 

 the trochanter firmly fixed in the opening, oj^eration becomes necessary. 

 This consists in incising the anterior margin of the muscle over the 

 afore-mentioned rigid cord. The margins of the wound retract, the 

 tension of the cord is diminished, the trochanter released, and the 

 normal play of the limb restored. 



Numerous methods of operation have been described and a numl)er 

 of special instruments invented. The earlier methods consisted in simple 

 sul)cutaneous section of the rigid cord formed by the musculo-aponeurotic 

 layer and the muscle. Subcutaneous section is carried out exactly like 

 tenotomy, using straight and curved tenotomes. The seat of operation 

 is about three inches below the summit of the trochanter. In the 

 absence of tenotomes, section may be performed with a bistoury intro- 

 duced from below the muscle by means of a grooved director, which has 

 been inserted through a cutaneous puncture made at the point indicated 

 over the anterior margin of the prominent cord. 



In better nourished subjects, in which this cord is less prominent, 

 the operator may, to ensure greater accuracy, make a vertical incision 

 an inch or two in length at the point selected over the anterior margin 

 of the muscle, isolate this muscle by means of the director; and after- 

 wards perform the section. Considerable hfemorrhage occasionally 

 follows division of some small muscular vessel, but is of no consequence 

 unless the wound has been infected. 



RUPTURE OF THE FLEXOR METATARSI. 



The rupture of this tendon-muscle is exceptional, and, according to the 

 description given by Furlanetto, is attended by the same symptoms as in 

 the horse — i.e., flexion of the stifle joint is not accompanied by flexion of 

 the hock or of the metatarsus on the til)ia. The cannon-bone hangs 

 vertically when the liml) is moved. 



Eecovery follows prolonged rest. 



