Fractures, in Surgery, are classified in several different ways. As regards the fractured bone itself, it may be merely broken across, either transversely or obliquely, the commonest injury; or broken into several pieces (comminuted fracture); or only cracked (fissured fracture, the most usual fracture of the skull); or partly broken, partly bent (greenstick fracture, occurring in the bones of the limbs in children); or one part of the bone may be forcibly driven into the other (impacted fracture). But the most important classification of fractures is concerned with their relation to the surrounding parts. In a simple fracture there is no wound of the skin communicating with the fracture; in a compound fracture there is such a wound; in a complicated fracture there is some other injury (e.g. a flesh-wound not communicating with the fracture, a dislocation, a rupture of a large blood-vessel). The distinction between simple and compound fractures is of special importance, as the latter are very much more serious than the former, chiefly on account of the risk of pyæmia or septicæmia, and their repair much more tedious; though the dangers attending them have much diminished since the introduction of the antiseptic method. See ANTISEPTIC SURGERY.
Fractures are most common in the long bones of the limbs, particularly the collar-bone, the radius just above the wrist, the thigh-bone, and the fibula. They are rather less frequent in children than in adults, and much less in women than in men.
Causes of Fractures.—The predisposing causes which render bones specially liable to fracture may be local—e.g. necrosis or tumour affecting a single bone, or general—e.g. cancerous cachexia, the diseases called mollities and fragilitas ossium, and old age, all which render the bones generally less able to bear a strain. There is one predisposing cause to fracture fortunately now but seldom seen—viz. scurvy. Not only did it make the bones brittle, but, as was seen in Lord Anson's expedition, which was manned chiefly by pensioners, old fractures again became disunited. The immediate cause may be either external violence or muscular action. The external violence producing a fracture may be either direct or indirect. In the former case the bone yields at the point where the force is applied, and there is always more or less bruising of the adjacent soft parts by the body which causes the fracture—e.g. when a limb is broken by a heavy wheel passing over it, or a stone falling upon it. In the latter case the bone gives way at some point between two opposing forces, and the adjacent tissues are not injured except by the broken ends of the bone—e.g. when a person falls upon his hand, and the radius or humerus gives way. The worst fractures are thus in general those produced by direct violence. Muscular action not unfrequently leads to the fracture of bones into which powerful muscles are inserted, particularly the kneecap, by simply tearing them asunder. The subject of the injury may then fall, and attribute the accident to the fall, whereas the reverse is the case. A medical man some years ago awoke with a fit of cramp, and almost immediately his left thigh-bone broke with a snap. It reunited in the usual time.
Symptoms of Fracture.—Fracture of a limb is attended by pain, swelling, and loss of power; but these do not suffice to distinguish it from other forms of injury. Deformity other than swelling (shortening, angling, or unnatural rotation of the injured limb), abnormal mobility at the seat of injury, and a rough grating sound and feeling (called crepitus) when the limb is so moved as to rub the broken surfaces together are the most satisfactory evidences of fracture. The patient, moreover, may have observed the sound of the break when the bone gave way. But in a case where fracture is suspected the investigation of it should be deferred till the patient has been placed where he is to be treated.
Repair of a Broken Bone.—The immediate result of a fracture is considerable extravasation of blood into the tissues around it, from the blood-vessels torn across by the injury. It is not quite certain whether some of this blood takes part in the healing process; most of it at all events is simply absorbed. But during the days following the fracture slight inflammation (q.v.) of the wounded tissues takes place, and inflammatory lymph (here called callus) is thrown out between and around the broken ends of the bone. Slow organisation of the callus takes place, and in from three to six weeks it is usually converted into bone, firmly cementing the fragments together. In man, when the fracture is set in good position, there is generally little more lymph effused than suffices to restore the natural outline of the bone; but in animals the break is generally ensheathed in a large mass of it, called provisional callus, which steadies the bone till the permanent callus between the ends of the bones has become ossified; then the provisional callus, being no longer necessary, is absorbed.
Treatment of Fracture.—When a fracture has taken place it is important that there should be as little disturbance as possible of the injured part till it is to be finally adjusted by the surgeon. Many simple fractures, especially of the lower limb, are made compound by ignorance or carelessness on the part of the injured person or of officious onlookers. The injury should therefore be attended to first on the spot where it has been received; the limb should be fixed by handkerchiefs or strips of cloth to anything at hand firm enough to keep it temporarily steady (a walking-stick, rifle, broom- handle, &c.), or, in the case of the lower limb, to the other leg. When this has been done the patient may more safely be removed to the place where he is to remain during treatment.
The object of the surgeon in setting a fractured limb is to place the fragments as nearly as possible in their natural relation, and to retain them firmly in this position during healing. The first end is attained by extending the broken limb and moulding it with the hands; the second is opposed by the action of the muscles of the part which, pricked by the broken ends of bone and stimulated into painful spasms, tend to restore the deformity. Their action must be counteracted by the adjustment of some form of splint or external rigid apparatus to the limb, differing in material, shape, and method of application according to the seat of the fracture. Splints are usually made of wood, pasteboard, or gutta-percha, and fixed on by straps or bandages; but in some simple fractures, especially of the lower limb, it has been found sufficient to encase the injured limb in a bandage impregnated with some material which will harden on drying and form a shell for it (starch, silicate of soda or 'water-glass,' plaster of Paris); in this way the patient's confinement to bed may be much shortened.
Treatment of fractures may lead to an unsatisfactory result in either of two contrary ways: when the vitality is low, or the treatment has not secured perfect rest of the broken bone, it may become united merely by fibrous tissue instead of bone, leaving a flail-like useless limb (ununited fracture, or false joint); or, when rest has been too long and continuous, the healing process may not merely reunite the bone, but fix the surrounding tendons and ligaments by fibrous adhesions, leaving more or less obstinate stiffness of the neighbouring joints. The former is in general more apt to occur in the shafts of the long bones, the latter close to their ends, and the treatment must be modified accordingly.
Fractures of the bones of the head and trunk are dangerous more on account of the risk of laceration of the important organs enclosed by them than because of the injury to the bones themselves; and in general any attempt to 'set' such fractures is apt to do more harm than good. Means must simply be taken to keep them as much at rest as possible.