FRACTURE OF THE UPPER END OF THE ULNA
#Fracture of the olecranon# is a comparatively common injury in adults. It usually follows a fall on the flexed elbow, and results from the direct impact, supplemented by the traction of the triceps muscle. In a few cases it has been produced by muscular action alone.
The line of fracture may pa.s.s through the tip of the process, or through its middle, less frequently through the base. It may be transverse, oblique, T- or V-shaped, but is rarely comminuted or compound.
_Clinical Features._--As the fracture almost invariably implicates the articular surface, there is considerable swelling from effusion of blood into the joint. The power of extending the forearm is impaired, and other symptoms of fracture are present. The amount of displacement depends upon the level of the fracture, and the extent to which the aponeurotic expansion of the triceps is torn. As the fracture is usually near the tip, the displacement is comparatively slight, the prolongation of the fibres of insertion of the triceps on to the sides and posterior part of the process holding the small fragment in position; and the fracture may easily escape recognition. When the line of fracture is nearer the base, however, the contraction of the triceps tends to separate the fragments widely (Fig. 35), and a distinct gap, which is increased on flexing the elbow, may often be felt between them, and if the elbow is pa.s.sively extended, the fragments may be brought into apposition, and crepitus elicited.
[Ill.u.s.tration: FIG. 35.--Radiogram of Fracture of Olecranon Process, showing marked degree of displacement.
(Sir Robert Jones" case. Radiogram by Dr. D. Morgan.)]
When there is little displacement, bony union may result, but in many cases the fragments are united only by fibrous tissue. The upper fragment sometimes forms attachments to the shaft of the humerus, and this leads to stretching of the fibrous band between the fragments and to marked wasting of the triceps.
Separation of the olecranon _epiphysis_ is one of the rarest forms of epiphysial detachment (Poland). When the epiphysis is displaced upwards and unites in this position, it may interfere with complete extension of the elbow.
_Treatment._--It would appear that too much stress has. .h.i.therto been laid on the necessity of bringing the fragments into perfect apposition, and too little attention paid to the importance of maintaining the functions of the triceps and the movements of the elbow-joint.
Ma.s.sage and movements are carried out from the first, and the forearm is supported in a sling. Full flexion is the last movement to be attempted. In carrying out the movements, the tip of the olecranon is pressed down with the thumb, so that it is obliged to follow the movements of the ulna, and is prevented from adhering to the humerus.
It was formerly the practice to have the arm almost, but not quite, fully extended, and a Gooch splint, extending from the lower border of the axilla to the finger-tips, and cut to the shape of the extended limb, applied anteriorly and fixed in position by a bandage, the region of the elbow being covered by a convergent spica.
_Operative Treatment._--Operative treatment may be had recourse to, particularly in cases in which there is wide separation of the fragments. The fracture is exposed, the joint cavity opened up and cleared of clots, and silver-wire sutures pa.s.sed through the fragments without encroaching upon the articular cartilage. The limb is fixed with the elbow-joint in the position of almost complete extension.
Movement may be commenced at the end of a week, the angle at which the joint is fixed being changed morning and evening. During the day the flexed position should be maintained and the arm carried in a sling; during the night the limb is fixed to a pillow in the extended position. The patient is allowed to use the joint cautiously within a fortnight.
_Old-standing Fracture._--When union fails to take place, the interval between the fragments tends to increase by the contraction of the triceps gradually stretching the intermediate fibrous tissue, so that a wide gap comes to separate the fragments. It is quite common that the function of the arm is all that can be desired in spite of a gap between the fragments, but, if this is not the case, the fragments may be united by operation.
#Fracture of the coronoid process# is rare except as a complication of backward dislocation of the elbow. It may be produced by direct violence, as well as by muscular action. As the fracture is usually within a quarter of an inch of the tip, the fibres of insertion of the brachialis prevent displacement. The ordinary evidence of fracture is often absent, and the diagnosis is seldom completed without the aid of the X-rays. The treatment consists in flexing the elbow and supporting the forearm in a sling. In some cases a.s.sociated with dislocation, however, the small fragment has been so far displaced as to become attached to the back of the humerus (Annandale).
FRACTURE OF THE UPPER END OF THE RADIUS
Intra-capsular fracture of the #head of the radius# may result from direct violence, from a fall on the p.r.o.nated hand, or from forcible p.r.o.nation or abduction--that is, deviation of the forearm to the radial side. It may accompany dislocation of the elbow or fracture of adjacent bones. The head may be completely separated, or may be split into two or more fragments. Up to the seventeenth year, the _epiphysis_, which is entirely intra-articular, may be separated.
The _clinical features_ are localised pain, crepitus, interference with p.r.o.nation and supination, while the elbow can be almost fully extended and flexed, and in some cases the fragment may be felt through the skin, although it usually continues to move with the shaft in p.r.o.nation and supination.
Union generally takes place satisfactorily, but in some cases the fragments form new attachments resulting in impaired movement at the elbow, and necessitating operative interference.
Fracture of the #neck of the radius# between the capsule and the tubercle is rare.
#Avulsion of the tubercle# may occur from forcible contraction of the biceps, or, in children, from traction made on the forearm (A. L.
Hall).
These injuries are treated with the elbow in the flexed position, and ma.s.sage and movement are carried out as already described.
DISLOCATION OF THE ELBOW
Dislocations of the elbow-joint may involve one or both bones of the forearm, and may be complete or incomplete.
#Dislocation of both bones backward# is the most common of all dislocations of the elbow, and is the only dislocation that is frequently met with in children. It usually results from a fall on the outstretched hand, causing hyper-extension of the joint with abduction--that is, deviation towards the radial side; but it may follow a direct blow on the back of the humerus, a fall on the elbow, or a twist of the forearm.
[Ill.u.s.tration: FIG. 36.--Backward Dislocation of Elbow, in a boy aet.
10, caused by a fall off a wall, landing on the elbow.]
_Morbid Anatomy._--All the ligaments of the elbow, except the annular (orbicular), are torn or stretched. The radius and ulna pa.s.s backward, the coronoid process coming to rest opposite the olecranon fossa behind the humerus, and the head of the radius behind the lateral condyle. The condyles of the humerus bear their normal relations to one another. The olecranon and the triceps tendon form a marked prominence on the back of the elbow, the tip of the olecranon lying above and behind the condyles. The lower end of the humerus lies in the flexure of the joint with the biceps tendon tightly stretched over it. The coronoid process is often broken, or the tendon of the brachialis torn. The median and ulnar nerves may be stretched or torn.
Not infrequently the bones of the forearm are displaced towards the medial side as well as backward.
Occasionally, as a sequel to the dislocation, processes of bone develop in relation to the insertion of the brachialis and interfere with the movements of the joint. These outgrowths are due to displacement of bone-forming elements, either at the time of the original injury or as a result of forcible efforts at reduction.
According to D. M. Greig, they do not develop in the tendon of the brachialis, but under it, and are not of the nature of myositis ossificans. In from four to six weeks after reduction of the dislocation, the movements begin to be restricted, and a hard ma.s.s can be felt in the cubital fossa, which with the X-rays is seen to be a bony outgrowth springing from the quadrilateral s.p.a.ce on the front of the elbow below the coronoid process (Fig. 37). This gradually increases in size and leads to fixation of the joint. In most cases the effects reach their maximum in about six months, and then reabsorption of the ma.s.s begins.
[Ill.u.s.tration: FIG. 37.--Bony Outgrowth in relation to insertion of Brachialis Muscle, following Backward Dislocation of Elbow.
(Sir Robert Jones" case. Radiogram by Dr. D. Morgan.)]
If the disability shows no sign of abatement within a year, or if the bony outgrowth is producing pressure effects on the median nerve, it should be removed by operation.
It is important not to mistake this condition for the effects of a fracture which has complicated the dislocation and been overlooked at the time of the accident.
[Ill.u.s.tration: FIG. 38.--Radiogram of Incomplete Backward Dislocation of Elbow.]
_Clinical features._--The elbow is held fixed at an angle of about 120, p.r.o.nated or midway between p.r.o.nation and supination. Any attempt at movement causes great pain, and is followed by an elastic rebound to the abnormal position. The antero-posterior diameter of the joint is increased, and the forearm, as measured from the lateral epicondyle to the tip of the styloid process of the radius, is shortened to the extent of about an inch. If examined before swelling ensues, the outlines of the articular surfaces may be recognised in their abnormal positions, but swelling usually comes on rapidly, and, by obscuring the bony landmarks, renders the diagnosis difficult.
This injury has to be diagnosed from supra-condylar fracture with backward displacement of the lower fragment and from separation of the lower humeral epiphysis. A general anaesthetic is often necessary to enable an accurate diagnosis to be made. When the deformity is once reduced, there is no tendency to its reproduction unless the coronoid process is also fractured. In a considerable number of cases--according to E. H. Bennett, in the majority--this dislocation is _incomplete_, the coronoid process resting at the level of the trochlea, and the backward projection of the olecranon being scarcely appreciable. The head of the radius, however, is unduly prominent. In such cases the lesion is liable to be overlooked, and therefore to go untreated, leading to permanent stiffness at the elbow.
#Dislocation forward# is much less common than the backward variety.
It is produced by severe force acting from behind on the flexed elbow, the ulna being driven forward, tearing the ligaments of the joint and the muscles attached to the condyles. The olecranon is frequently fractured at the same time (Fig. 39). When it remains intact, it may rest below the condyles (incomplete or first stage of dislocation), or may pa.s.s in front of them, especially if the triceps is ruptured (complete or second stage). The forearm is lengthened, the elbow slightly flexed, the posterior aspect of the joint flattened, and the condyles, in their abnormal relationship, can be palpated from behind.
#Medial and Lateral Dislocations.#--Dislocation towards the ulnar side is always incomplete, some portion of the articular surface of the bones of the forearm remaining in contact with the condyles.
The dislocation to the radial side is also incomplete as a rule, although cases have been recorded in which complete separation had taken place.
These forms of dislocation are rare, that towards the ulnar side being more frequently observed. Each form is often combined with other injuries in the vicinity.
The most common cause of these dislocations is a fall on the outstretched hand, the forearm at the moment being strongly p.r.o.nated.
Forced abduction favours the displacement to the ulnar side; adduction to the radial side. The limb is held flexed and p.r.o.nated, and the facility with which the bony points can be palpated renders the diagnosis easy.
In a few cases _diverging dislocations_ have been met with, the radius and ulna being separated from one another, the annular (orbicular) ligament being torn and no longer holding them together.
#Treatment of Dislocations of Elbow.#--The chief obstacle to reduction is the spasmodic contraction of the muscles pa.s.sing over the joint, and, in the backward variety, the hitching of the coronoid process against the edge of the olecranon fossa. In recent cases, to effect reduction the patient is seated on a chair, while the surgeon grasps the humerus and wrist, and places his knee in the bend of the elbow.
The limb is first fully extended, or even hyper-extended, to relax the triceps and free the coronoid process. Traction is then made in opposite directions upon the forearm and arm, the surgeon"s knee meanwhile making pressure, in a backward direction, upon the lower end of the humerus. The joint is next slowly flexed, and the bones slip into position, often with a distinct snap. If the patient be anaesthetised, these manipulations must be adapted to the rec.u.mbent position.
When some days have elapsed before reduction is attempted, forcible manipulations are to be deprecated as they greatly increase the risk of ossification occurring in relation to the brachialis (D. M. Greig); and recourse should be had to open operation, and the tearing or bruising of the soft parts should be reduced to a minimum.
After reduction, the limb is flexed to rather less than a right angle and supported by a sling. Ma.s.sage and movement are commenced at once.
Fracture of the coronoid process predisposes to recurrence of the dislocation; when this complication exists, therefore, the limb should be fixed at an acute angle, and movements of full extension postponed for a fortnight. Ma.s.sage and limited movements, however, may be carried out from the first.
If there is a fracture of the olecranon, the treatment must be modified accordingly (p. 87).
[Ill.u.s.tration: FIG. 39.--Forward Dislocation of Elbow, with Fracture of Olecranon.