Surgery, with Special Reference to Podiatry Part 22

The limb is wrapped with strips of sheet-wadding from the toes to the middle of the thigh, and a circular plaster of Paris cast is applied extending over the same area. Before the cast is dry, it is cut open along the median line, in front, to allow for any swelling. The cast is best applied while the patient is under the influence of an anesthetic, so as to permit reduction of the fragments by traction upon the foot. In from ten days to two weeks the cast should be removed and a fresh one applied. The second cast does not require to be cut open, and can be left on the limb until the end of the fourth week. It is then removed and if union be complete, no further cast need be worn. Ma.s.sage of the limb and pa.s.sive and active motion are now begun.

+Fractures of the Tarsal Bones.+ Fractures of these bones have been found far more frequently than was thought before the use of the X-ray. Many cases of tarsal fracture have been treated for sprains of the ankle. It is only when the recovery is slow or the injury is followed by a traumatic flat foot that the surgeon begins to suspect that a more serious condition was present at the time of the original injury.

The astragalus and os calcis are the tarsal bones that are usually affected. Fractures of the os calcis, in the majority of cases, are due to compression. The patient falls from a height to the ground, on a hard substance. The os calcis is crushed between the astragalus and the ground.

There are three general types of fracture of the os calcis:

1. That in which the fracture has been confined largely to that portion lying behind a vertical plane through the middle of the body of the astragalus. There are three varieties of this heel fragment type: (_a_) cases with one large heel fragment; (_b_) cases of small heel fragments (in this variety, also called avulsion fracture, the sudden contraction of the calf muscles pulls the fragment off; at times the tendo Achillis itself is torn off from the attachment to the os calcis at the same time); (_c_) cases showing only fissures in the bone.

2. Comminution of the anterior half of the os calcis.

3. All the cases of extensive comminution of the bones; the bone is literally shattered.

+Fractures of the Astragalus.+ These can be divided into: (_a_) those of the neck; (_b_) those of the body. The former are the most common fractures of the astragalus. They may follow sudden dorsal flexion, or forced supination, or p.r.o.nation of the foot. They may be due to a fall from a height or from direct violence. Fractures of the body of the astragalus are usually the result of a crushing force which ordinarily have a like effect on the body of the os calcis, and are often a.s.sociated with fractures of the latter bone. The variety of fractures is considerable, varying from two large fragments, to complete comminution of the bone.

A fact of considerable importance in the interpretation of skiagraphs of fractures of the astragalus, is a knowledge of the presence in many normal individuals of a little bone known as the _os trigonum_. It may occur detached from the astragalus or may be attached to it as a process, on its posterior aspect, and on account of the swelling and pain around the ankle, a diagnosis can seldom be made without the routine use of the X-ray in every injury in this region.

The swelling, with obliteration of the depressions normally present around the ankle, does not differ from that characteristic of a sprain of the ankle or of a Pott's fracture. If there is extensive comminution of the os calcis or astragalus, the malleoli may be a little lower than normal.

The X-ray must always remain our most reliable means of diagnosis at the time of the injury. At a later period the chief symptoms are a painful flat foot, ankylosis of the ankle joint, pain and difficulty in p.r.o.nating and supinating the foot.

The prognosis of fractures of the tarsal bones is not favorable, even though the lesion has been recognized at the time of injury. Even in the most favorable cases there is some limitation of lateral motion.

The outlook is better in those cases of fracture of the os calcis in which there is a large heel fragment, than if the fracture is comminuted. The most frequent sequel is stiffness of the ankle-joint and traumatic pes valgus. Infection is frequent in compound fractures.

+Treatment.+ This does not differ from that of a Pott's fracture until the greater part of the swelling has disappeared. The skin of the foot and lower portion of the leg should be thoroughly cleansed and covered with gauze. This is necessary on account of the possibility of necrosis of the skin of the heel, and the danger of infection of the bruised soft tissues around the heel.

The foot should be placed in a well-padded box or in a posterior splint of the Volkman type. Ice bags should be applied over the sides of the heel.

After from eight to ten days, a circular plaster cast can be applied, extending from the toes to the knee. An anesthetic should be given during the application of the cast, the foot being held flexed at right angles and sheet wadding freely used around the ankle. The cast should be worn for seven weeks. At the end of this time the patient is gradually permitted to step upon the injured foot. Pa.s.sive and active motion are also now employed.

Fractures of the neck of the astragalus, with rotation of the posterior fragment, are usually followed by great limitation of the movements of the ankle joint. This condition might be greatly improved by an open operation.

+Fractures of the Metatarsal Bones.+ These are usually due to direct violence, as occurs when a heavy weight falls upon the dorsum of the foot. Another example of direct violence is a fracture following a crushing injury, as in being run over.

In indirect violence, such as follows dancing, jumping, or sudden twists of the foot, the fifth metatarsal bone is the one most often involved. There is but little tendency to displacement except when several bones are broken at the same time, and then it is toward the dorsum of the foot.

The diagnosis in fractures produced by direct violence is made from the following: presence of severe localized pain; swelling; and, not infrequently, crepitus and abnormal mobility. In those fractures due to indirect violence (second, third and fifth metatarsals), there is pain when the patient endeavors to put pressure upon the toes or tries to invert the foot. The usual signs of fracture are absent. A skiagraph should be made in every case.

Fracture of the metatarsal bones is liable to be followed by traumatic flat foot, on account of the sinking of the arch, or painful large calluses forming on the sole of the foot may interfere with walking.

+Treatment.+ The treatment in such fractures is by immobilization in a posterior metal or plaster splint, for four weeks. If there is continual pain upon walking after the injury, a steel insole will often give relief. The treatment of compound fractures of the metatarsal bones does not differ from that of other bones.

+Dislocations.+ A dislocation is a displacement from each other of the articular ends of the bones which enter into the formation of a joint.

A diagnosis can usually be made from certain objective and subjective symptoms, taken in conjunction with an accurate history of the manner in which the accident occurred.

Examination should be made in a systematic manner in every case, us follows:

(1) _Inspection._ The limb should be first inspected to note the position, the alterations of contour, or of the axis of the limb, or the projection or absence of certain bony prominences. The position is often so characteristic that a diagnosis can be made by inspection alone.

(2) _Palpation._ By this one can learn the relation of the displaced articular ends to each other, unless the swelling is too great, or the patient is very stout. This method also enables one to ascertain the absence of normal prominences or the presence of abnormal ones.

The end of the displaced bone may be felt in an abnormal position.

(3) _Measurement._ The limb may only appear to be or is actually shortened. In the latter event the normal measurements between bony prominences will be altered.

(4) _A skiagraph_ should be made in all doubtful cases to confirm the diagnosis of dislocation, and also to ascertain whether there is an accompanying fracture.

When the patient is stout, or when considerable swelling exists the use of the X-ray is of especial value.

The att.i.tude of the limb is often so characteristic that simple inspection will enable one to make a diagnosis by this means alone. In stout persons, a change in the axis of the limb or a change in position is apt to be overlooked. The relation of the articular surfaces can be determined by palpation, unless the swelling is too great. Measurement of the limb will usually show a shortening, depending upon the position in which the limb is held. The movements of a dislocated joint are usually limited. If any movement of the end of one of the bones is felt, it is always at an abnormal point. Pain is referred to the dislocated joint and the patient is unable to use the limb.

+Treatment.+ As a rule, a dislocation should be reduced as soon as the diagnosis is made, and, if necessary, an anesthetic should be administered.

When reduction has been accomplished, the bone often goes back with a snap, the contour of the limb is restored, and the movements of the joint are free again.

If it is impossible to reduce a recent dislocation, the following obstacles must be considered: (_a_) interposed portions of the capsule; (_b_) interposed muscles or tendons or sesamoid bones; (_c_) torn off fragments of bone; (_d_) a fracture of the shaft close to its articular end, which would prevent its being used as a lever for reduction.

The after-treatment of a dislocation is usually quite simple. A bandage or splint should be applied, which will keep the joint immobilized for a period of two weeks, after which pa.s.sive motion and ma.s.sage can be begun for fifteen minutes twice daily, the splint or bandage then to be reapplied for another two weeks.

+DISLOCATIONS AT THE ANKLE JOINT+

+Backward Dislocations+ occur more frequently than those in a forward direction.

The injury usually is the result of a fall backward while the foot is flexed. This causes an extreme plantar flexion of the foot. The astragalus, and with it the foot, is displaced backward. The lateral ligaments are usually extensively torn. In the majority of cases there is an accompanying fracture of either one or both malleoli or of the shaft of the fibula.

+Diagnosis.+ The front portion of the foot is shortened while the heel is more prominent than normal. The lower end of the tibia protrudes over the dorsum of the foot and the sharp edge of its articular surface can be distinctly felt. The extensor tendons and the tendo Achillis are tense and prominent. It may be distinguished from a supramalleolar fracture by the fact that the malleoli in the latter have moved backward with the foot, while in a dislocation backward they are prominent at some distance in front of the heel.

+Treatment.+ Reduction is usually effected by forced plantar flexion, the foot being pulled forward and the lower end of the tibia being pushed backward. These steps are then followed by dorsal flexion of the foot.

After reduction, the leg should be immobilized for three weeks in a molded posterior splint. Light pa.s.sive motion can be begun during the fourth week. In old unreduced cases an arthrotomy is indicated.

+Forward Dislocations.+ These are much rarer than the backward form.

They are usually due to a forced dorsal flexion of the foot. This form is less often accompanied by a fracture of the malleoli than is the case in the backward dislocation. The fibula is seldom broken, the usual seat of the fracture being in the tip of the internal malleolus or in the articular surface of the tibia.

+Diagnosis.+ The whole foot appears to be lengthened. The prominence due to the heel has disappeared; the upper articular surface of the astragalus can be felt, the tibia and the malleoli being nearer to the heel.

The condition can be differentiated from a fracture of both bones of the leg above the malleoli by the fact that in a forward dislocation the malleoli are further back than normal, while in a supramalleolar fracture they have moved forward with the foot.

+Treatment.+ Reduction is readily effected by marked dorsal flexion of the foot, pressure being made in a forward direction upon the lower end of the tibia, and the foot pushed backward. Plantar flexion now completes the reduction. The after treatment is the same as in the backward form.

+Lateral Dislocations.+ The other forms of dislocations seen in the ankle are those in a lateral direction, either inward or outward. The diagnosis is usually easy. The upper convex surface of the astragalus is directed toward the external malleolus and can be felt there. The inner border of the foot is raised; the outer rests upon the bed.

This form of dislocation is very frequently a compound one, or it is accompanied by fractures of the bones of the leg or of the astragalus; but it may occur without these injuries.

+Treatment.+ The treatment of these lateral dislocations differs but little from that of fractures of the lower end of the tibia and fibula. Reduction is effected by adduction or abduction of the foot.

The chief danger is from infection on account of the extensive injury of the skin and soft parts. If reduction is impossible, perform an arthrotomy.

+Subastragaloid Dislocation.+ Two forms of dislocation can occur in the joint between the astragalus and the two tarsal bones (os calcis and scaphoid) with which it articulates. In the true subastragaloid form, the astragalus continues to articulate with the tibia and fibula, but it is displaced from its articulation with the os calcis and scaphoid.