Scalp lacerations over hair-bearing areas have traditionally been closed with staples. An alternative technique is the Hair Apposition Technique, also known as the HAT trick. This technique provides a more cost-effective, faster, and less painful approach to scalp laceration repair. This is not a new thing. It’s been discussed in the literature since 2002, but it astounds me how many experienced practitioners have not adopted this simple and time-saving technique.
How does the HAT trick work? Imagine the scalp hairs as suture ties already embedded in the skin. After 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. No need to tie a knot. Secure the intertwined hair bundles by applying a few drops of a tissue adhesive. Not only can you often get away with doing this technique without injection of an analgesic, the patient no longer needs to return for staple removal in 7-10 days. The hair will unravel on its own after a week. So, you also save them a return visit.
What people don’t often realize is that hair apposition isn’t just for tiny scalp lacs. It’s an evidence based technique, and has been studied for safe use in lacerations as long as 10 cm. You can repeat as needed to close the length of the laceration.
It’s also important to recognize that hair apposition is not just for the rapunzels out there with long, glorious flowing locks. It works great in short haired people too. The only real modification you have to make is to get a pair of kelly clamps, lock up the hair on both ends, twist, and glue.
References for this technique:
- Hock MO, Ooi SB, Saw SM, et al. A randomized controlled trial comparing the hair apposition technique with tissue glue to standard suturing in scalp lacertions (HAT study). Ann Emerg Med. 2002;40(1):19–26.
- Ong ME, Coyle D, Lim SH, et al. Cost-effectiveness of hair apposition technique compared with standard suturing in scalp lacerations. Ann Emerg Med. 2005;46(3):237–242.