Nail bed INJury Analysis (NINJA) Definitive RCT

  • Connector.

    Update 30/10/2017

    The NINJA-Pilot RCT has been published in the BJS. Click to download:

  • Connector.

    Update 19/07/2017

    The NINJA-Pilot RCT has been accepted for publication in the British Journal of Surgery.

    The NINJA team is now recruiting sites for the main RCT. Please sign up below if you are interested.

  • Connector.

    Update 07/04/2017

    The NINJA RCT has been awarded funding by the NIHR RfPB (£350K). We are now recruiting units for the definitive trial. If you are interested, please sign up below.

  • Connector.

    Update 01/04/2016

    The team have submitted a first stage application to the NIHR RfPB panel for funding for a full trial.

  • Connector.

    Update 01/01/2016

    The NINJA-Pilot data is being analysed. The original audit data and clinician and patient surveys have been published as has the NINJA-P protocol. Details in the 'outputs' box.

Should the nail plate be replaced or discarded after nail bed repair in children?

The NINJA Pilot Study (funded by the British Society for Surgery of the Hand, BSSH) was a pragmatic multicentre study to assess whether the nail should be replaced or discarded after nail bed repair in children. The pilot was completed in 2015 and will inform the design and conduct of the forthcoming definitive NINJA RCT. The Surgical Intervention Trials Unit (SITU) at the University of Oxford, will co-ordinate the trial. This is the first plastic surgery trial of its kind and will form part of a developing research portfolio for the plastic surgery community.

Register to become a NINJA centre

The definitive NINJA trial will recruit from 20-30 units. The study will be on the NIHR Portfolio meaning the hospital will receive funding for each patient recruited. Please sign up below if you would like your centre to be considered. Each unit will undergo assessment for suitability.


Nail bed injuries are common and account for the majority of paediatric hand trauma cases treated by hand surgery units. The typical patient is a toddler who has caught their finger in a closing door. A single tertiary referral hand surgery unit will on average treat two to three patients with nail bed injuries per day.

Despite their frequency, controversy remains around the best treatment of nail bed injuries. Without proper treatment, injury to the nail complex has the potential to cause considerable dysfunction and/or deformity. The long-accepted surgery to repair the nail bed involves removing the fingernail (which is often broken or partially detached already) and carefully repairing the nail bed underneath using tiny dissolving stitches. This is important to help the new nail to grow out smoothly and look as normal as possible in the future. After repairing the nail bed, the surgeon can do one of two things:

1. Replace the old nail before applying dressings

2. Discard the nail and apply dressings straight onto the nail bed.

In both techniques, a new fingernail grows out from the base of the nail bed over a few months. The old nail cannot grow again after it has been removed and it is eventually pushed off by a new nail growing underneath it. Both of these techniques are routinely done by surgeons in the NHS, but we don’t know which one is best.

The rationale for replacing the nail is that it both protects the nail bed repair and acts as a ‘splint’ by holding open the nail fold and preventing scarring between the nail fold and the nail bed (synechiae). However, there is no evidence that replacing the nail has better results than not replacing it and there is a suggestion that it may be associated with a small risk of infection. Therefore the aim of a large NINJA study will be to find out if there is any difference between the two techniques.


Assess and monitor recruitment of patients to a study of this nature
Identify any conflict or areas of concern with conducting research with this patient population and with the Plastic Surgery network
Evaluate the recruitment process
Test assessment tools to be used
Monitor patient compliance with follow up procedures
Gather information to develop the larger study and to calculate how many patients will be required for this
Randomisation will occur in the anaesthetic room via an internet portal. Follow up is at 2 weeks, 30 days and 4 months post randomisation.

  • Protocol development
  • Audit published
  • NRES approval
  • Pilot RCT Protocol published
  • Pilot RCT Data collection
  • Manuscript submission
  • Publication
  • Definitive RCT funding
  • NINJA RCT site set up
  • NINJA RCT patient recruitment
  • NINJA RCT data analysis
  • NINJA RCT publication
Abhilash Jain
Co-Chief Investigator
NDORMS, Oxford

Aina Greig
Co-Chief Investigator and PI at Lead Site
Guy’s and St Thomas’ NHS Foundation Trust

Dominic Furniss
Principal Investigator
Oxford University Hospitals NHS Trust

Claire Zweifel
Principal Investigator
Mid Essex Hospital Services NHS Trust

Richard Pinder
Principal Investigator
Hull and East Yorkshire Hospitals NHS Trust

David Beard
SITU, Oxford

Jonathan Cook
Associate Professor
Centre for Statistics in Medicine, Oxford

Adam Sierakowski
Mid Essex Hospital Services NHS Trust
‘Trainee’ Lead, NINJA Study Group

Matthew D. Gardiner
Trainee Lead, RSTN

Cushla Cooper
Research Portfolio Manager
SITU, Oxford

Nicola Farrar
Clinical Trials Administrator
SITU, Oxford

Reconstructive Surgery Trials Network Nail bed INJury Analysis (NINJA) Collaborative

This group conducted the audit, clinician and patient surveys.

Frank Acquaah, Sadia Afzal, Shirwa Sheik Ali, David Beard, Kamal Bisarya, David Bruce, Jonathan Cook, Cushla Cooper, Nicola Farrar, Dominic Furniss, Jenifa Jeyakumar, Max Horwitz, Hawys Lloyd-Hughes, Natalie Pease, Gordon McArthur, Adrian Murphy, Julia Ruston, Hassan Soueid, Makarand Tare, Ricardo Tejero, Evgenia Theodorakopoulou and Claire Zweifel.

NINJA Pilot Collaborative

Guy’s and St Thomas’ NHS Foundation Trust: Riaz Agha, Waleed Albadry, Yeliz Cemal, Priyanka Chadha, Declan Collins, Henrietta Creasy, Asmat Din, Magda Ferreira, Federica Maggiulli, Antonios Mitsakos, Alexandra Molina, Tom Pampiglione, Matthew Pywell, Karen Richards, Yasmin Tavsanoglu, Ricardo Tejero, Sarita Vamadeva, Ruby Wang, Matthew Wordsworth. Hull Royal Infirmary: Will Holmes, James Haeney, Neil Brierley, Elaine Pardoe, Charde Naylor. Mid Essex Hospital Services NHS Trust: Tereze Laing, Iraklis Delikonstantinou, Natalie Whybro, Helen Gerrish. Oxford University Hospitals NHS Trust: Emma Gammin.



Gardiner MD, Jain A, Sierakowski A, Grieg A on behalf of the RSTN NINJA Collaborative*. Results of a national survey of nail bed repair practice. BSSH Autumn Scientific Meeting 2014, London

Greig A on behalf of the NINJA Pilot Trial Group*. Nail bed INJury Analysis (NINJA). BAPRAS Winter Scientific Meeting 2015, Birmingham.


Sierakowski A, Gardiner MD, Jain A, Grieg A and RSTN NINJA Collaborative*. Surgical treatment of paediatric nail bed injuries in the United Kingdom: Surgeon and patient priorities for future research. JPRAS 2015. In press.

Jain A, Sierakowski A, Gardiner MD, Beard D, Cook J, Cooper C, Greig A. Nail bed INJury Assessment Pilot (NINJA-P) study: should the nail plate be replaced or discarded after nail bed repair in children? study protocol for a pilot randomised trial. Pilot and Feasibility Studies 2015. 1-29.

*See collaborators section

No downloads available
We are now recruiting units for the definitive trial.