Subcutaneous tissue emphysema of the hand secondary to noninfectious etiology: a report of two cases.

Subcutaneous emphysema of the hand can be benign and noninfectious in origin. Emphysema from gas-forming organisms is associated with systemic symptoms, whereas benign subcutaneous emphysema is not. High-pressure pneumatic tool injuries are a well-known cause of subcutaneous emphysema. Minor wounds in the web space skin may result in a transport of air across the defect, acting like a ball valve mechanism to trap and then force the air into the subcutaneous tissue, as illustrated by 1 of our patients. In the second patient, use of a high-vibration tool without apparent breach of skin was associated with extensive subcutaneous emphysema. The benign nature of the emphysema was revealed by a lack of local pain and inflammation in the presence of extensive crepitus and a lack of systemic symptoms. A noninfectious cause should always be considered. This may prevent unnecessary surgical intervention, which occurred in 1 of the 2 cases presented here.