Controlled nail trephination for subungual hematoma.

An injury to a finger or toe can result in a collection of blood under the nail plate that if unrelieved can cause extreme discomfort due to pressure. In this case, a 47-year-old man developed a subungual hematoma of the right thumb due to a crush injury. Controlled nail trephination was performed using a uniquely designed drill that penetrated the nail plate without breaching the nail bed. The subungual hematoma was successfully drained, and there was a substantial relief in pain over the subsequent 8 hours. This technique appears to be a quick and convenient method of evacuating subungual hematomas with minimal discomfort and minimal risk.