The HAT trick allows for scalp laceration closure by using scalp hair and tissue adhesive glue. Contraindications to this technique for wound closure include hair strands less than 3 cm, because it is difficult to manually manipulate short hair.
Trick of the trade: Modified HAT trick
The modified version of the HAT trick (modHAT) uses Kelly clamps to allow for instrument-manipulation of the hair bundles. This is different from the traditional technique, where the provider twists hair strands manually. The Kelly clamps allow the provider to twist hair strands as short as 1 cm.
In a study with 67 patients, there were very few complications. One patient developed local alopecia in the area of the laceration. This likely was caused by excess tissue adhesive spilling into the wound itself.
Another noted complication was the tissue adhesive glue not peeling off of the hair after 2 weeks. In 7 of the 67 patients, they cut off the "hair-glue knot". This likely was because more than 1 drop of glue was applied to each twisted hair bundle. By applying only 1 drop per bundle, the patient can more easily tweeze the glue off with a comb. Bottom line: More is NOT always better.
Reference Karaduman S, et al. Modified hair apposition technique as the primary closure method for scalp lacerations. Amer J Emerg Med (2009) 27, 1050–5.