NINJA RCT – Should We Replace the Nail After Nail Bed Repair? 

November 24, 2023

Written by Christian Gerhart

Spoon Feed
In this multicenter, randomized controlled trial comparing suturing the fingernail back onto the nail bed versus simply covering the nail bed with a non-adherent dressing after repair of a nail bed injury, there was no statistically significant difference in infection rate or cosmetic outcome. 

NINJA: An excellent study with an even better name
The Nail bed INJury Analysis (NINJA) study was a multicenter randomized controlled trial which included 451 children less than 16 years old (average age was 5.9) who sustained a nail bed injury within the previous 48 hours, which was believed to require a surgical repair. Patient were randomized to debridement and suturing of the nail bed, and the fingernail was sutured over the repair with a figure-of eight Vicryl Rapide suture (usually 6-0 or 7-0). If the fingernail could not be used, a substitute, usually foil, was utilized. The other group simply underwent debridement and suturing of the nail bed without the fingernail being sutured back on and had the nail bed covered with a low-adherent dressing. The authors had co-primary outcomes of surgical-site infection (SSI) rates at 7-10 days and cosmetic appearance of the nail as measured by the Oxford Fingernail Appearance Score (OFNAS).   

The rate of surgical site infection at 7 days was not statistically significant between the two groups, though there was a slightly higher rate infection with replacement of the fingernail (OR 2.49, 95% CI 0.58 to 10.61).  There was also no statistically significant difference in the cosmetic outcomes between the two groups or any of the secondary outcomes (pain at dressing change, late incidence of SSI, parent/child satisfaction with nail appearance or health related quality of life scores). Replacing the nail was associated with an approximately £75 (that’s about $93) higher cost per patient due mainly to longer operating room times.  Interestingly, the injuries were all managed in the operating room but would be treated at the bedside by an EM provider in the United States, which may decrease the paper’s generalizability.

How will this change my practice? 
The study is well done (has to be with a name like NINJA). The option to simply remove the nail and repair the laceration without having to worry about a complex replacement of the nail in a busy ED would be a time and energy saver. Although this is just one study, I think it would be reasonable to consider this strategy, assuming the hand consultants who will follow the patient in clinic are accepting of the practice.

Source
Effectiveness of nail bed repair in children with or without replacing the fingernail: NINJA multicentre randomized clinical trial. Br J Surg. 2023 Mar 30;110(4):432-438. doi: 10.1093/bjs/znad031.