Clear the bone in front and behind with the handle of the scalpel, and strongly evert the foot when the tibia and upper surface of the astragalus will be exposed at the internal wound.

The bone can now be divided from behind forward, by a narrow-bladed saw being passed through the internal wound, behind the tibia, and made to appear at the external opening. The upper surface of the astragalus may be now sawn off.

The wound must be thoroughly washed out with bichloride solution, a drainage tube passed through from one side of the joint to the other, the sides of the incision closed by interrupted sutures, and the whole dressed antiseptically.

The foot and leg must be covered with a bandage and plaster rollers applied; care being taken to give the foot a proper angle with the leg, the foot being held by the hand of an assistant until the plaster is hardened. Traps are to be cut on the sides of the splint opposite the wounds.

Erichsen, in his work on the "Science and Art of Surgery," lays down the following general rules for the performance of resections of joints in cases in which it is admissible :

I. As a substitute for amputation in cases in which the joint is so extensively diseased that the patient will be worn out by the discharge or pain, unless it be removed.

2. In some cases of articular disease in which amputation would not be justifiable, excision may be done in order to hasten the cure, and this saves years of suffering to the patient.

3. Excision may be done in cases in which amputation is not practicable, as in some cases of disease of the hip-joint, or of the temporo-maxillary articulation.

4. As a substitute for other and less efficient treatment; in order to restore the utility of a limb to a joint; as in osseous ankylosis of the elbow, or in faulty ankylosis of the knee.

5. Excision may be required, in bad compound dislocations and fractures into joints, especially in gunshot injuries, more particularly in those of the head of the humerus, and of the bones entering into the elbow joint.

As a general rule, excisions are required only in those cases in which the articular ends of the bones are diseased either primarily or secondarily. Conditions of Success.-For resection to succeed, the following conditions appear to be necessary :

:

I. The disease should not be too extensive, so that its removal would entail such an amount of mutilation of the limb as to render it ess useful

deeply between the pronator ed by the last named; in its of the supinator longus and by venæ comites, and in the the forearm must be held in alf to three inches long, must gh, and the muscles separated comites, the ligature needle is

of the wrist, an incision is to be yloid process of the radius to the

The guide to the artery is the crosses the artery before it dips 1 on the ulnar side of the tendon. the arm is covered by the four nner condyle; in the lower half he flexor digitorum sublimis and accompanied by two veins. The ; it then crosses in front of the the limb, lying on the ulnar side

third of its course, a longitudinal about two inches below the inner of the width of the arm from the three inches. The division between possible, between the tendons and would be looked for as a guide to the ed from the nerves.

he wrist requires an incision two inches dge of the limb; the incision should Inaris. After the skin and fascia have ad covered by the tendon of the flexor nd the tendon of the flexor digitorum ould be passed from within outward, to to the inner side of the artery; the vena

lies on the inner border of the psoas er side and below. The genital branch n it for a short distance. The artery is inigh up is crossed by the sigmoid flexure of

the colon on the left side, and by the ilium on the right side; the ureter is near its division. Low down it is crossed by the spermatic cord in the male and the round ligament in the female, and is crossed by the circumflex iliac vein.

To tie the external iliac the patient must be placed flat on a table, so that the abdominal muscles may be rendered tense. Make an incision, three and a half or four inches long, above and parallel to Poupart's ligament, beginning about half an inch outside the external abdominal ring; carry it through the skin and superficial fascia, and lay bare the external oblique tendon. The cut through this tendon, the internal oblique and trans

ARTERIES.

versalis muscles, to the extent of the incision. A portion of the muscular fibres should be lifted with the forceps and carefully cut through, to form an opening into which a broad, flat, grooved director must be insinuated, and the muscle divided upon it to the necessary extent. Now gently draw the edges of the wound asunder with bent spatula; the opening must be enlarged by tearing with the fingers. Then carefully strip the peritoneum off from the iliac fossa until the finger reaches the artery. The sheath must be scratched through with forceps and director at the point selected, and the artery separated from the vein; the aneurism needle is then passed

between them, excluding the genito-crural nerve. The wound must be brought together by sutures, and the trunk bent forward, to relax the muscles.

The Common Iliac Artery.-To tie this artery make a slightly curved incision, six inches in length, the lower third being about two inches above Poupart's ligament and parallel with it. Divide the muscles and tear through the transversalis fascia; gently repress the intestines upward, which will protrude through the wound, and separate the peritoneum from the iliac fossa. When the brim of the pelvis is reached, seek the external iliac, which is a guide to the common trunk. Open the sheath just above the bifurcation, and, if possible, pass the needle from within outward.

FIG 76.

The Femoral Artery.-To tie the femoral artery in its upper division, first ascertain its course, which is indicated by a line drawn from the middle of Poupart's ligament to the inner femoral condyle, when the knee is bent and the thigh turned outward; an incision, three or four inches in length, must be made over it, about two or three inches below Poupart's ligament. Divide the fat and superficial fascia; the saphena vein lies on the inside of the incision. Then divide the fascia lata to the same extent as the skin. Draw the sartorius gently out. ward, which will expose the sheath of the artery; open it sufficiently to admit the needle, being careful not to transfix the vein; to avoid this use a blunt needle; pass it from the inner side.

To tie the femoral artery in the lower part of its course in Hunter's canal. Turn the limb a little outward, bend the knee and raise the leg on a pillow; make an incision three inches long, in a line drawn from the middle of Poupart's ligament to the inner condyle, the upper half in the middle third, and extending down into the lower third of the thigh; cut through the integument and take care to avoid the saphena vein. Divide the deep fascia, expose the sartorius and the tendinous

ARTERY.

aponeurosis which passes under it. With a retractor have the edge of the muscle held outward. Lift up a portion of the aponeurotic sheath with forceps and divide it. Introduce a director and divide the sheath upon it; the artery will be found with the vein behind, and a little to the outer side. Pass the ligature from without inward.

FIG. 77.

TYING THE POSTERIOR TIBIAL ARTERY.

To tie the Popliteal Artery, the patient is placed on his face, with his knees straight; cut through the skin and fascia lata to the extent of three inches on the outer border of the semi-membranosus muscle; press the muscle inward and the artery will be felt, with the vein and popliteal nerves