RT Book, Section A1 Shah, Ashish A1 Sobolewski, Brad A1 Mittiga, Matthew R. A2 Knoop, Kevin J. A2 Stack, Lawrence B. A2 Storrow, Alan B. A2 Thurman, R. Jason SR Print(0) ID 1181044617 T1 Hair Tourniquet T2 The Atlas of Emergency Medicine, 5e YR 2021 FD 2021 PB McGraw-Hill PP New York, NY SN 9781260134940 LK accessmedicine.mhmedical.com/content.aspx?aid=1181044617 RD 2024/03/29 AB A single strand of hair or thread may encircle a finger, toe, or the penis, leading to circumferential strangulation of the appendage. Children in their 1st year of life are particularly at risk from inadvertent encirclement by a parent’s hair or loose thread especially within confining clothing. The affected digit appears edematous, erythematous, and painful. If not corrected, vascular compromise or infection can ensue. The differential diagnosis includes insect bites, trauma, cellulitis of the digit, osteomyelitis, or ainhum (dactylosis spontanea), a painful constriction in the base of the 5th toe of unknown etiology followed by spontaneous autoamputation months to years later.