160 RESECTION OF THE IvATERAu CARTILAGE 



except the operative area and every precaution taken against 

 the transfer of infecting material from neighboring parts 

 into the wound. 



After the application of the elastic ligature in the meta- 

 carpal or metatarsal region, the groove in the horn is deep- 

 ened with the drawing knife down to the sensitive laminae 

 without injuring them. The groove must be so located 

 that it extends beyond the anterior and posterior borders of 

 the lateral cartilage, and downward to within i or 2 cm. of 

 the margin of the os pedis and approximately perpendicu- 

 lar to the surface of the horn wall so that it will form a 

 secure support for the dressing to be later applied. 



The elevator or long bone chisel is then inserted beneath 

 the lowest part of the semi-circular piece of horn which has 

 been isolated, the horn is elevated from the sensitive struc- 

 tures somewhat, grasped with the heavy forceps and care- 

 fully loosened from the sensitive parts by drawing upward 

 parallelto the laminae until the coronary band is reached. 

 The traction is then directed backward toward the heel, 

 separating the wall from the coronary papillae and kera- 

 phyllous tissue. Care is to be taken here to avoid lacerat- 

 ing the underlying tissues, especially when the traction is 

 first directed backward. If the soft tissues threaten to 

 tear, the danger should be avoided by the timely use of the 

 scalpel or sage knife as conditions may suggest. 



After the coronary band has been smoothed with the 

 scissors, make two perpendicular incisions through the skin 

 and coronary band, one behind the anterior and the other in 

 front of the posterior border of the groove in the horn, and 

 connect the two by means of a semi-circular incision in the 

 sensitive laminae. The U-shaped incision should be so 

 made that between it and the horny wall there is left an 

 area of sensitive laminae i to 2 cm. wide, in order that there 

 may be sufficient room in the soft tissues for the application 

 of the sutures, as shown in Fig. 61. The lines of incision 



