710 OPERATIONS ON THE FOOT. 



must involve the whole thickness of the skin, as far as the ten- 

 dons, and should be made in the middle of the coronet region, as 

 near the foot as possible. It gives rise to an abimdant hemor- 

 rhage, which relieves the part, and warm poultices and baths, to 

 accelerate the suppuration, are then indicated. 



When the product of suppuration has passed in the tendinous 

 sheath, a longitudinal opening of this part towards the most de- 

 pendent points, is indicated. To do this, a canulated directory is 

 introduced to guide the bistoury ; when the incision is made, the 

 pus flows freely, and by this mode the large blood vessels and the 

 various ligaments of the region are avoided in the operation. 



Notwithstanding the incision, or if the suppuration had already 

 accumulated before it was made, the pus may also accumulate in 

 the pouch formed by the tendinous sheath behind the tendons. It 

 is then very difficult to prevent its collection in those deep joarts, 

 and it may extend to the small sesamoid. It is because the pus 

 cannot run toward the skin that it filtrates along the tendon. It 

 is only by pressure and by injections that the indications presented 

 can be fulfilled. After making free incisions, one may try by pres- 

 sure to remove the pus accumulated between the tendons and their 

 sheaths, following it by cleansing injections, which must be re- 

 peated as often as possible. 



The wounds which remain after the slough, in the superficial 

 tendinous quittor, and that which follows the opening of the 

 simple or multiple abscesses when it is deeper, are always charac- 

 terized by the presence of fistulas running down to some necrotic 

 spot of the tendons or of their sheaths. For these, an injection 

 is recommended of tincture of aloes, tincture of iodine, and some- 

 times of Villate's solution; lately, dressings with petroleum or 

 phenic acid have been used. Phenicated baths, those of sulphate 

 of iron and lotions of permanganate of potash have also proved 

 useful. At times, when the fistulas are persistent, it is necessary, 

 after enlarging them, to have recourse to actual cauterization -with 

 a pointed cautery introduced, while at a white heat, down to the 

 bottom of the tract. A general dressing of the wound follows, 

 with tincture of aloes, sometimes with egyptiacum. The di*ess- 

 ings should be more or less frequent, according to the quantity of 

 the pus discharged. We must dress it until the wound is entirely 

 healed, and it must, moreover, be carefully watched for fear of 

 another infiltration of pus, or the formation of other fistulas. 



