2nd. Surgical Cleaning. - After a little time, in wounds accompanied by injuries to bone, the amelioration resulting from the application of the antiseptic is arrested. The number of microbes found on the surface of the wound remains stationary. But, on the other hand, suppuration has diminished or dried up, the tissues are no longer swollen, and the patient is ready for surgical intervention.

Then the wound is cleansed just as though it were a fresh one. Under anaesthesia, foreign bodies and necrotic tissues are removed.

In the case of suppurating fractures, the method of procedure is slightly different, according as intervention is practised before or after consolidation. This point was recently cleared up at Compiegne by the researches of MM. Guillot and Woimant.

(a) Before Consolidation. - It is an easy matter to explore the bony extremities. Incisions will not necessarily be made in already existing wounds. Whenever it is possible to do so without involving a fresh and extensive traumatism, it is best to choose the classical paths of surgical access, while avoiding those which, being in a sloping position, are not very favourable to irrigation. Between the bony extremities, or in their neighbourhood, will be fragments of necrosed bone and splinters. The former having been removed, the latter will be sacrificed only if they show signs of necrosis, or if they hinder the inspection of the seat of the fracture, and its irrigation. The bony extremities will be carefully examined, for the result of the operation is directly dependent upon their treatment. When they are filled by a medullary plug, it is necessary to make sure, by scraping the latter with the curette, that it is healthy, without fissures or enclosed sequestra, in which case it is certain that the underlying medullary cavity is practically sterile. In the contrary case it is necessary to remove the whole thickness of the plug, and to provide for drainage, by scraping a groove in the dense tissue for a depth of two-fifths of an inch. The same procedure will be followed in the case of bony extremities which are left opening into the seat of the fracture. This precaution of opening up a wide passage for the irrigation tubes in the dense tissue is of the greatest importance if we wish to avoid violent post-operative febrile reactions.

(b) After Consolidation. - The exposure of the bony extremities presents more difficulty. In the first place, the path of access is obstructed by fistulas which have to be resected, and the formation of callus. When the orifice of an osseous fistula is reached through the soft parts, the periosteum is detached from the callus by means of a sharp rugine, taking care not to denude it too far. The curette then enlarges the fistula, enabling the bone-forceps to come into play, and permitting of the resection of the periosteal callus and the fragments, which is necessary to the cleaning-up of the cavity of the seat of fracture, and the exploration of the medullary cavities. The treatment of the bony extremities thus exposed will be the same as before consolidation.

The capital point in the operative treatment of old fractures inclined to suppurate is to practise complete but economical operation. In short, the abrasion of the bony tissue must be compatible with the reunion of the soft parts after the few days necessary for sterilisation.

It <is obviously possible to treat old fractures in a single surgical operation by an extensive sub-periosteal resection, going considerably beyond the boundaries of the lesion in both directions. But this method of procedure is incompatible with secondary reunion; it must be regarded as a surgical technique which was excellent in times when one could not imagine the reunion of infected wounds.

In a case of suppurative arthritis, if necessary, resection of the bony extremities is practised. At this stage the surgical interventions found absolutely necessary may be carried out with much less danger than when the patient "came in." It must be borne in mind, however, that tissues which have already commenced to cicatrise during the stage of suppuration are impregnated with microbes and that reinfections are possible. Therefore operations involving the least possible amount of traumatism should be chosen.

Wounds of the soft parts, as a rule, become aseptic under the influence of the antiseptic without a new operation being necessary.

3rd. Chemical Sterilisation. - The surgical cleaning-up is followed by the introduction of instillation tubes precisely as though dealing with a fresh wound. It is necessary to keep the wound gaping so long as its deeper parts are not sterilised. This result is attained by placing in the wound short segments of tube of wide calibre, by the side of which are introduced the small tubes for instillation.

In the case of fractures operated on during the suppurative stage, MM. Guillot and Woimant have shown that certain precautions are necessary in order to limit post-operative reactions. Our aim should be to deprive the bacteria of the media of culture which are favourable to them: blood-clots and contused tissues. The blood-clots are avoided by a thorough haemostasis with the forceps, which is completed, as regards the osseous and medullary oozing, by a prolonged irrigation with warm serum. The rapid elimination of the contused tissues will be achieved, on the one hand, by an abundant irrigation performed at short intervals, every hour or even every half-hour, if an automatic apparatus is available.

D. Cicatricial Stage

The cicatrisation of a wound does not mark the end of infection. In fact, microbes remain included in the cicatricial tissue. Therefore secondary interference practised on a patient whose wounds have healed, during a period of suppuration more or less long, is subject to special rules. Every one knows that after stump-trimming, nerve-suture, osteotomy for defective union, suture for pseudarthrosis, etc., infections, sometimes most alarming, may arise. It is therefore prudent, in these secondary interventions, to refrain from suturing the wounds, and to place in the deepest parts one or two tubes carrying the antiseptic liquid. The sterilisation of operation wounds is thus rapidly obtained, and the accidents due to reinfection avoided. In bone-grafting, the extremities of the bone are prepared for the reception of the graft, and in the wound thus created instillation tubes are placed. After a few days, it is ascertained that the wound is actually aseptic, and then the grafting is completed and the soft parts closed.

In a word, during the cicatricial stage, surgical interference practised in two stages, which are separated by a period of disinfection, is the surest means of avoiding disaster.