In attempting to save the limb of a young subject, it is justifiable to run risks which would not be permissible in the case of an older person. To save an upper limb, also, risks may be run which would not be justifiable in the case of a lower limb, because, while a serviceable artificial leg can readily be procured, any portion of the natural hand or arm is infinitely more useful than the best substitute which the instrument-maker can contrive. The risk involved in attempting to save a limb should always be explained to the patient or his guardian, in order that he may share the responsibility in case of failure.
Whether or not the amputation should be performed at once, depends upon the general condition of the patient. If the injury is a severe one, and attended with a profound degree of shock, it is better to wait for twenty-four or forty-eight hours. Meanwhile the wound is purified, and the limb wrapped in a sterile dressing. Means are taken to counteract shock and to maintain the patient's strength, and evidence of infection or of hæmorrhage is carefully watched for. When the shock has passed off, the operation is then performed under more favourable auspices. Clinical experience has proved that by this means the mortality of primary amputations may be materially diminished, especially in injuries necessitating removal of an entire limb.
Having decided to amputate, it is important to avoid having bruised, torn, or separated tissues in the flaps, as these are liable to slough or to become the seat of infection. In this connection it should be borne in mind that the damage to soft tissues is always wider in extent than appears from external examination.
The attempt to save a limb may fail and amputation may be called for later because of spreading infective processes, osteomyelitis, or gangrene; to prevent exhaustion from prolonged suppuration and toxin absorption; or on account of secondary hæmorrhage.
#Gun-shot Injuries of Bone.#--Fractures resulting from the impact of bullet or fragments of shell are of necessity compound, and are usually infected from the outset by organisms carried in by the missile or by portions of clothing or other foreign material. Not infrequently the missile lodges in the bone.