Scalp lacerations over hair-bearing areas require wound closure, usually with staples. An alternative technique is the Hair Apposition Technique, also known as the HAT trick. [1, 2] This technique provides a more cost-effective, faster, and less painful approach to scalp laceration repair. Imagine the scalp hairs as suture ties already embedded in the skin.
What are the steps for the HAT trick?
- Perform wound irrigation and a meticulous examination.
- Twist together 3-7 strands of hair on one side of the wound.
- Do the same on the other side of the wound.
- Interlock these two hair bundles in a 360-degree revolution. Do not tie a knot.
- Secure the intertwined hair bundles by applying a few drops of a tissue adhesive.
- Repeat as needed to close the length of the laceration.
- The patient no longer needs to return for staple removal in 7-10 days. The hair will unravel on its own after a week.
Contraindications for using the HAT trick:
- Scalp lacerations more than 10 cm
- Grossly contaminated wounds
- Active bleeding from the laceration
- Significant wound tension
- Hair strands less than 3 cm in length
1. Ong ME, Coyle D, Lim SH, Stiell I. Cost-effectiveness of hair apposition technique compared with standard suturing in scalp lacerations. Ann Emerg Med. 2005 Sep;46(3):237-42.
2. Hock MO, Ooi SB, Saw SM, Lim SH. A randomized controlled trial comparing the hair apposition technique with tissue glue to standard suturing in scalp lacerations (HAT study). Ann Emerg Med. 2002 Jul;40(1):19-26.