Dislocation on to the pubes is a further degree of the obturator form (Fig. 71). It is usually produced by forcible hyper-extension and lateral rotation of the hip, such as occurs when the body is bent back while the thigh remains fixed.

The capsule is torn farther forward than in the other varieties, and the head rests on the horizontal ramus of the pubes against the ilio-pectineal line.

Clinical Features.—There is marked eversion, flexion, and abduction, but the shortening is inconsiderable. The ilio-psoas and [inverted Y]-ligament are tense. The head of the femur may be felt in the groin, with the femoral vessels over, or to one or other side of it. There is sometimes pain and numbness in the distribution of the femoral (anterior crural) nerve. The prominence of the great trochanter is lost.

Treatment of Dislocation of the Hip.—For the reduction of a dislocation of the hip complete anaesthesia is necessary, and the patient should be placed on a firm mattress on the floor to give the surgeon the best possible purchase upon the limb. The surgeon grasps the ankle with one hand, while the other is placed behind the head of the tibia, the leg being held at right angles to the thigh. An assistant meantime steadies the pelvis by making firm pressure over the iliac crests.

As the chief obstacle to reduction is the tension of the ilio-femoral ligament, the first indication is to relax this structure by flexing the hip to its fullest extent.

In the backward varieties (dorsal and sciatic) the [inverted Y]-ligament is relaxed by flexing the thigh upon the pelvis in the position of adduction. The thigh is then fully abducted, to cause the head of the bone to retrace its steps forwards towards the rent in the capsule; and at the same time rotated laterally to relax the rotator muscles. This combined movement tends also to open up the rent in the capsule. Finally, the limb is quickly extended to cause the head to enter the socket. This object is often aided by making vertical traction or lifting movements on the abducted and laterally rotated limb before extending.

For the reduction of the forward varieties (obturator and pubic), the thigh is first fully flexed on the pelvis, but in the abducted position. The limb is then strongly rotated medially and abducted, and finally extended. Lifting movements may be found useful in these cases also.

All methods of reduction by forcible traction on the extended limb are to be avoided, as they fail to meet the primary indication of relaxing the [inverted Y]-ligament.

After reduction, the limb is steadied by sand-bags; massage is carried out from the first, and movement after a few days. The range of movement is gradually increased, and the patient is allowed to use the limb with caution in from two to three weeks.

When the rim of the acetabulum has been fractured, the patient must be confined to bed with extension for six to eight weeks, to avoid the risk of re-dislocation.

Changes of the nature of chronic arthritis are liable to occur in and around the joint in old and rheumatic subjects; and atrophy or paralysis of muscles may follow, if their nerves are implicated.

Old-standing Dislocation.—It is impossible to lay down any time-limit for attempting reduction in old-standing dislocations of the hip. Manipulation may succeed in cases of some months' standing, and may fail when the bone has been out only a few weeks. In certain cases, even after reduction has been effected, there is a marked tendency to re-displacement. In any case, the attempt does good by breaking down adhesions, provided no undue force is employed such as may damage the sciatic nerve or vessels, or fracture the neck of the femur, and success may attend on a second or even a third attempt at intervals of from three to five days. If manipulation fails, and if the deformity is great and the usefulness of the limb seriously impaired, an attempt may be made to effect reduction by operation; the operation, however, is one of considerable difficulty, and in the event of failure the head of the bone should be excised. If the head has formed a new socket for itself and there is a fairly useful joint, the condition should be left alone.

Congenital dislocation of the hip is described with Deformities of the Extremities.

Sprain of the hip is comparatively rare. It results from milder degrees of the same forms of violence as produce dislocation. The ligaments are stretched or partly torn, and there is effusion of fluid into the joint. Pressure over the joint elicits tenderness; and the limb assumes the position of slight flexion, abduction, and lateral rotation, but there is no alteration in length. Such injuries, unless carefully treated by massage and movement from the outset, are apt to be followed by the formation of adhesions, resulting in stiffness of the joint.

Contusion in this region, on the other hand, is not uncommon. It is produced by a fall on the trochanter, and gives rise to symptoms which simulate to some extent those of fracture of the neck. The limb lies in the position of slight flexion, but the bony points retain their normal relationship to one another, and there is no shortening. The swelling and tenderness often prevent a thorough examination being made, and when any doubt remains as to the diagnosis, the patient should be kept in bed till the doubt is cleared up by the use of the X-rays. If the bone has been broken, this will reveal itself in the course of a few days by the occurrence of shortening and other evidence of fracture.

In elderly patients, contusion of the hip may be followed by changes in the joint of the nature of arthritis deformans; and it has been stated, although proof is wanting, that absorption of the neck of the femur sometimes occurs. These injuries are treated by rest in bed, massage, and the other measures already described as applicable to sprains and contusions.

FRACTURE OF THE SHAFT OF THE FEMUR

This group includes all fractures between that immediately below the lesser trochanter and the supra-condylar fracture.

In adults, when due to direct violence, the fracture is usually transverse, and may be attended with comparatively little displacement. Indirect violence, on the other hand, usually produces an oblique fracture, which is frequently comminuted and often compound. The break is most commonly situated a little above the middle of the shaft, the obliquity being downward, forward, and medially, and of such a nature that the fragments tend to override one another (Fig. 75). The most serious forms are those associated with gun-shot wounds.



The direction and nature of the displacement depend more upon the fracturing force, the weight of the lower part of the limb, and the action of the muscles attached to the respective fragments, than upon the direction of the obliquity. As a rule, the proximal fragment passes forward and laterally, and is maintained in this position by the ilio-psoas and glutei muscles, while the distal fragment is displaced upward and medially and is rotated outward by the combined action of the weight of the limb, the longitudinal muscles, and the adductors.

Clinical Features.—The limb is at once rendered useless, and there is great swelling from effusion of blood in the region of the fracture. This, together with the muscularity of the part, often renders an accurate diagnosis as to the site and direction of the fracture exceedingly difficult. The shortening varies from 1/2 inch to 3 or 4 inches—averaging about 1 inch in adults—and eversion is always marked. Mobility may be detected and crepitus elicited without disturbing the patient, by placing the hand under the seat of fracture and gently attempting to raise the limb; or by fixing the proximal fragment by one hand placed in front of it while the distal part of the limb is carefully lifted. It will be found that the great trochanter does not rotate with the lower segment of the femur. These tests must be employed with great caution lest the deformity be increased or the fracture rendered compound.

In many fractures of the thigh, and especially in those produced by indirect violence, the knee is sprained, and there is a considerable effusion into the joint, and this may lead to stiffness unless massage is employed from the outset.

Treatment.—Fracture of the shaft of the femur is one of the most difficult fractures in the body to treat successfully. In cases of oblique fracture, the patient should be warned that shortening to the extent of from 3/4 to 1 inch is liable to result, however carefully the treatment may be carried out. This does not necessarily imply a permanent limp, as by tilting the pelvis he may be enabled to walk quite well; if this is not sufficient to equalise the length of the limbs, the sole of the boot may be raised. A general anaesthetic is necessary to ensure accurate reduction, and extension must be applied to maintain the fragments in apposition and prevent shortening. The splint which has been found most generally useful is the Thomas' knee splint, the ring of which rests against the ischial tuberosity. To admit of flexion at the knee the Thomas' splint should have a hinged attachment on which the leg is supported. This leaves the knee free and allows of movement being made to prevent stiffness. The limb is suspended by broad strips of flannel or linen, fixed to the side bars of the splint by means of safety pins or strong spring paper clips.

In simple fractures extension may be obtained by means of broad strips of adhesive plaster applied to each side of the thigh and reaching well above its middle. The plaster is secured by a bandage, and to its lower ends are attached broad tapes which are buckled to a stirrup through which traction is made by means of a cord passing over a pulley fixed to an upright at the foot of the bed.

The lower end of the splint is suspended, and the counter-extension is obtained by pressing the ring against the ischial tuberosity. To prevent the ring overriding the tuberosity and pressing on the soft tissues of the buttock, it is slung by the rope to a cross-bar above the bed, e.g. the Balkan frame (Fig. 81).

In compound fractures the presence of a wound may prevent adhesive plaster being used, and it is necessary to take the extension directly through the bone. A posterior gutter splint is applied to prevent sagging. After pulling the skin upward, a small incision is made over the upper expanded border of each condyle, and the points of an ice-tong calliper are made to grip the bone without penetrating into the cancellous tissue. A cord attached to the handles of the calliper passes over a pulley and supports the weight necessary to give the desired amount of traction (Fig. 81).

An alternative method of exerting traction directly through the bone is by means of Steinmann's apparatus (Fig. 76). In a moderately muscular adult, a weight of from 12 to 15 pounds by means of strips of plaster applied to the skin, or 10 to 25 pounds by direct traction on the bone, should be applied in the first instance. The correct weight to employ is that which maintains the length of the limb at its normal, and is therefore liable to revision from time to time.



Hodgen's splint is a comfortable and efficient means of treating these fractures, as it allows the patient a certain amount of movement, admits of the part being massaged, and facilitates nursing.

It consists of a wire frame (Fig. 77) to one side of which a series of strips of flannel about 4 inches wide are attached. Extension strapping is first applied, and then the frame, which extends from the level of Poupart's ligament to well beyond the sole, is placed over the front of the limb, and the loose ends of the flannel strips brought round behind the limb, and fixed to the other side of the frame, convert it into a sling. The tapes attached to the extension strapping are now tied to the end of the frame. By suspending the limb in this splint by means of cords passing obliquely over a pulley attached to an upright at the foot of the bed, the weight of the limb is made to act as the extending force.



The retentive apparatus should be worn for from six to eight weeks, after which the patient is allowed up with crutches, which he usually requires to use for three or four weeks longer, before he can bear his weight upon the limb. The old dictum of Nelaton, that the treatment of fracture of the thigh should last for a hundred days, is a safe working-rule. In fractures of the shaft an ordinary Thomas' knee splint, or a "walking calliper splint" which is fixed to the heel of the boot, may be worn when the patient gets up.

Union may be exceedingly slow in fracture of the femur, and may even be delayed for months. Mal-union sometimes occurs, the fracture uniting with an angular deformity outward and forward.

Re-fracture is liable to occur if the patient falls or twists the limb within a few months of the original injury. It has happened not infrequently just after the retentive apparatus has been removed from the nurse raising the limb by the foot in order to wash it.

Liston's long splint is only employed as a temporary expedient for immobilising the fragments during transport; a Thomas' splint, if available, is better for this purpose.



Operative treatment is sometimes called for when simpler measures fail to reduce the displacement, and in cases of un-united fracture or of vicious union. The incision, which must be free, is preferably placed in the line of the lateral intermuscular septum; the periosteum is interfered with as little as possible. The application of extension by the calliper method is often of great service, during the operation, in enabling the operator to get the fragments into position; sometimes no fixation is required, but, if necessary, recourse is had to plating or pegging, or an intra-medullary pin. The extension apparatus is retained for three or four weeks. The after-treatment is carried out on the same lines as for simple fracture, but the retentive apparatus must be worn for a considerably longer period.



Fracture of the Femur in Children.—In children, especially below the age of ten, this fracture is quite common. It is often of the greenstick variety, or, if complete, is transverse and sub-periosteal, and as it is accompanied by few symptoms and but little deformity, is liable to be overlooked.

When there is displacement, the deformity is similar to that in adults, and the treatment is carried out on the same lines.

In young children the nursing is greatly facilitated by applying vertical extension to one or both lower extremities (Fig. 79). If the fracture is transverse and shows little tendency to displacement, the local Gooch splints may be dispensed with; in any case, massage should be employed from the first.

The patient may be allowed out of bed in from three to four weeks, wearing a retentive apparatus.

The shaft of the femur is sometimes fractured during delivery, particularly in breech cases. The simplest and most efficient means of controlling the fracture is by extension strapping fixed to the lower end of a Thomas' knee splint.



CHAPTER VII

INJURIES IN THE REGION OF THE KNEE AND LEG

Surgical Anatomy—FRACTURE OF LOWER END OF FEMUR: Supra-condylar; T- or Y-shaped; Separation of epiphysis; Either condyle—FRACTURE OF UPPER END OF TIBIA: Of head; Separation of epiphysis; Avulsion of tubercle—DISLOCATIONS OF KNEE: Dislocations of superior tibio-fibular joint—INTERNAL DERANGEMENTS OF KNEE—INJURIES OF PATELLA: Fractures; Dislocations—INJURIES OF LEG: Fracture of both bones; Fracture of tibia alone; Fracture of fibula alone.

INJURIES IN THE REGION OF THE KNEE

These include the supra-condylar fracture of the femur, the T- or Y-shaped fracture opening into the joint, separation of the lower femoral epiphysis; fracture of the head of the tibia, and separation of its upper epiphysis; the various sprains and dislocations of the knee, as well as its internal derangements; and fractures and dislocations of the patella.

Surgical Anatomy.—Of the two epicondyles the medial is the more prominent and palpable. The adductor tubercle, which is situated on the upper and back part of the medial epicondyle, gives attachment to the round tendon of the adductor magnus, and marks the level of the epiphysial line and of the upper limit of the trochlear surface of the femur. Between the medial condyle of the femur and the medial condyle (tuberosity) of the tibia, when the limb is in the flexed position, the line of the joint can be recognised as a groove or cleft, and this is made use of in measuring the length of the tibia. The lateral condyle (tuberosity) of the tibia can also be palpated, and must not be mistaken for the head of the fibula, which lies farther back and at a slightly lower level, and can readily be identified by tracing to it the tendon of the biceps. The tuberosity of the tibia, into which the quadriceps extensor tendon is inserted, lies on the same level as the head of the fibula. In the extended position of the limb, the patella is loose and movable on the front of the trochlear surface of the femur, while in the flexed position it sinks between the condyles, resting chiefly on the lateral one and becoming fixed.

The popliteal artery and vein and the tibial (internal popliteal) nerve lie in close relation to the posterior aspect of the joint; and the common peroneal (external popliteal) nerve passes behind and to the medial side of the biceps tendon.

The knee is an example of a joint which depends for its strength chiefly on its ligaments. Not only are the tibial and fibular collateral (external and internal lateral) ligaments and the posterior part of the capsular ligament particularly strong, but the cruciate ligaments and the menisci (semilunar cartilages) inside the cavity of the joint further add to its stability. The powerful tendon of the quadriceps extensor muscle, in which the patella is developed as a sesamoid bone, protects and strengthens the front of the joint and functionates as the anterior ligament of the joint. In the attitude of complete extension in which the joint is locked, no demand is made on the quadriceps apparatus; with the commencement of flexion, the stability of the joint, and the weight-bearing capacity of the limb as a whole, depend largely on the controlling influence of the quadriceps muscle; this becomes evident on going down an incline and more markedly on going down stairs. Hence it is, that in recurrent sprains of the knee, including under this term the various forms of internal derangement of the joint, the wasting with loss of tone of the quadriceps is an important factor in aggravating the disability of the limb and in retarding and preventing recovery. In the treatment of recurrent sprains of the knee, therefore, special attention must be directed towards the wasting of the quadriceps by means of massage and appropriate exercises.

The synovial cavity extends from the level of the head of the tibia to an inch or more above the trochlear surface of the femur, passing slightly higher on the medial aspect of the joint than on the lateral (Fig. 80). The large bursa between the quadriceps muscle and the femur (sub-crural bursa) generally communicates with the cavity of the joint. The synovial cavity of the superior tibio-fibular articulation is usually distinct from that of the knee-joint, but may communicate with it through the popliteal bursa.



A large bursa (pre-patellar) lies over the lower part of the patella and upper part of the ligamentum patellae; and a smaller one separates the ligamentum patellae from the tuberosity of the tibia. Several important bursae are found in the popliteal space, one of which—the semi-membranosus bursa—sometimes communicates with the knee-joint.

FRACTURE OF THE LOWER END OF THE FEMUR

Fractures involving the lower end of the femur, especially the supra-condylar and T-shaped fractures, are to be looked upon as serious injuries, on account of the difficulties attending their treatment, and the risk of damage to the popliteal vessels and of impairment of the usefulness of the knee-joint.

Supra-condylar fracture is usually the result of a fall on the feet or knees, or of direct violence, and is most common in adult males. The line of fracture is generally irregularly transverse, or it may be slightly oblique from above downwards and forwards, so that the proximal fragment passes forward towards the patella, while the distal is rotated backward on its transverse axis by the gastrocnemius muscle.

Clinical features.—Soon after the accident a copious effusion of blood and synovia takes place into the cavity of the knee-joint, adding to the swelling caused by the displaced bones, and rendering it difficult to recognise the precise nature of the lesion. As it is important to make an accurate diagnosis, the X-rays should be employed if possible, and a general anaesthetic should be given when necessary.

The proximal end of the distal fragment is usually palpable in the popliteal space, while the proximal fragment is unduly prominent in front. By flexing the knee the fragments may be brought into apposition and crepitus elicited. In oblique fractures, the pointed lower end of the proximal fragment may transfix the quadriceps extensor muscle and may be felt under the skin, or it may perforate the skin and thus render the fracture compound. It should be disengaged by fully flexing and making traction on the knee. The thigh is shortened to the extent of from 1/2 to 1 inch.

The popliteal vessels lie so close to the bone that they are liable to be torn by the displaced distal fragment, giving rise to the usual signs of ruptured artery. Sometimes, owing to the feeble state of the circulation from shock, the bleeding does not take place at the time of the accident, but ensues some hours later. The vessels may merely be pressed upon by the displaced bone, but the nutrition of the limb beyond is endangered and gangrene may ensue if early reduction be not effected.

Treatment.—The small size of the distal fragment, its depth from the surface, and the accompanying effusion into and around the joint, render its control difficult. In the majority of cases the two fragments can only be brought into apposition when the knee is flexed on the thigh and the thigh on the pelvis, and it is almost always necessary to carry out the reduction under anaesthesia.

In the few cases in which the fragments can be accurately approximated in the extended position of the limb, retention may be effected by means of a box splint reaching well up the thigh (p. 180).

In the majority, however, flexion is necessary, and a Thomas' knee splint with flexion attachment bent to an angle of 30 deg. (Fig. 81) and extension by means of ice-tong callipers secures the best apposition. If this apparatus is not available the limb must be fixed on a double-inclined plane, so constructed that the angle of flexion can be adjusted to meet the requirements of the individual case (Fig. 70).



Hodgen's splint, bent nearly to a right angle, may also be employed.

A careful watch must be kept on the circulation of the limb during the first few days, lest it be interfered with by the pressure of the apparatus.

In a considerable number of cases these means of retaining the fragments in apposition prove ineffectual, and it is necessary to have recourse to operative measures for mechanical fixation. Division of the tendo calcaneus (Achillis) is not to be recommended as a means of combating the backward tilting of the distal fragment.

In all cases the retentive apparatus must be worn for about four weeks, after which the limb is flexed over a pillow; but massage and movement should be employed as soon as possible, as persistent stiffness of the knee is one of the most troublesome sequelae of these injuries.

Compound and complicated fractures are dealt with on the general principles governing the treatment of such injuries. Amputation may become necessary should gangrene ensue from injury to the popliteal vessels, or if infective complications threaten the life of the patient.

Operative interference may be called for to rectify deformities resulting from mal-union.

The T- or Y-shaped fracture is, as a rule, produced by direct violence, the force first breaking the bone above the condyles and then causing the proximal fragment to penetrate the distal and split it up into two or more pieces. The fracture implicates the articular surface, and the main fissure is usually through the inter-condylar notch; the lower end of the bone is sometimes severely comminuted.

The knee is broadened, and pain and crepitus are readily elicited on moving the condyles upon one another or on pressing them together. On moving the patella transversely, it may be felt to hitch against the edge of one or other of the fragments. The shortening may amount to one or two inches.

The treatment is carried out on the same lines as in supra-condylar fracture, but as the joint is implicated there is greater risk of subsequent impairment of its functions.

Separation of the lower epiphysis is a comparatively common injury. It is seldom pure, a portion of the diaphysis usually being broken off and remaining attached to the epiphysis. It occurs usually in boys between the ages of thirteen and eighteen, from severe violence such as results from the limb being caught between the spokes of a revolving wheel, or from hyper-extension of the knee. It has also been produced in attempting forcibly to rectify knock-knee and other deformities in this region, and in making traction on the limb to correct deformities following recovery from tuberculous disease of the knee. As a rule, there is little displacement of the loose epiphysis, but it may pass in any direction, forward being much the most common (Fig. 82), and when displaced it is difficult to reduce and to maintain in position. The age of the patient, the mode of injury, the finding of the smooth broad end of the diaphysis in the popliteal space or on the front of the thigh, according to the displacement, usually serve to establish the diagnosis. The X-rays afford reliable information as to the position of the fragments. Pressure on the popliteal vessels is a serious aggravation of the injury, and adds greatly to the difficulties of treatment.



The treatment is the same as for supra-condylar fracture, but, owing to the serious disability that follows on incomplete reduction, it may be necessary to have recourse to operation. After an epiphysial separation, the growth of the limb is sometimes, although not always, interfered with.

Either condyle may be broken off without the continuity of the shaft being interrupted, by a direct blow or fall on the knee, or by violent twisting of the leg. The separated condyle may not be displaced, or it may be pushed upwards or rotated on its transverse axis.

There is broadening of the knee but no shortening of the thigh, and the ecchymosis, crepitus, and pain are localised to the affected side of the joint; the knee can usually be moved towards the injured side in a way that is characteristic. If allowed to unite with the condyle displaced, the articular surface is oblique and bow- or knock-knee results.

If there is difficulty in replacing the broken condyle and maintaining it in position, it may be fixed by means of a steel nail inserted through the skin.

FRACTURE OF THE UPPER END OF THE TIBIA

Fracture of the head of the tibia is a comparatively rare injury. It may result from a direct blow, such as the kick of a horse, or from indirect forms of violence, and the line of fracture may be transverse or oblique. Occasionally the distal fragment is impacted into the proximal and comminutes it. In oblique fracture a gliding displacement is liable to occur and cause bow- or knock-knee. Transverse fracture of the head of the fibula sometimes accompanies fracture of the head of the tibia, and there is always considerable effusion into the knee-joint. One or other of the condyles may be chipped off by forcible adduction or abduction at the knee.



The ordinary clinical features of fracture are well marked, and the diagnosis is easy. From some unexplained cause this fracture may take a long time, sometimes several months, to consolidate.

Separation of the upper epiphysis of the tibia, which includes the tongue-like process for the tubercle and the facet for the fibula, is also rare. It usually occurs between the ages of three and nine. The displacement of the epiphysis is almost always forward or lateral, and is accompanied by the usual signs of such lesions. The growth of the limb is sometimes arrested, and shortening and angular deformity may result.

Treatment.—After reduction under an anaesthetic these fractures are usually satisfactorily treated in a box splint (Fig. 91), carried sufficiently high to control the knee-joint. When the head of the tibia is comminuted or split obliquely, weight-extension—direct from the bone, the ice-tong callipers grasping the malleoli or the calcaneus—may be used. Massage and movement are employed from the outset.

Avulsion of the tuberosity of the tibia occasionally occurs in youths, from violent contraction of the quadriceps—as in jumping. The limb is at once rendered powerless; the osseous nodule can be felt, and on moving it crepitus is elicited.

This is best treated by pegging the tuberosity in position, and fixing the extended limb on an inclined plane to relax the quadriceps muscle.

In young, athletic subjects, the tongue-like process of the epiphysis (Fig. 85), into which the ligamentum patellae is inserted, may be partly or completely torn away, giving rise to localised swelling, and pain which is aggravated by any muscular effort—Schlatter's disease or "rugby knee." It has been frequently observed in cadets as a result of kneeling at drill. The treatment consists in rest and massage, but the symptoms are slow to disappear.



The condition is liable to be mistaken for some chronic inflammatory condition of the bone, such as tubercle, unless an X-ray examination is made.

The upper end of the fibula is seldom broken alone. The chief clinical interest of this fracture lies in the fact that it may implicate the common peroneal nerve, and cause drop-foot.

DISLOCATIONS OF THE KNEE

Dislocation of the knee is a rare injury, and occurs as a result of extreme degrees of violence, especially of a wrenching or twisting character.

Rupture of the popliteal vessels, or pressure exerted on them by the displaced bones, may lead to gangrene of the limb, and necessitate amputation. The common peroneal nerve is frequently damaged. When the lesion is compound, also, amputation may become necessary on account of infective complications.

The varieties of dislocation are named in terms of the direction in which the tibia passes: forward, backward, medial, and lateral.

Dislocation forward is the most common variety, and results from sudden hyper-extension of the knee, tearing the collateral and cruciate ligaments. The leg remains fully extended, and lies on a plane anterior to that of the thigh. The condyles of the femur are palpable posteriorly, and the skin is tightly stretched over them, or may even be torn, rendering the dislocation compound. The patella is projected forward, the quadriceps tendon is lax, and the skin over it is thrown into transverse folds. The limb is shortened by two or three inches.

Dislocation backward is usually due to a direct blow driving one of the bones past the other. The leg remains hyper-extended, the head of the tibia occupies the popliteal space, while the lower end of the femur projects forward with the patella either in front or to one side of it.

The medial and lateral dislocations are generally incomplete, and are liable to be mistaken for separation of the lower epiphysis of the femur. When the tibia passes medially, the lateral condyle of the femur forms a prominence, and there is a depression below it. The head of the tibia projects on the medial side, and the medial condyle is in a depression.

When the tibia is displaced laterally, the relative position of the prominences and depressions is reversed.

Treatment.—In dislocations of the knee no special manipulations are necessary to restore the displaced bone to its place, and reduction is not accompanied by a distinct snap.

If, while the patient is fully anaesthetised, traction is made on the leg and counter-traction on the thigh with the knee in the flexed position, the bones can usually be replaced by manipulation.

After reduction has been effected, in antero-posterior dislocations, the limb should be flexed and placed on a pillow, massage and movement being employed from the first. The patient is usually able to walk within a month.

In medial and lateral dislocations there is at first considerable tendency to re-displacement, and it is therefore necessary to secure the joint in a box splint, specially padded, for about fourteen days, massage being employed from the first, and movement commenced when the splint is removed. It is usually about six weeks before the patient can use the limb with freedom.

In compound dislocations, and in those complicated by injury to the popliteal vessels, the question of amputation may have to be considered.

Dislocation of the Superior Tibio-Fibular Articulation.—This joint may be dislocated by twisting forms of violence applied to the foot or leg, or by forcible contraction of the biceps muscle. The displacement may be forward or backward, and the head of the fibula can be felt in its new position with the prominent tendon of the biceps attached to it. The movements of the knee are quite free, but the patient is unable to walk on account of pain. Reduction and retention are, as a rule, easy, and the ultimate result satisfactory. We have frequently met with this injury accompanying compound fractures of both bones of the leg resulting from railway and similar accidents.

By applying direct pressure over the displaced bone with the knee flexed, the dislocation is easily reduced. It is kept in position by a firm bandage or a light rigid splint.

Total Dislocation of Fibula.—Very rarely the fibula is separated from the tibia at both ends and displaced upwards. Bennett of Dublin has pointed out that in some persons the upper end of the fibula does not reach the facet on the tibia—a condition which might be mistaken for a dislocation.

INJURIES OF THE SEMILUNAR MENISCI

The semilunar menisci are two crescentic plates of white fibro-cartilage, which lie upon the upper end of the tibia, and serve to deepen the articular surface for the condyles of the femur. Each cartilage is firmly attached to the tibia by its anterior and posterior ends, and, through the medium of the coronary ligaments, is loosely attached along its peripheral, convex edge to the head of the tibia, the medial meniscus being connected also to the capsular ligament of the joint. The tendon of the popliteus muscle intervenes between the lateral meniscus and the capsule. The central, concave edges of the menisci are thin and unattached.

The cartilages enjoy a limited range of movement within the joint, passing backwards during flexion, and forwards again when the limb is extended; under normal conditions the lateral moves more freely than the medial. While the limb is partly flexed, a slight degree of rotation of the leg at the knee is possible, and during this movement the cartilages glide from side to side, and the tibia rotates below them.

Any abnormal laxity of the ligaments of the joint may render the cartilages unduly mobile, so that they are liable to be displaced from comparatively slight causes, and when so displaced it is not uncommon for one or other to be torn by being nipped between the femur and the tibia. It is convenient to consider these "internal derangements of the knee-joint" separately, according to whether the meniscus is merely abnormally mobile, or is actually torn.

Mobile Meniscus—Displacement of Medial Semilunar Cartilage (Fig. 86).—The medial meniscus exhibits undue mobility much more frequently than the lateral, and the condition is usually met with in adult males who engage in athletics, or who follow an employment which entails working in a kneeling or squatting position for long periods, with the toes turned outwards—for example, coal-miners. The tibial collateral ligament, and through it the coronary ligament, are thus gradually stretched, so that the cartilage becomes less securely anchored, and is rendered liable to be displaced towards the centre of the joint during some sudden movement which combines flexion of the knee with medial rotation of the femur upon the tibia, as, for example, in rising quickly from a squatting position, or turning rapidly and pushing off with the foot, in the course of some game such as football or tennis. It may occur also from tripping on a loose stone or slipping off the kerbstone.



What actually happens when the meniscus is displaced would appear to be, that the combined flexion and abduction of the knee opens up the medial side of the joint by separating the medial condyles of the femur and tibia, and that the medial meniscus in its movement backward during flexion slips under the femoral condyle and is caught between it and the tibia. It may even slip past the condyle and into the intercondyloid notch, and come to lie against the cruciate ligaments.

The mechanism by which this lesion is produced doubtless explains the greater frequency with which the left knee is affected, as most sudden movements are made from right to left, thus throwing the strain upon the left knee.

Clinical Features.—When seen immediately after the accident, the patient usually gives the history that while making a sudden movement he was seized with an intense sickening pain in the knee, accompanied, it may be, by a sensation of something giving way with a distinct crack, and followed by locking of the joint. He may fall to the ground and be unable to rise. On examination, the knee is found to be fixed in a slightly flexed position; and while the surgeon may be able to carry out movements of flexion to a considerable extent without increasing the pain, any attempt to extend the joint completely is extremely painful. Tenderness may be elicited on making pressure to the medial side of the ligamentum patellae in the groove between the femur and the tibia, but the meniscus cannot be recognised by palpation. Considerable effusion rapidly takes place into the synovial cavity.

The condition is liable to be mistaken for a sprain of the joint, particularly one implicating the tibial collateral ligament, but whereas in the lesion of the meniscus the maximum tenderness is in the interval between the bones, in the sprain of the ligament the maximum tenderness is over its attachment to the bone, usually the tuberosity of the tibia.

Treatment.—To reduce the displacement, the patient is placed on a couch, and, after the knee is fully flexed, the leg is rotated laterally and abducted, to separate the medial femoral condyle from the tibia, and while the rotation and abduction are maintained the leg is quickly extended. The return of the meniscus to its place is sometimes attended with a distinct snap, but in other cases reduction is only recognised to have taken place by the fact that the joint can be completely extended without causing pain.

Alternate flexion and extension combined with rotatory movements is sometimes successful. Several attempts are often necessary, and a general anaesthetic may be called for. After reduction, the limb is fixed with sand-bags, and massage and movement are employed to get rid of effusion, care being taken that no rotatory movement at the knee is permitted. Rest and support are necessary to allow of repair of the torn ligaments, and when the patient begins to use the limb he must be careful to avoid movements which throw strain on the damaged ligaments.

In a considerable proportion of cases no recurrence takes place, and in the course of a month or two the patient is able to resume an active life with a perfectly useful joint. In other cases there is a tendency to recurrence of the displacement.

Recurrent Displacement.—In cases of recurrent displacement, each attack is accompanied by symptoms similar in kind to those above described, but less severe, and the patient usually learns to carry out some manipulation by which he is able to return the meniscus into position. He seeks advice with a view to having something done to prevent displacement occurring, and to restore the stability of the joint, which, in many cases, is impaired, preventing him following his occupation. There persists a variable amount of fluid in the joint, the ligaments are stretched and slack, and the quadriceps muscle is markedly wasted.

The symptoms closely resemble those of a "loose body," and it is often difficult to differentiate between them. In the case of a body free in the cavity of the joint, the site of the pain varies in different attacks, and the body can sometimes be palpated. Loose bodies wholly or partly composed of bone may be identified with the X-rays.

Attempts may be made to retain the meniscus in position by pads, bandages, or other forms of apparatus, so arranged as to prevent rotation and side-to-side movement at the knee. In the majority of cases, however, the best results are obtained by opening the joint and excising the meniscus in whole or in part, as may be necessary.

The limb is flexed on a splint until the wound has healed, after which massage should be employed and movement of the joint commenced. At the end of two or three weeks the patient is allowed up, wearing an elastic bandage. In most cases the use of the joint is completely regained in from four to six weeks. As an indication of the perfect recovery of the functions of the joint after removal of the meniscus, professional football players are often able to resume their occupation.

Displacement of the lateral meniscus is comparatively rare. It is in every way comparable to displacement of the medial meniscus, and is treated on the same lines.

Torn or Lacerated Meniscus.—In a large proportion of cases of displaced meniscus in which the condition assumes the recurrent type, it is found, on opening the joint, that, in addition to being unduly mobile, the meniscus is torn or lacerated. The experience of surgeons varies regarding the nature of the laceration. In our experience the most common form is a longitudinal split, whereby a portion of the inner edge of the cartilage is separated from the rest and projects as a tag towards the centre of the joint (Fig. 86). As a rule, it is the anterior end that is torn, less frequently the posterior end. Sometimes the meniscus is split from end to end, the outer crescent remaining in position, while the inner crescent passes in between the condyles and lies curled up against the cruciate ligaments. Occasionally the anterior end is torn from its attachment to the tibia, less frequently the posterior end. In one case we found the meniscus separated at both ends and lying between the bones and the capsule.

The clinical features are similar to those of mobile meniscus with displacement, and as a rule the exact nature of the lesion is only discovered after opening the joint.

The treatment consists in excising the loose tag or the whole meniscus, according to circumstances. The recovery of function is usually complete. It is not advisable to attempt to stitch the torn portion in position.

Rupture of the Cruciate Ligaments.—A few cases have been recorded in which, as a result of severe twisting forms of violence, the cruciate ligaments have been torn from their attachments, leaving the joint loose and unstable, so that the tibia and the femur could be moved from side to side on one another. When the disability persists, the joint may be opened and the ligaments sutured in position (Mayo Robson).

Sprains of the knee are comparatively common as a result of sudden twisting or wrenching of the joint. In addition to the stretching or tearing of ligaments, there is usually a considerable effusion of fluid into the synovial cavity, and examination with the X-rays occasionally reveals that a portion of bone has been torn away with the ligament—sprain-fracture. The swelling fills up the hollows on either side of the patella, and extends for some distance in the synovial pouch underneath the quadriceps. The patella is raised from the front of the femur by the collection of fluid in the joint—"floating patella"—and, if firmly pressed upon, it may be made to rap against the trochlear surface.

A sprain is to be diagnosed from separation of one or other of the adjacent epiphyses, fracture involving the articular ends of the bones, and displacement of the semilunar menisci. On account of the swelling, which obscures the outline of the part, the differential diagnosis is often difficult, but as the swelling goes down under massage it becomes easier. Chief reliance is to be placed upon the bony points retaining their normal relationships, and upon the fact that the points of maximum tenderness are over the attachments of one or other of the collateral ligaments. As the tibial collateral ligament suffers most frequently, the most tender spot is usually over its attachment to the medial aspect of the head of the tibia—less frequently over the medial condyle of the femur.

Unless efficiently treated, a sprain of the knee is liable to result in weakness and instability of the joint from stretching of the ligaments, and this is often associated with effusion of fluid in the synovial cavity (traumatic hydrops). This is more likely to occur if the joint is repeatedly subjected to slight degrees of violence, such as are liable to occur in football or other athletic exercises—hence the name "footballer's knee" sometimes applied to the condition.

A further cause of disability, following upon sprains of the knee, is wasting of the quadriceps muscle. The stability of the joint, whenever the position of full extension has been departed from, is largely dependent upon its capacity of controlling the amount of flexion, notably in descending a stair or in walking on uneven ground, hence it is that with a wasted quadriceps there is increasing liability to a repetition of the sprain. With each repetition of the sprain, there is an addition to the fluid in the joint, stretching of ligaments, and further wasting of the quadriceps. A form of vicious circle is established in which there is at the same time increased liability to sprain and diminished capacity of recovering from it. Even after the repair of the damaged ligament or the removal of the mobile or torn meniscus, wasting of the quadriceps remains a source of weakness and disability and calls for treatment by massage and electricity.

Treatment.—In recent and severe cases the patient must be confined to bed, and firm pressure applied over the joint by means of cotton wool and a bandage. This may be removed once or twice a day to admit of the joint being douched, and at the same time it should be massaged and moved to promote absorption of the effusion and prevent the formation of adhesions.

Chronic effusion into the joint is most rapidly got rid of by rest and blistering. If the patient is unable to lie up, massage should be systematically employed, and a firm elastic bandage worn. A patient who has once had a severe sprain of the knee, or who has developed the condition of "footballer's knee," must give up violent forms of exercise which expose him to further injuries, otherwise the condition is liable to be aggravated and to result in permanent impairment of the stability of the joint.

INJURIES OF THE PATELLA

Fracture of the patella is a comparatively common injury in adult males. Most frequently it is due to muscular action the patella being snapped across the lower end of the femur by a sudden and forcible contraction of the quadriceps extensor muscle while the limb is partly flexed—as, for example, in the attempt to avoid falling backward. The bone is then broken as one breaks a stick by bending it across the knee, and the line of fracture, which is transverse or slightly oblique, crosses the bone a little below its middle. Fractures produced in this way are almost never compound.



The degree of displacement of the fragments depends upon the extent to which the expansion of the quadriceps tendon is lacerated. As a rule, it is but slightly torn, so that the separation of the fragments does not exceed an inch. In other cases it is widely torn, and the contraction of the quadriceps muscle is then able to separate the fragments by three or four inches, and sometimes causes tilting of the upper fragment. The blood effused into the joint tends still further to increase the separation. As the periosteum is usually torn at a level lower than the fracture, its free margin hangs as a fringe from the proximal fragment, and by getting between the broken ends may form a barrier to osseous union (Macewen).

Clinical Features.—Immediately the bone breaks, the patient falls, and he is unable to rise again, as the limb is at once rendered useless, and in attempting to do so we have known him to fracture the patella of the other limb. The power of extending the limb is lost, and the patient is unable to lift his foot off the ground. The knee-joint is filled with blood and synovia, which usually extend into the bursa under the quadriceps. The two fragments can be detected, separated by an interval which admits of the finger being placed between them, and which is increased on flexing the knee. On relaxing the quadriceps, the fragments may be approximated more or less completely.

Prognosis.—In cases with little displacement, if the fragments have been kept in perfect apposition, osseous union may take place, but in the great majority of cases the union is fibrous. The shortening of the quadriceps and the gradual stretching and thinning of the connecting fibrous band may allow of further separation of the fragments (Fig. 88), which to a variable extent interferes with the stability and functions of the limb. The proximal fragment sometimes becomes attached to the front of the femur, and moves with it, and the fibrous band between the two fragments gradually becomes stretched. After bony union has occurred, it is not uncommon for the patella to be fractured again by a fall within a month or two of the original accident.



Treatment.—It is probably true that the best functional results are most speedily obtained by operative measures. The laceration of the aponeurosis of the quadriceps, the tilting of the fragments, and the interposition of the torn periosteum between them, can in no other way be rectified with certainty. The operation, however, should only be undertaken by those who are familiar with wound technique, and who have the means at their disposal for carrying it out. Operative treatment is specially indicated in young subjects who lead an active life, and in labouring men, particularly those who follow dangerous employments necessitating stability of the knee.

As soon as the wound is healed,—in a week or ten days,—massage and movement of the limb are commenced, and the patient is encouraged to move his limb in bed. At the end of another week he may be allowed up with sticks or crutches.

Non-operative Treatment.—In the majority of cases occurring in patients who do not follow a laborious occupation or otherwise lead an active life, a satisfactory result can be obtained without having recourse to operation. We have reason to be satisfied with the following method: the patient is kept in bed for a few days, the injured region being supported on a pillow and massaged daily, and the patella moved from side to side as a whole to prevent adhesion to the femur. About the fourth day he is allowed to get about with crutches. As osseous union of the fragments is not essential to a good functional result, and as fibrous union does not necessarily entail any material interference with the usefulness of the limb, no attempt need be made to approximate the fragments, but every effort must be made to maintain the function of the quadriceps muscle and the mobility of the joint.

If it is desired to bring the fragments into contact and to secure osseous union, the limb should be placed upon an inclined plane to relax the quadriceps muscle, and means taken to arrest effusion and to diminish the swelling by systematic massage and a supporting bandage. When, in the course of a few days, this has been accomplished, the attempt is made to approximate the fragments, by fixing a large horseshoe-shaped piece of adhesive plaster to the front of the thigh, embracing the proximal fragment. Extension is made upon this by means of rubber tubing, which is fixed to the foot-piece of the splint. The bandage which binds the limb to the splint should make upward pressure on the distal fragment, or this may be done by a special piece of adhesive plaster with elastic tubing pulling in an upward direction.

The retentive apparatus is kept on for about three weeks, and a rigid, but easily removable, apparatus is thereafter applied, and the patient allowed up on crutches, the limb being massaged and exercised daily to improve the tone of the muscles.

When the fracture is caused by direct violence, such as a fall on the knee or the kick of a horse, it may be transverse, oblique, or vertical, but in many cases it is stellate, the bone being broken into several irregular pieces. These comminuted fractures are frequently compound. In transverse and oblique fractures, the displacement depends upon the same causes as in fracture by muscular action. In vertical and stellate fractures, unless the knee has been forcibly flexed after the bone has been broken, there is little or no displacement. The treatment is governed by the same considerations as in fractures by muscular action.

Old-standing Fracture.—As fibrous union, even with an interval of several inches between the fragments, is not incompatible with a useful limb, it is not often necessary to operate for this condition, but when the usefulness of the limb is seriously impaired, operative treatment is indicated. The operation is carried out on the same lines as for recent fracture, the ends of the bones being rawed and adhesions divided. When the proximal fragment has become attached to the femur, it should be separated and a layer of fascia interposed; it is sometimes necessary to lengthen the quadriceps muscle by making a number of V-shaped incisions through its substance; or a flap may be turned down from the rectus and stitched to the patella and the ligamentum patellae.

When operative treatment is contra-indicated, the patient should be fitted with a firm apparatus which will limit flexion of the knee and support the fragments.

Dislocation of the patella is rare. It results from exaggerated muscular movements when the limb is in the fully extended position, or from a blow on one or other edge of the bone. Laxity of the ligaments and knock-knee are predisposing factors. It is sometimes associated with fracture of the edge of the trochlear surface, which renders retention in position difficult.

The lateral is the most common variety—the medial being rare. Either may be complete or incomplete. Sometimes the bone is rotated so that its edge rests on the front of the femur—vertical dislocation; and in a few cases it has been completely turned round, so that the articular surface is directed forwards.

Clinical Features.—The joint is fixed, usually in a position of slight flexion, and the displaced patella can readily be palpated. The deformity is a striking one, and at first sight suggests a much more serious injury. Although easily reduced, the dislocation is liable to recur.

To effect reduction, the quadriceps must be thoroughly relaxed by extending the leg upon the thigh and flexing the thigh upon the pelvis; the patella is then tilted by making firm pressure on that edge which lies farthest from the middle of the joint, and at the same time pushing towards the middle line. The limb is placed on a posterior splint, and firm elastic pressure made on the joint to prevent or diminish effusion. Massage and movement are carried out from the first.

As the displacement is liable to recur, the patient should wear a firm elastic bandage or a strong knee-cap.

Permanent and recurrent dislocation of the patella will be described later.

FRACTURE OF THE BONES OF THE LEG

The bones of the leg may be broken together or separately.

Fracture of both Bones.—The features of this injury depend to a large extent upon the nature of the violence producing it. In fracture by direct violence, such as the passage of a wheel over the limb or a severe blow, the bones give way at the point of impact, and the line of fracture tends to be transverse, both bones being broken at the same level (Fig. 89). There is little or no displacement, and such as there is is angular, and is determined by the direction of the fracturing force.



When the violence is indirect, as from a fall on the feet, or a twist of the leg, the tibia usually gives way at the junction of its lower and middle thirds, and the fibula at a higher level (Fig. 90). Torsion of the tibia is probably the most important factor in the production of the fracture, the distal fragment being fixed by the pressure of the foot upon the ground, while the proximal fragment is rotated by the impetus of the body. Both fractures are usually oblique—that in the tibia running from above downward, forward, and medially, and it is generally found that the obliquity of the fibular fracture corresponds with that in the tibia.



There is usually considerable displacement, the weight of the lower portion of the limb causing it to fall backwards and to roll away from the middle line, and the traction of the calf muscles pulling up the heel and pointing the toes. The proximal fragment forms a projection on the front of the limb.

On account of the superficial position of the tibia and the pointed character of the fragments, this fracture is frequently rendered compound by the bone being forced through the skin. The projecting piece of bone is usually the distal end of the proximal fragment. This fracture is often comminuted. It has been observed that when the line of fracture forms the letter V on the subcutaneous surface of the tibia, there is invariably a fissure passing down along the back of the bone into the ankle-joint—a complication which adds to the risk of subsequent stiffness and impaired usefulness of the limb. Apart from this, the ankle is usually sprained in fractures by indirect violence, and we have frequently found the superior tibio-fibular articulation torn open in severe fractures of both bones of the leg from indirect violence.

Clinical Features.—The tibial fracture is readily recognised by detecting an irregularity on running the fingers along the crest of the shin, and at this point abnormal mobility, tenderness, and crepitus can usually be elicited. It is often difficult to detect the fibular fracture, and it is not always advisable to attempt to do so, especially if the manipulations cause pain or tend to increase the displacement. The condition of the fibula is usually to be inferred by noting the amount of displacement and the extent of mobility of the tibial fragments. Not infrequently the seat of fracture may be recognised by locating a point at which pain is elicited on making pressure over the bone at a distance—pain on distal pressure.

On account of the close connection of the skin to the periosteum on the subcutaneous aspect of the tibia, the tension caused by extravasated blood is often extreme; blisters frequently form over the area of ecchymosis, and when these become infected, sloughing of the skin may take place and the fracture thus be rendered compound.

The vessels and nerves of the leg are seldom seriously damaged.

Treatment.—If there is marked displacement, reduction is most satisfactorily accomplished under anaesthesia. Traction is made upon the foot and the fragments are manipulated into position, the pointing of the toes and the outward rotation of the foot being at the same time corrected. The normal outline of the foot in relation to the leg is restored when the ball of the great toe, the medial malleolus, and the medial edge of the patella are in the same vertical plane. As in other fractures of the lower extremity, the limb should be placed in the natural position of slight eversion: not with the toes pointing straight forward.

The retentive apparatus to be applied depends upon the tendency to re-displacement, the degree of swelling, and the extent of the damage to the skin.

In the average case, the leg is supported between sand-bags, and massage and movements are employed from the outset. When there is a tendency to re-displacement, the limb may be immediately enclosed in a rigid apparatus, such as lateral poroplastic splints retained in position by an elastic bandage, or a Cline's splint, which can readily be removed to admit of massage. When the fracture is in the lower third of the leg, the ambulatory splint gives excellent results, and is of special service in hospital practice (Fig. 95).

As an emergency appliance, for example for purposes of transport, the box splint (Fig. 91) is simple and efficient. We have not found it effectual in controlling the fragments, particularly in oblique fractures, and it requires constant supervision and readjustment. It consists of two pieces of wood extending from above the knee to an inch or two beyond the sole, and a little broader than the maximum diameter of the leg. These are rolled into the opposite ends of a folded sheet, so as to form two sides of a box, of which the sheet constitutes a third side. It is found advantageous to insert another board, fitted with a foot-piece, between the folds of the sheet forming the third side of the box, to add to the rigidity of the splint, and to aid in controlling the foot. By folding one side of the sheet somewhat obliquely, the box is made a little wider at the knee than at the ankle, and so fits the limb more accurately.



The limb is placed in this box, the sides of which have been carefully padded. Ring pads are applied to take pressure off the condyles, the head of the fibula, the malleoli, and the prominence of the heel, and a large supporting pad is placed behind the tendo calcaneus. A folded towel is laid over the front of the leg, forming a lid to the box, and the whole is bound to the limb by three slip-knots. Finally, the foot is fixed at right angles to the leg and slightly abducted by a figure-of-eight bandage or a piece of elastic webbing. Sand-bags placed alongside serve to steady the limb. In fractures of the lower third of the leg, the box splint may stop short of the knee and the limb may then be suspended in a Salter's cradle, which allows the patient to move about more freely in bed.



To prevent shortening in oblique fractures and in those near the ankle-joint, where it is often difficult to control the lower fragment, extension, applied by weight and pulley, or through a Thomas' knee splint, may be of service. The strapping may be applied only to the distal fragment, but we prefer to carry it to the upper third of the leg. If the overriding of the fragments persists, extension may be taken directly from the bone, the ice-tong callipers gripping the malleoli or the calcaneus.

When the skin is damaged, as it so frequently is on the medial aspect of the tibia, means must be taken to prevent infection.

Massage is carried out daily, and, to prevent stiffness, the ankle is moved from the first. In the course of three weeks, lateral poroplastic splints retained by an elastic bandage may be substituted, and the patient allowed up on crutches. In simple fractures without displacement, union is usually complete in from six to eight weeks, but when the fracture is oblique, comminuted, or compound, union is often delayed, and the functions of the limb may not be fully regained for three or even four months after the accident.

Operative Treatment.—When overriding cannot otherwise be corrected, it is advisable to replace the fragments by operation. A curved incision with its convexity backward is made over the medial side of the tibia, exposing the fragments, which are then levered into position and if necessary plated or otherwise fixed according to circumstances. It is seldom necessary to deal separately with the fibula. A box splint is applied till the wound has healed, after which a poroplastic splint is substituted and massage commenced.

We do not share in the dissatisfaction expressed by some surgeons, notably Arbuthnot Lane, as to the results obtained by non-operative means in the common fractures of the leg, and do not recommend a systematic resort to operative treatment.

Un-united fracture of the bones of the leg is sometimes met with. It is treated on the same lines as in other situations, but may prove extremely intractable, especially in children, in whom, indeed, it is sometimes incurable.

Mal-union, on account of the disability it entails, may call for operative treatment in the form of osteotomy of one or both bones.

Compound fractures of the leg are common, and are treated on the lines already laid down for the treatment of compound fractures in general (p. 25).

Fracture of the tibia alone, when due to direct violence, is usually transverse, there is little displacement, and as the fibula retains the fragments in position, union usually takes place rapidly and without deformity. Oblique and spiral fractures result from indirect violence.

Fracture of the fibula alone may result from direct violence, and, on account of the support given by the tibia, is usually unattended by displacement. Bennett of Dublin has pointed out that it is common to meet with an oblique fracture of the upper third of the fibula as the result of an outward twist of the ankle while the foot is extended. It is characterised by pain localised at the seat of the break, on moving the foot in such a way as to bring the talus to bear against the fibula. Local pressure also may make the fibula yield and may elicit crepitus. In some cases this fracture is associated with sprain of the ankle-joint. It is often overlooked, and from want of proper treatment may result in prolonged impairment of usefulness.

Fractures of the tibia or fibula alone are treated on the same lines as fractures of both bones, and splints are rarely necessary. The ambulant method is useful in these cases (Fig. 95).



CHAPTER VIII

INJURIES IN REGION OF ANKLE AND FOOT

Surgical Anatomy—FRACTURES: Pott's fracture; Converse of Pott's fracture; Separation of lower epiphysis; Fracture of talus; Fracture of calcaneus; Fractures of other tarsal bones; Fractures of metatarsal bones; Fractures of phalanges—DISLOCATIONS: Of ankle joint; Of inferior tibio-fibular joint; Complete dislocation of talus; Sub-taloid dislocation; Medio-tarsal dislocation; Tarso-metatarsal dislocation; Dislocations of toes.

The fractures in this region include Pott's fracture, and its converse; separation of the lower epiphysis of the tibia; fractures of the talus, calcaneus, and other tarsal bones; and fractures of the metatarsals and phalanges. Various dislocations also occur, the most important being those of the ankle joint, of the talus, and the sub-taloid dislocation.

Surgical Anatomy.—For the study of injuries in the region of the ankle-joint it is of importance to define the terms employed in describing the movements of the foot. Thus by flexion or dorsiflexion is meant that movement which approximates the dorsum of the foot to the front of the leg; while extension or plantar flexion means the drawing up of the heel so that the toes are pointed. In inversion the medial edge of the foot is drawn up so that the sole looks towards the middle line of the body, an attitude which is analogous to supination of the hand. In eversion the lateral edge of the foot is drawn up, the sole looking away from the middle line—analogous to pronation of the hand. Adduction indicates the rotation of the foot so that the toes are turned towards the middle line of the body; while in abduction the toes are turned away from the middle line.

The most prominent bony landmarks in the region of the ankle are the two malleoli, the lateral lying slightly farther back, and about half an inch lower than the medial. On the medial side of the foot from behind forward may be felt the medial process (internal tuberosity) of the calcaneus; the sustentaculum tali, which lies about 1 inch vertically below the tip of the malleolus; the tubercle of the navicular, about 1 inch in front of the malleolus, and at a slightly lower level; the first (internal) cuneiform, and the base, shaft, and head of the first metatarsal.

On the lateral side may be recognised the lateral process (external tuberosity) of the calcaneus; the trochlear process (peroneal tubercle) on the same bone; the cuboid; and the prominent base of the fifth metatarsal.

The talo-navicular joint lies immediately behind the tuberosity of the navicular, and a line drawn straight across the foot at this level passes over the calcaneo-cuboid joint.

The ankle-joint, formed by the articulation of the tibia and fibula with the talus, lies about half an inch above the tip of the medial malleolus, and is so constructed that when the foot is at a right angle with the leg it is only possible to flex and extend the joint. When the toes are pointed, however, slight side-to-side and rotatory movements are possible. The chief seat of side-to-side movement of the foot is at the talo-navicular and calcaneo-cuboid articulations—"the mid-tarsal or Chopart's joint."

The ankle-joint owes its strength chiefly to the malleoli and the collateral ligaments, and to the inferior tibio-fibular ligaments, which bind together the lower ends of the bones of the leg. The numerous tendons passing over the joint on every side also add to its stability.

The synovial membrane of the ankle-joint passes up between the bones of the leg to line the inferior tibio-fibular joint; but it is distinct from that of the intertarsal joints, which communicate with one another in a complicated manner. The epiphysial cartilage at the lower end of the fibula lies on the level of the talo-tibial articulation, while that of the tibia is about half an inch higher (Fig. 93).



FRACTURES IN THE REGION OF THE ANKLE

Pott's Fracture.—It must be understood that various lesions occurring in the region of the ankle-joint are included under the clinical term "Pott's fracture." Although of a similar nature, and produced by the same forms of violence, these vary considerably in their anatomy and clinical features. They are all the result of combined eversion and abduction of the foot—produced, for example, by slipping off the kerbstone, or by jumping from a height and landing on the medial side of the foot.

When forcible eversion is the chief movement, the tightening of the deltoid (internal lateral) ligament usually tears off the medial malleolus across its base. The talus is then brought to bear on the lateral malleolus, and the force continuing to act, the lower end of the fibula is pressed laterally, and breaks close above the malleolus. The tibio-fibular interosseous ligament may rupture, or the outer portion of the tibia, to which it is attached, may be avulsed. This form is sometimes called Dupuytren's fracture. When the bones are widely separated in Dupuytren's fracture the talus may be forced up between them.

When the movement of abduction predominates, the deltoid ligament is usually ruptured, or the anterior edge or tip of the medial malleolus torn off. The tibio-fibular interosseous ligament usually resists, and an oblique fracture of the fibula 2 or 4 inches above its lower end results.

Clinical Features.—In a considerable proportion of cases—in our experience in the majority—this fracture is not accompanied by any marked deformity of the foot, and the patient is often able to walk after the injury with only a slight limp.

In others, however, the deformity is marked and characteristic (Fig. 94). The foot is everted, its inner side resting on the ground. The medial malleolus is unduly prominent, stretching the skin, which may give way if the patient attempts to walk. The foot, having lost the support of the malleoli, is often displaced backward, and the toes are pointed by the contraction of the calf muscles. There is abnormal mobility—both from side to side and antero-posteriorly—and crepitus may be elicited. The points of tenderness are over the deltoid ligament or medial malleolus, the inferior tibio-fibular joint, and at the seat of fracture of the fibula. Distal pressure over the shaft of the fibula, or on the extreme tip of the malleolus, may elicit pain and crepitus at the seat of fracture. There is usually considerable ecchymosis and swelling in the hollows below and behind the malleoli; and the malleoli appear to be nearer the level of the sole. In Dupuytren's fracture, when the talus passes up between the tibia and fibula, there is great broadening of the ankle.



There is often considerable difficulty in distinguishing a sprain of the ankle from a fracture without displacement, as both forms of injury result from the same kinds of violence, and are rapidly followed by swelling and discoloration of the overlying soft parts. In a sprain, the point of maximum tenderness is over the ligaments and tendon sheaths that have been damaged, while in fracture the site of the break is the most tender spot. The X-rays are useful in the diagnosis of doubtful cases.

Treatment.—In those cases of fracture of the lower end of the fibula in which there is no marked displacement,—and they constitute a considerable proportion,—the limb should be massaged and laid on a pillow between sand-bags, or placed in a box splint for two or three days, until the swelling subsides. Some form of rigid apparatus, such as side poroplastic splints fixed in position with an elastic bandage, which will allow the patient to get about with crutches, is then applied. This is removed daily to permit of massage and movement being carried out—a point of great practical importance, because, if this is neglected, not only does union take place more slowly, but the stiffness of the ankle and oedema of the leg and foot which ensue, prolong the period of the patient's incapacity and endanger the usefulness of the limb.

It is in cases of this kind that the ambulatory method of treatment yields its best results. When, in the course of two or three days, the swelling has subsided, a plaster-of-Paris case (Fig. 95) is applied in such a way that when the patient walks the weight is transmitted from the condyles of the tibia through the plaster case to the ground, no weight being borne by the bones at the seat of fracture. The apparatus is applied as follows: A boracic lint bandage is applied to the limb as far as the knee, and protecting pads or rings of wool are placed over the condyles of the tibia, the head of the fibula, and the malleoli. A pad of wool about 3 inches thick is then placed under the sole and fixed in position by a plaster-of-Paris bandage, which is carried up the limb in the usual way. The case is made specially strong on the sole, around the ankle, up the sides of the leg, and at the bearing-point at the head of the tibia. After the plaster has thoroughly set, the patient is allowed to walk about with a stick, crutches being unnecessary. In the course of three weeks the plaster case may be removed and the limb massaged. It is usually found that the movements of the ankle are scarcely interfered with, and the patient is generally able to resume work within a month of the accident.



When there is marked eversion of the foot, it may be necessary to administer a general anaesthetic to reduce the deformity; and to prevent recurrence of the displacement Dupuytren's splint (Fig. 96) may be used. This splint, which is of the same shape as Liston's long splint, but on a small scale, is applied to the medial side of the leg extending from just below the knee to well beyond the sole of the foot. A large pad is placed in the hollow above the medial malleolus, and it must be thick enough to carry the splint so far from the limb that when the foot is fully inverted it does not touch the splint. The upper end of the splint having been fixed to the leg at the level of the condyles of the tibia, a bandage is applied to correct the eversion of the foot, and at the same time to support the heel, and, as far as possible, to overcome the pointing of the toes. Care must be taken to avoid carrying the turns of this bandage over the seat of fracture. The limb may then be slung in a cradle, or placed on a pillow resting on its lateral side with the knee flexed. In the course of a few days, a poroplastic splint may be substituted and massage commenced.



When backward displacement of the heel is the prominent deformity, Syme's horse-shoe or stirrup splint (Fig. 97) may be employed. It is applied to the anterior aspect of the limb, which is carefully padded to prevent undue pressure on the edge of the shin bone. After the upper end of the splint has been fixed, the heel is pulled forward by a few turns of bandage passed over the prongs at the lower end of the splint. The foot is then inverted and brought up to a right angle by a few supplementary turns of the bandage. In a few days this appliance may be replaced by a poroplastic splint.



Operative Treatment.—If the displacement is not completely corrected by the measures described, the fibular fracture is exposed by a free incision and the fragments are levered into position, and if necessary fixed by lashing with catgut or by other mechanical means.

Mal-union of Pott's fracture may necessitate re-fracture by means of a Jones' wrench, used in the same manner as for club-foot, or the parts are exposed by operation; the bone is divided by means of an osteotome, the foot forcibly inverted, and the limb put up in the same way as in a recent fracture.

The Converse of Pott's Fracture—sometimes called "Pott's Fracture with Inversion."—This injury is fairly common, and results from forcible inversion of the foot. The lateral malleolus is broken across its base, or, in young subjects, along the epiphysial line. The medial malleolus alone may be carried away, or a portion of the broad part of the tibia may accompany it.

The foot is inverted, the heel falls back, and the toes are pointed. In other respects it corresponds to the typical Pott's fracture, and is treated on the same principles. When Dupuytren's splint is required, it is, of course, applied to the lateral side of the leg.

Separation of the lower epiphysis of the tibia is not common. It occurs most frequently between the ages of eleven and eighteen, as a result of forcible eversion or inversion of the foot. It is usually accompanied by fracture of the diaphysis of the fibula (Fig. 98), and is not infrequently compound. When the epiphysis is displaced to one side, the deformity is characteristic. In rare cases the growth of the tibia is arrested, the continued growth of the fibula causing the foot to become inverted. The treatment is the same as for Pott's fracture.



Fracture of the talus usually occurs as a result of a fall from a height, the bone being crushed between the tibia and the calcaneus. It is usually associated with other fractures, and is sometimes impacted, the foot assuming the position of equino-varus. The diagnosis is only to be made by exclusion, or by the use of the Roentgen rays. In interpreting radiograms of injuries in this region, care must be taken not to mistake the os trigonum tarsi for a fracture. In uncomplicated cases, the treatment consists in immobilising the foot and leg in a poroplastic splint and applying massage. In comminuted and in impacted fractures with persistent deformity, complete excision of the bone yields good results.

The calcaneus is most frequently broken by the patient falling from a height and landing on the sole of the foot, and the injury may occur simultaneously in both feet.

The primary fracture is usually longitudinal, passing through the facets for the talus and cuboid, and from this various secondary fissures radiate; the cancellated tissue is much crushed, so that the whole bone is flattened out. In spite of the great comminution, it is often impossible to elicit crepitus, as the fragments are held together by the investing soft parts. In other cases the foot may feel like "a bag of bones." The lesion is often mistaken for a fracture of the lower end of the fibula, or is not diagnosed at all. The chief clinical feature is pain on movement of the foot, or on attempting to walk; the foot appears flat, and the hollows on either side of the tendo Achillis are filled up. In many cases there is a persistent tenderness which delays restoration of function for some months, but the ultimate result is usually satisfactory.

Treatment.—In simple comminuted fractures the patient should be anaesthetised, and the foot moulded into position, care being taken to restore the arch in order to avoid any tendency to flat foot. The foot is supported on a pillow, and to prevent stiffness, massage and movements of the ankle and tarsal joints should be commenced without delay.

Compound fractures confined to the calcaneus may be treated on conservative lines, but if associated with other injuries of the foot they may necessitate amputation.

The tuberosity of the calcaneus, into which the tendo Achillis is inserted, is sometimes separated by forcible contraction of the calf muscles, or from a fall on the ball of the foot. The separated fragment may be pulled up for a distance of 1 or 2 inches, and the rough surface from which it has been torn may be recognisable. The patient may be able to walk immediately after the accident, although with difficulty; or he may have pain for many months.

A good functional result is usually obtained by relaxing the calf muscles and fixing the foot in the position of extreme plantar flexion with the knee flexed, but in some cases it is advisable to peg the fragments, either through the skin or after exposing them by operation.

The other bones of the tarsus are rarely fractured separately. The tuberosity of the navicular is sometimes torn away by violent traction on the ligaments attached to it.

Fractures of the metatarsals and phalanges usually result from direct violence, such as a crush of the foot, in which the soft parts are severely damaged. The use of the Roentgen rays has shown, however, that certain painful conditions in the foot following comparatively slight injuries, such as kicking a stone, are due to a fracture of one of the metatarsals or phalanges.

When simple, these injuries are often overlooked, on account of the difficulty of eliciting the signs of fracture from the swelling which accompanies them. They are best treated in a moulded splint.

Compound fractures are more common, and are to be treated on the same principles as govern such injuries elsewhere.

A fracture of the base of the fifth metatarsal has been described by Sir Robert Jones. It is produced by the patient coming down forcibly on the lateral edge of the foot while the foot is inverted and the heel raised—as, for example, in dancing. There is a localised swelling over the base of the fifth metatarsal, and pain when the patient puts weight on the foot. There is no crepitus or deformity. The fracture is readily recognised by the Roentgen rays. Massage and movement are employed from the first.

DISLOCATIONS IN THE REGION OF THE ANKLE

Dislocation of the Ankle-Joint.—In describing dislocation of the talus from the tibio-fibular socket, the varieties are named according to the direction in which the foot passes—backward, forward, medially, laterally, or upward.

All of them may be complete, but they are more frequently incomplete, and are liable to be rendered compound, either from tearing of the skin at the time of the injury, or by its sloughing later. Although as a rule there is little difficulty in effecting reduction by manipulation, these injuries are liable to be followed by stiffness and impaired usefulness of the joint.

The backward dislocation is the most common, and results from extreme plantar flexion of the foot, as from a fall backwards while the foot is fixed, wedging the talus between the tibia and fibula. The collateral ligaments are torn, and one or both malleoli may be broken, or the posterior part of the articular edge of the tibia chipped off (Fig. 99).



The foot appears shortened, the heel is unduly prominent behind, and the lower ends of the tibia and fibula project in front, sometimes coming through the skin. The tendons around the joint are stretched or torn.

Forward dislocation results from extreme dorsal flexion at the ankle-joint. The foot appears lengthened, the heel is less prominent than normal, and the hollows on each side of the tendo Achillis are obliterated. The talus is felt in front of the tibia, and the malleoli appear to be displaced backwards and to lie nearer the sole.

Medial or lateral dislocation is only possible after fracture of one or both malleoli, and may be looked upon as a complication of these injuries.

In cases in which the interosseous ligament is ruptured, and in severe cases of Dupuytren's fracture, the talus may be driven upwards between the bones of the leg. There is great broadening in the region of the ankle, and the malleoli are unduly prominent under the skin, which is tightly stretched over them. They are also nearer to the sole than normally. The movements of the ankle-joint are lost.

Dislocation of the inferior tibio-fibular joint is exceedingly rare, except in association with fractures of the lower ends of the bones of the leg, particularly Dupuytren's fracture, or with dislocation of the ankle-joint proper.

Treatment of Dislocation of Ankle.—The patient having been anaesthetised, the foot is extended and the knee and hip joints flexed to relax the calf muscles as completely as possible. Traction is then made upon the foot, while counter-extension is applied to the leg, and the bones are manipulated into position. Reduction usually takes place gradually without the characteristic snap which accompanies reduction of most dislocations. It is sometimes necessary to divide the tendo Achillis, particularly in cases of forward dislocation.

When the talus passes upwards between the tibia and fibula, it is sometimes impossible to effect reduction by manipulation, and the best results are then obtained by operation.

The after-treatment consists in keeping the leg on a pillow between sand-bags, and carrying out the usual massage and movement.

In compound dislocations which have become infected, primary amputation may be indicated, but in young and healthy subjects an attempt may be made to save the foot.

Dislocation of the talus from its articulations with the bones of the leg above and the calcaneus and navicular below, is a comparatively common injury, and results from a violent wrench of the foot. It may be incomplete or complete. When the foot is plantar flexed at the moment of injury, the displacement is generally forward with a tendency outward. The talus comes to rest on the third cuneiform and cuboid bones, the foot being abducted, inverted, and displaced medially. In a large proportion of cases the dislocation is compound, more or less of the talus being forced through the skin (Fig. 100).



When the foot is dorsiflexed at the moment of injury the displacement is backward, but this is rare, as is also dislocation to one or other side, and dislocation by rotation, in which the talus is rotated in its socket. In all these injuries the body of the talus loses its normal relationship with the malleoli.

An attempt should be made to reduce the dislocation under anaesthesia, the limb being placed in the same position as for reduction of dislocation of the ankle. While traction is made upon the foot, an assistant presses directly on the displaced bone and endeavours to manipulate it into position. In incomplete dislocations this usually succeeds, but it not infrequently fails in those which are complete, and under these circumstances it may be necessary to chisel through the lateral malleolus to admit of reduction, or to excise the talus. In most cases of compound dislocation also, this bone should be removed.

Sub-taloid Dislocation.—In this dislocation, which results from the same kinds of violence as the last, the talus retains its position in the tibio-fibular socket, and the calcaneus and navicular, with the rest of the foot, are carried away from it. The body of the talus, therefore, maintains its normal relationship with the malleoli—a point of importance in the differential diagnosis between this injury and dislocation of the talus. The displacement is usually incomplete, and the foot may either pass backward and medially, or backward and laterally. When the foot passes backward and medially, the head of the talus projects on the outer part of the dorsum, resting on the cuboid. The dorsum of the foot is shortened, the heel lengthened, the toes adducted, and the medial border of the foot raised. The lateral malleolus is unduly prominent, and reaches nearly to the sole.



In the backward and lateral variety, the medial malleolus and head of the talus project unduly towards the medial side of the foot, which is abducted and everted.

In neither variety is there any mechanical obstacle to movement at the ankle-joint.

The treatment is carried out on the same lines as for dislocation of the talus, reduction being effected without difficulty in most cases. If this fails, as it occasionally does, it may be necessary to excise the talus.

Mid-tarsal or transverse tarsal dislocation—that is, at the talo-navicular and calcaneo-cuboid articulations—is extremely rare. The distal segment of the foot is usually displaced towards the sole; the foot is foreshortened, the malleoli raised from the sole, the arch of the foot is lost, and the first row of tarsal bones projects on the dorsum. The treatment consists in reducing the displacement by manipulation, after which massage and movement are employed.

Tarso-metatarsal Dislocations.—One, several, or all of the metatarsals may be separated from the distal row of tarsal bones—the usual cause being a fall from a horse, the foot being fixed in the stirrup. The bases of the metatarsal bones are displaced laterally and towards the dorsum. The base of the second metatarsal and the first cuneiform are sometimes fractured. Reduction by manipulation is generally easy in dorsal dislocations, but may be difficult when the bones are displaced laterally. This may be due to fragments of bone or soft parts getting between the bones, and may necessitate operative interference. In old-standing dislocations, operation is to be advised only when locomotion is seriously interfered with.

Dislocation of the Toes.—The great toe may be dislocated at its metatarso-phalangeal joint, the base of the proximal phalanx passing towards the dorsum (Fig. 102). Diagnosis and reduction are alike easy.



Inter-phalangeal dislocations are rare and are easily reduced.



CHAPTER IX

DISEASES OF INDIVIDUAL JOINTS

THE SHOULDER-JOINT

The shoulder is seldom the seat of disease, and most affections of the joint are met with in adults. In young subjects, infective processes result chiefly from extension of disease from the upper epiphysial junction of the humerus, which is partly included within the limits of the synovial cavity. The synovial membrane, in addition to lining the capsular ligament, is prolonged down the inter-tubercular (bicipital) groove around the long tendon of the biceps, and pus may escape from the joint by this diverticulum and gravitate down the arm; we have also observed loose bodies of synovial origin in this diverticulum. There is frequently a communication between the joint and the sub-deltoid bursa. There is no attitude characteristic of disease of the shoulder-joint, but the girdle is usually elevated, the upper arm held close to the side and rotated medially, while the elbow is carried a little backwards. In the later stages, the head of the humerus may be drawn upwards and medially towards the coracoid process. Fixation of the shoulder-joint is largely compensated for by movement of the scapula on the thorax, so that when testing for rigidity the scapula should be fixed with one hand while passive movements of the arm are carried out with the other. The deltoid is usually atrophied, allowing the acromion, coracoid, and great tuberosity of the humerus to stand out prominently beneath the skin. Swelling is rarely a prominent feature, except when there is a collection of synovial fluid or of pus in the bursa beneath the deltoid.

Tuberculous Disease is usually met with in young adults, and is more common in the right shoulder. The prominent features are pain, rigidity, and wasting of the deltoid and scapular muscles. The pain is sometimes severe, shooting down the arm and interfering with sleep, and it may be associated with tenderness on pressure over the upper end of the humerus. In cases with carious destruction of the articular surfaces there are starting pains, and the arm is shortened. If a cold abscess forms in the bursa underneath the deltoid, the pus may burrow and appear at the anterior or posterior boundary of the axilla or in the axillary space. Pus formed in the joint tends to gravitate along the inter-tubercular groove. The axillary glands may be infected.

The primary lesion is either a caseating focus in one of the bones—most often in the upper end of the humerus—or it is of the nature of caries sicca. The greater part of the head may disappear, and the upper end of the shaft be drawn against the socket. In exceptional cases, portions of the glenoid or humerus are found separated as sequestra, or the disease involves parts outside the joint, such as the acromion or coracoid process. Hydrops with melon-seed bodies is rare. In young subjects, destruction of the tissues at the ossifying junction may result in considerable shortening of the arm.

The diagnosis is to be made from (1) arthritis deformans, in which the movements are less restricted, and are attended with grating and cracking; (2) paralysis involving the deltoid and scapular muscles—by the absence of pain, and the flail-like character of the movements; (3) disease in the sub-deltoid bursa—by the absence of rigidity and other evidence of implication of the articular surfaces; and (4) sarcoma of the upper end of the humerus—by the history of the case, the use of the X-rays or an exploratory incision. Injuries in the region of the upper epiphysis resulting in loss of movement, may, in the absence of a reliable history, be mistaken for tuberculous disease.