Gas Gangrene Following Posterior Tibial Tendon Transfer of a 34-Year-Old Patient - a Case Report.

Gas gangrene is a rare and potentially fatal surgical complication, most often associated with contaminated traumatic wounds or more rarely following cases of abdominal surgery. The following article describes a case of gas gangrene in the right lower limb of a 34-year-old patient following an elective posterior tibial tendon transfer. The surgery was performed in bloodless fashion, utilizing a surgical tourniquet. Fifteen months prior to the procedure, the patient was attacked by a wild boar, resulting in a tear of the upper calf with complete transection of the right common fibular nerve. The patient underwent a total of three acute surgical procedures, of which the third resulted in below knee amputation. The patient then underwent a final corrective procedure and was fitted with a suitable leg prosthesis. In the discussion, three possible pathophysiological mechanisms of gas gangrene development are described - iatrogenic inoculation of bacteria during injection of local anesthetics for conduction anesthesia, iatrogenic inoculation of bacteria during the posterior tibial tendon transfer and activation of latent clostridial spores within the original wound caused by the wild boar. We consider the third mechanism most likely, as boar tusks contaminated with soil and debris are a more likely source of clostridial spores, than sterile surgical instruments. Furthermore, it is likely the surgical tourniquet played a key role in activating latent spores within the patient wound, as changes in tissue oxygen levels are a common cause of spore activation. Thus, we suggest caution in utilizing bloodless operating fields in elective cases with a history of open contaminated wounds, as the iatrogenic hypoxia can potentially activate sporulent bacteria within the patients wound.