“Hair-thread tourniquet syndrome” refers to conditions in which an appendage (e.g., finger, toe, or penis) is circumferentially constricted by a hair or thread, leading to impairment of lymphatic and eventually venous return (1,2). Cases involving entrapment of other body parts, such as the female genitalia (clitoris and labia), though unusual, have also been reported (3). Hair tourniquets most frequently occur in the first few months of life, although they occasionally occur in toddlers. Normal perfusion is restored by unraveling the hair or cutting the constricting band and thereby eliminating the vascular compression. Principles that should be adhered to when releasing the constricting band include protecting entrapped soft tissue from harm and avoiding injury to the neurovascular and tendon structures of the appendage. The removal procedure in most cases can be performed in the ambulatory office or the emergency department. This procedure is usually performed by an emergency physician, general pediatric practitioner, or family physician, but if significant edema has occurred, with ensuing distortion of tissues, surgical consultation may be necessary.

Anatomic structures involved in a digital hair tourniquet include the layers of the skin as well as the nerves, blood vessels, and lymphatics (Fig. 112.1). The neurovascular bundles of the fingers and toes are located on the dorsal and palmar or plantar aspects of both the radial and ulnar margins. The major neurovascular structures of the penis and clitoris are located on the dorsal surface at the 12 o’clock position. Deeper structures of the penis that may become involved include the dorsally located corpora cavernosum and also the corpus spongiosum, which is located on the ventral surface and surrounds the urethra (4).

Hair tourniquets have been associated with postpartum hair loss (telogen effluvium), mothers with long hair (particularly blonde hair in the case of a Caucasian child), use of mittens or booties in infants, and hair shed in the bathtub (2,5,6,7). Child abuse must be considered, especially in cases involving the penis, as several reports have been made of tourniquets being placed intentionally (2,8). It is postulated that often the offending hair is wet when it first becomes wrapped around the appendage. The hair contracts as it dries, leading to the initial constriction (1,5,9,10).

Constriction of venous and lymphatic vessels, with inhibition of venous return, by a hair tourniquet leads to edema and progressive swelling. This compounds the compression of the vessels and compromises distal perfusion in a vicious cycle. If the constricting agent remains in place long enough, it can cut through the skin layers. Epithelialization may then occur, obscuring the hair beneath an overlying skin bridge. Injury may be caused by ischemia and by direct damage to structures through the cutting action of the tourniquet. Necrosis and gangrene of digits (5,6,8) and erosion through the urethra, with resulting fistula formation, have been reported (11,12,13).

The child with a constricting band of hair or thread may present in several ways. Most frequently, the child has an erythematous, swollen, painful appendage. When inspected carefully, the appendage exhibits a sharp, circumferential demarcation beyond which it is affected. At the point of demarcation, an extra crease or indentation is noted. Because of the difficulty in localizing a source of pain in the infant, it is
important not to overlook this as a possible diagnosis when evaluating the presentation of irritability and crying (3).