sure, hand twisted, and the kick-back of gasoline engine.

Considerable dispute has been waged as to the true mechanism of a Colles' fracture. The following two forces are considered by authorities to be the factors which together produce the fracture, namely:

First. The force of avulsion, i. e., the pull exerted by the anterior ligament on the lower end of the radius, especially the projecting anterior lip, by hyperextension. In hyperextension the bones of the carpus and hand act practically as one bone, so that a powerful leverage is brought to bear through the strong anterior ligament on the lower end of the radius. The expanded end of the radius with its cancellated structure makes it less able to stand a tearing force. This fact makes the radius, when submitted to a strain, weaker than the ligament, and consequently it breaks first.

Second. The force of impact, i. e., the force made up of the weight of the body and the velocity of a fall which has been sustained and which remains and is exerted after the force of avulsion has been expended. This is the socalled breaking strain received somewhat up

ward and backward, and by most authorities is considered to be more important than the tearing strain or hyperflexion produced by the strong anterior ligament. By this force a wedge-like impact of the carpus or anatomical condyle against the articular cup of the base of the radius in an upward and backward direction is sustained. Very frequently also, if the momentum be great, the lower fragment is split and mushroomed and the fragments thrown out in various directions by the descent into it of the lower end of the upper fragment, after the breaking has been sustained. The amount of this impaction is a fair index of the force which the anatomical structures of the wrist have had to sustain.

The typical deformity of a Colles' fracture is the so-called silver-fork deformity, which consists of an upward and backward tilting of the lower fragment. The plane of the fracture is oblique from below upward and backward. With this upward and backward tilting of the lower fragment, the angle of the carpal articular surface of the radius is altered, so that in place of its facing normally slightly forward and downward to facilitate flexion of the wrist,

FIGURE 5.

Radiograph showing (A) normal wrist, and (B) Colles' fracture in opposite wrist. Note upward and backward tilting of lower fragment, and contrast the difference in the planes of the articular surfaces of the radius in the normal and injured wrist. In the normal wrist the plane looks downward and forward, while in the injured wrist it looks upward and backward. We must overcome this difference in our reduction.

it faces upward and backward, thus producing the fork handle. The wrist, as it is pressed upwards and backwards, tends to carry with itself the lower fragment of the radius which has been torn or broken off, and the extent of the displacement is limited only by the resistance of the fibrous structures binding the wrist and by the amount of the force that the fall has produced.

In addition to the backward displacement of the lower fragment of the radius, there is also a lateral displacement toward the radial side, which makes the ulna stick out conspicuously. This displacement of the lower fragment is always toward the radial side of the wrist, never toward the ulnar. It is brought about by the carpal mass, that is the hand and wrist, after the breaking of the radius, slipping back in the direction of supination, the whole mass rotating around the head of the ulna because of the attachment of one of the bands of the anterior common ligament above mentioned to the styloid process of the ulna. Sometimes the strain is so great on this band of the ligament that the styloid process of the ulna is torn off. The lower end of the shaft of the radius appears to be thrust forward and this exaggerates the

appearance of lateral displacement of the lower fragment. There is, however, actual lateral displacement, as the X-ray shows, but the chief element is the supinating rotation which brings the lower fragment into lateral prominence.

As the lower fragment is displaced upwards and backwards by the force of avulsion and impact, it tends to strip up a layer of periosteum on the dorsal surface of the radius. This periosteum acts as a sort of ligament and interferes with the reduction of the fracture, because it remains tense after the fracturing force has been expended and the hand has again fallen forward, and tends to hold the entangled fragments together. Blood clots accumulate underneath it, since it is lifted up and thus leaves a space between it and the bone for blood to accumulate, and unless there is complete reduction, the space remains and new bone forms underneath it, filling up the blood-clot space, and thus it becomes a factor in the size and extent of the callus and therefore in the amount of subsequent deformity. Complete reduction

obliterates the space filled by blood clot and decreases the amount of callus, because it brings the periosteum back to its normal position. The appreciation of the presence and effect of this band of periosteum gives a hint of the first manipulation in reduction, for we must relax this band to overcome its action and to do that we must put the hand again in hyperextension, in other words, increase the deformity, and that is the first manipulation in the reduction of a Colles' fracture.

In all fractures we should never forget that the soft parts are often more seriously injured than the bone and often require more attention in treatment. This is frequently true in a Colles' fracture. The injuries that are sustained by the soft parts about the wrist joint, coincident with the bone lesion, are often extensive and severe. Ligaments are violently stretched and partially lacerated, and sometimes they are completely ruptured. The synovial sacks of the articulations are badly contused and often torn and filled with blood. Sheaths of tendons, both in front and behind, are injured. In front, the projection of the ragged edge of the upper fragment of the radius into the flexor tendons of the wrist may lacerate their sheaths and irritate the tendons; while behind, the stripping of the periosteum, and its later continued tension, involves in its results the extensor tendons. Effusions, of blood and lymph into the anterior tendon sheaths and connective tissue spaces quickly produce a well-marked swelling on the front of the wrist above the anterior ligament, exaggerating the deformity produced by the bone displacement, and may simulate displacement even after the bones have been reduced. On the back of the wrist some swelling of a similar nature also forms. The effusions are firm and slowly absorbed and tend to provoke adhesions along the course of the tendons which they surround.

In a certain proportion of cases the impact is so great that a shortening of the radius is produced, which it is impossible to wholly overcome in the reduction. Some of the cancelli of the lower fragment are crushed and condensed and in some cases absorption of the osseous tissues later takes place, so that the bone is permanently shortened and the form of its lower

extremity is changed. Such changes in the contour of the bone are an unavoidable result of the accident itself and cannot be entirely prevented by treatment. However, our best efforts should be made to replace the bone, for the first principle in treatment is proper reduction. Any shortening of the radius will make the head of the ulna prominent, as the wrist and hand will fall to the radial side.

Pilcher well stated the prominent characteristics of the deformity remaining in old Colles' fractures when he said: "Prominence of the head of the ulna with widening of the wrist and loss of the anterior projection of the articular tip of the radius and the imposition of a more or less backward inclination upon the plane of the carpal articular surface of the radius, are the most common permanent alterations in the anatomical configuration of the wrist as a result of Colles' fracture."

The characteristic silver-fork deformity proclaims the diagnosis often without further examination. The cardinal signs of fracture, crepitus and abnormal mobility, are often obscured and prevented by the impaction and resistance of untorn fibrous connecting bands.

As a final authority, however, the X-ray should always be used and radiographs taken both antero-posterior and lateral to correct or corroborate the diagnosis, and later to check up the position after reduction.

Colles' fracture should be reduced as quickly as possible after the injury, and general anaesthesia should be the rule. The reduction should be accomplished by very forcible manipulation. The functional result depends upon the proper replacement of the carpal articulating surface of the radius. The articulating surface of the normal radius with the carpus is tilted, so that the dorsal edge of the lower end of the radius is always distal to the palmar edge, and the plane of the articular surface, as stated before, looks forward and downward. This anatomical fact should always be borne in mind when deal ing with a Colles' fracture. The reverse of this position occurs in the fracture.

One of the things that Doctor John B. Murphy liked to talk about in his clinics and "hammer in" was the treatment of Colles' fracture. You will remember that he used to talk as follows: "Now let us take up the proposition of the reduction of the most frequently maltreated fracture that occurs in the body, and one that unreduced gives the most evil results, a Colles' fracture. What is the correct method of effecting complete reduction? A reduction cannot be accomplished unless you first unlock the fragment. How do you accomplish this unlocking? Always with the patient anaesthetized. Place the thumb of the distal hand upon the posterior surface of the distal fragment, and the thumb of the proximal hand upon the nail of the distal thumb, and then increase the deformity almost to a right angle; unlock the fragment; push the lower fragment downward and flex it forward and at the same time swing the hand well around to the ulnar side to overcome the lateral displacement of the lower fragment, that also occurs to the radial side. With the reduction accomplished, dress the forearm by a few recurrent turns of a plaster

of Paris bandage placed upon the posterior surface so as to cover three-fifths of the circumference of the forearm. In Colles' fracture you do not have to retain the lower fragment by nailing except in very rare instances, because after complete reduction the lower fragment will remain in position, even if you dress the fracture merely in a sling. The great mistake and the cause of future trouble in the management of Colles' fracture is the effort made by the surgeon to reduce the fracture by the mere application of a splint. Splints were never intended to be used for the purpose of effecting a reduction of fractures."

Colles' fracture was of greater interest and was better understood by everyone after hearing one of these talks by Doctor Murphy.

To sum up: The cardinal points to be observed in the reduction of a Colles' fracture,

are:

First. Anaesthetize the patient.

Second. Increase the deformity to a right angle or nearly so. This usually breaks up the impaction or entanglement of the fragments.

Third. Push the lower fragment down, flex it forward and swing it well to the ulnar side by strong traction and counter traction on the hand and wrist, and pull it into a position of marked ulnar abduction.

Fourth. At the same time supinate the upper fragment and slightly promote the lower fragment.

These forcible manipulations are done to overcome:

(a) The upward and backing tilting of the lower fragment;

(b) The displacement of the lower fragment to the radial side; and

(c) The supination of the lower fragment that occurs from the rotation around the head

of the ulna.

In practice I use most often the plaster splint as described by Murphy, extending it posteriorly on the forearm from near the elbow down to the distal end of the metacarpal bones, leaving the fingers free. This splint can be removed in a few days and after that changed daily, if desired. I prefer to remove the splint frequently, as it allows one to carry out slight passive motion and gentle massage and the bathing of the skin in alcohol and the readjustment of the

pads to prevent pressure points. Two to three weeks is usually long enough to leave on a fixation dressing. One may use wooden splints if desired, in place of plaster. Regard must always be given to the fact that any pressure brought to bear upon the palmar or anterior surface of the carporadial region may bear upon the projecting anterior lip of the lower fragment and may crowd that fragment back to the plane of the shaft of the bone, even though complete reduction had been secured before the splints were applied. Antero-posterior pressure also tends to crowd the soft tissues in between the radius and ulna and forcing the ulna away, may renew and perpetuate its separation. The first indication, therefore, in the planning of a splint dressing, is the placing to the front of the forearm of a graduated pad of proper thickness, so placed that it will shield the anterior lip of the lower fragment from pressure. The lower edge of this pad should be about one-half inch above the carporadial articulation. It may be about threeeighths of an inch thick and extend upwards about two and a half to three inches. It should be wide enough to wrap part way around the ulna, so as to give support to that bone also, when the roller bandage is applied. A posterior light, straight, wooden splint, well padded, should then be applied and will meet all indications for splint support. It should not be wider than the wrist itself, so as not to interfere with the lateral support of the ulna. It should extend from the upper part of the forearm downward only to the heads of the metacarpal bones, so that the fingers shall not be confined by it. This splint, together with the graduated pad already mentioned to fill up the concavity of the radius and protect the anterior lip on the palmer side, will answer all indications for splints, if one prefers to use them rather than plaster Paris. The arm may then be hung in a narrow sling, supporting the arm on the ulnar side. This will assist also by the weight of the arm in pressing the ulna back into position. After the splints have been discarded, which is usually during the second or third week, active and passive movements of the wrist and fingers with massage should be practiced systematically until the normal function of the part has been restored. In all move

ments and massage, pain should not be produced; gentleness is the rule. In general, the functions of the wrist and hand are usually so far restored, even in bad cases of deformity, that all the ordinary functions and uses of the wrist are restored. The greatest and most prolonged disability is due to adhesions in the tendon sheaths and amongst the periarticular fibrous structures, and sometimes to muscle degenerations caused by prolonged splint pressure and too long immobilization.

In conclusion, I would say that the one thing of greatest importance to do in the treatment of a Colles' fracture is to properly reduce it, and the next most important thing to do is not to abuse the use of splints.

The successful treatment of all fractures requires good judgment, common sense, constant attention to details, a knowledge of many methods, and the election of that method, which in the individual case will lead to a restoration of the form and function of the injured limb in the shortest possible time with the least danger and inconvenience to the patient.

DISCUSSION.

DR. A. R. COLVIN, St. Paul: The subject of Colles' fracture as presented by Dr. Parker is a very interesting one.

A clear understanding of the manner in which the deformity is produced in the typical Colles' fracture is very necessary because the unravelling of the deformity is the key-note to successful treatment.

König in his text book describes the production of deformity as follows:

The patient falls backwards, arresting his weight with the outstretched hand, the force transmitted from the palm of the hand through the anterior ligament of the wrist joint, the lower end of the upper fragment continuing to seek another point of support tends to seek the earth and becomes impacted in the lower spongy fragment, with the resulting familiar silver-fork deformity. The patient continuing to fall, two other items in the deformity are produced and the impaction takes place more on the outer side of the bone, and the hand thus becomes carried to the radial side, rotation through a vertical axis also occurs and the head of the ulna thus becomes rotated towards the palmar aspect of the forearm. The unravelling of this deformity becomes a now simple matter when we apply our force in reduction in the opposite directions to those which produced it.

Reduction must be such that at least the joint surface of the radius points directly forwards in the axis of the shaft. It is not always possible nor necessary