taken to preserve the periosteum. Avoid the brachial artery and the median nerve. Saw the bone

through at a right angle to the shaft above the condyles. Allow the humerus to return into the wound cavity.

Push the ends of the radius and ulna into the opening of the wound. Detach the tissues from the ulna and radius, down to the level of the lower border of the coronoid process. Saw the bones through at this level. The tubercle of the radius is not to be sacrificed, and special care must be given to preserve the attachment of the brachialis anticus to the periosteum. Draw the bones into the wound cavity, and approximate them to the humerus at a right angle.

Wrist. (Excision of the carpus with resection of the carpal ends of the radius and ulna, and of those of the metacarpus.) Place the hand prone and adducted upon the table.

Begin an incision one half of an inch above the wrist-joint, a little nearer to the inner than to the outer border of the dorsal surface of the radius, and continue it downward to the middle of the dorsal surface of the second metacarpal bone. Divide the integument and fascia, the tendon of the extensor carpi radialis brevior muscle, the periosteum, and posterior ligaments.

On the radial side of the incision, detach by means of a scalpel the extensor carpi radialis longior from the second metacarpal bone. Extend the wrist, and use an elevator to separate the remaining attachments, guarding against wounding the radial artery. Retract the tissues and separate by means of bone-nippers the trapezium from the remainder of the carpus.

On the ulnar side of the incision, the wrist being extended, separate by means of an elevator the tis sues from the bones.

Begin a second incision two inches above the wrist-joint, between the flexor carpi ulnaris and the ulna, and continue it downward to the level of the middle of the fifth metacarpal bone. This incision should run just anterior to the ulna and the fifth metacarpal bone. Separate by means of a scalpel the attachment of the extensor carpi ulnaris from the fifth metacarpal bone. Extend the wrist, and complete the separation of the tissues from the dorsal surface of the bones.

Flex the wrist and separate the tissues from the palmar surface, cutting the pisiform bone and the unciform process from the rest of the carpus, by means of the bone-cutting forceps. Do not use the scalpel in separating the tissues below the heads of the metacarpal bones, on account of the proximity of the deep palmar arch.

Retract the tissues above and below, and by means of cutting forceps separate the carpus from the radius and triangular cartilage above and from the metacarpus below. The carpus can now be removed through the wound on the ulnar side. Dissect out the trapezium, avoiding the radial vessels, and the pisiform bone and the unciform process, avoiding the ulnar vessels and nerve.

Push the metacarpal bones into the wound, and saw off their articular surfaces. Separate the tissues from the head of the ulna, avoiding the ulnar vessels and nerve, and saw off its articulating surfaces. Separate the tissues from the carpal end of the ra

dius, avoiding the radial vessels. Protrude the bone and saw off its articulating surface on a level with the sawn end of the ulna.

Search for the detached tendons of the extensors of the carpus, shave off slightly their surface toward the dorsum of the hand, and attach them with catgut to the periosteum over the sawn ends of their respective metacarpal bones. Appose to the sawn ends of the radius and ulna those of the metacarpus.

Metacarpophalangeal.-Place the hand, with the fingers extended, prone upon the table.

Make an incision two inches long over the dorsal surface of the bones, with its middle point over the joint. In the case of the thumb, the incision should be a little to the radial side, and in case of the little finger, a little to the ulnar side of the middle of the dorsal surface. Divide the integument and fascia. Push aside the dorsal tendons and incise the periosteum. Separate by means of an elevator the perios teum from the ends of the bones for half an inch, and cut the ligaments of the joint. Forcibly flex the joint to protrude the head of the metacarpal bone. Saw off the articular surface. Protrude the base of the phalanx through the wound, and saw off its articular surface.

Phalangeal.-Extend the finger.

Make longitudinal incisions, about an inch long, on the sides of the finger nearer the dorsal than the palmar surface. The middle of the incisions should correspond to the joint. Divide the tissues to the bones. Elevate the tissues from the head of the proximal phalanx, and divide the lateral ligaments of the joint. Bend the finger laterally to protrude the

head of the proximal phalanx. Saw off the head of the proximal phalanx. Push the base of the more distal phalanx into the opening, and separate the tis sues from its base by means of a scalpel. Protrude the end of the bone and saw off the articular surface.

Hip (Langenbeck).-Place the subject on the back, inclined to the opposite side. Flex the hipjoint until the thigh is at an angle of 45° with the axis of the body.

Make an incision about six inches long in the axis of the limb, with its middle point over the middle of the superior border of the great trochanter. Divide the integument and fasciæ. Incise the perios teum on the trochanter, and separate, by means of the scalpel and elevator, the tissues from the superior border and outer surface. Separate the fibers of the gluteus maximus muscle, and divide on a director the fascia covering its deep surface.

Push aside the tissues to expose the neck of the femur and retract the sides of the wound. Incise the capsule and periosteum, cutting on the long axis of the neck of the femur. Separate the tissues from the neck. The attachment of the obturator externus muscle must be cut from the digital fossa with care.

1. Incise in several places the cotyloid ligament, so that air can enter the acetabulum. Adduct and forcibly rotate inward the joint, partially dislocating the head of the femur. Divide the ligamentum teres against the head of the femur, when the dislocation is easily completed.

Pass a chain-saw around the neck of the femur, and saw through the bone, protecting the soft parts.

The acetabulum is readily examined, the sides of the wound being retracted.

2. If an excision is to include the division of the bone just above the level of the lesser trochanter, other attachments must be separated before the head of the bone is dislocated. Cut the periosteum at a right angle to the longitudinal incision, carrying the knife as far around the bone as possible. This horizontal incision of the periosteum should be on the level of the middle of the trochanter. Separate all the tissues down to the level of the lesser trochanter. Now the head of the bone is to be dislocated, and the chain-saw passed behind the bone above the lesser trochanter. Divide the bone just above the level of the lesser trochanter, protecting the soft parts from contact with the saw.

Knee.-Place the subject on the back, with the knee-joint semi-flexed.

Begin an incision just below the adductor tubercle on the internal condyle, and extend it across the front of the limb below the patella to a corresponding part of the external condyle of the femur. Divide all the tissues to the bone, opening widely the joint. Flex the joint, and carefully cut the crucial ligaments.

The lateral ligaments having been completely divided against the condyles, the posterior surface of the femur is readily reached. Separate the tissues as far back as the posterior surfaces of the condyles, protecting with the thumb the popliteal artery. Retract the tissues and divide the bone by means of a Butcher's saw from behind forward. Do not remove so much bone as to include the posterior articular surfaces of