title: One-stage or two-stage revision surgery for prosthetic hip joint infection--the INFORM trial: a study protocol for a randomised controlled trial.
abstract: BACKGROUND
  Periprosthetic joint infection (PJI) affects approximately 1% of patients following total hip replacement (THR) and often results in severe physical and emotional suffering. Current surgical treatment options are debridement, antibiotics and implant retention; revision THR; excision of the joint and amputation. Revision surgery can be done as either a one-stage or two-stage operation. Both types of surgery are well-established practice in the NHS and result in similar rates of re-infection, but little is known about the impact of these treatments from the patient's perspective. The main aim of this randomised controlled trial is to determine whether there is a difference in patient-reported outcome measures 18 months after randomisation for one-stage or two-stage revision surgery.
  
  
  METHODS
  INFORM (INFection ORthopaedic Management) is an open, two-arm, multi-centre, randomised, superiority trial. We aim to randomise 148 patients with eligible PJI of the hip from approximately seven secondary care NHS orthopaedic units from across England and Wales. Patients will be randomised via a web-based system to receive either a one-stage revision or a two-stage revision THR. Blinding is not possible due to the nature of the intervention. All patients will be followed up for 18 months. The primary outcome is the WOMAC Index, which assesses hip pain, function and stiffness, collected by questionnaire at 18 months. Secondary outcomes include the following: cost-effectiveness, complications, re-infection rates, objective hip function assessment and quality of life. A nested qualitative study will explore patients' and surgeons' experiences, including their views about trial participation and randomisation.
  
  
  CONCLUSIONS
  INFORM is the first ever randomised trial to compare two widely accepted surgical interventions for the treatment of PJI: one-stage and two-stage revision THR. The results of the trial will benefit patients in the future as the main focus is on patient-reported outcomes: pain, function and wellbeing in the long term. Patients state that these outcomes are more important than those that are clinically derived (such as re-infection) and have been commonly used in previous non-randomised studies. Results from the INFORM trial will also benefit clinicians and NHS managers by enabling the comparison of these key interventions in terms of patients' complication rates, health and social resource use and their overall cost-effectiveness.
  
  
  BACKGROUND
  Current controlled trials ISRCTN10956306 (registered on 29 January 2015); UKCRN ID 18159.
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. simon.strange@bristol.ac.co.uk.|North Bristol NHS Trust, Brunel Building, Southmead Hospital, Westbury-on-Trym, Bristol, BS10 5NB, ᅟ. simon.strange@bristol.ac.co.uk.
authors.forename: Simon
authors.initials: S
authors.lastname: Strange
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. Michael.Whitehouse@bristol.ac.uk.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Whitehouse
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. Andrew.Beswick@bristol.ac.uk.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Beswick
authors.affiliation: Wrightington Hospital, Wigan and Leigh NHS Foundation Trust, Hall Lane, Appley Bridge, Wrightington, Lancashire, WN6 9EP, UK. tim@timboard.co.uk.
authors.forename: Tim
authors.initials: T
authors.lastname: Board
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. Amanda.Burston@bristol.ac.uk.
authors.forename: Amanda
authors.initials: A
authors.lastname: Burston
authors.affiliation: The Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation, Oswestry, Shropshire, SY10 7AG, UK. ben.burston@rjah.nhs.uk.
authors.forename: Ben
authors.initials: B
authors.lastname: Burston
authors.affiliation: School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS, UK. fcarroll@rcog.org.uk.
authors.forename: Fran E
authors.initials: FE
authors.lastname: Carroll
authors.affiliation: University of Exeter, St Luke's Campus, Heavitree Road, Exeter, EX1 2LU, UK. p.dieppe@exeter.ac.uk.
authors.forename: Paul
authors.initials: P
authors.lastname: Dieppe
authors.affiliation: School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS, UK. Kirsty.Garfield@bristol.ac.uk.
authors.forename: Kirsty
authors.initials: K
authors.lastname: Garfield
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. R.Gooberman-Hill@bristol.ac.uk.
authors.forename: Rachael
authors.initials: R
authors.lastname: Gooberman-Hill
authors.affiliation: Cardiff and Vale University Health Board, University Hospital Llandough, Penlan Road, Llandough, CF64 2XX, UK. sajones@doctors.org.uk.
authors.forename: Stephen
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authors.lastname: Jones
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. setor.kunutsor@bristol.ac.uk.
authors.forename: Setor
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authors.affiliation: School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS, UK. Athene.Lane@bristol.ac.uk.|Bristol Randomised Trials Collaboration, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS, UK. Athene.Lane@bristol.ac.uk.
authors.forename: Athene
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authors.lastname: Lane
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. Erik.Lenguerrand@bristol.ac.uk.
authors.forename: Erik
authors.initials: E
authors.lastname: Lenguerrand
authors.affiliation: North Bristol NHS Trust, Brunel Building, Southmead Hospital, Westbury-on-Trym, Bristol, BS10 5NB, ᅟ. Alasdair.Macgowan@nbt.nhs.uk.
authors.forename: Alasdair
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authors.lastname: MacGowan
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. a.j.moore@bristol.ac.uk.
authors.forename: Andrew
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authors.lastname: Moore
authors.affiliation: School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS, UK. S.M.Noble@bristol.ac.uk.
authors.forename: Sian
authors.initials: S
authors.lastname: Noble
authors.affiliation: School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS, UK. Joanne.Simon@bristol.ac.uk.|Bristol Randomised Trials Collaboration, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS, UK. Joanne.Simon@bristol.ac.uk.
authors.forename: Joanne
authors.initials: J
authors.lastname: Simon
authors.affiliation: Sheffield Teaching Hospitals NHS Foundation Trust, Northern General Hospital, Herries Road, Sheffield, S5 7AU, UK. Ian.Stockley@sth.nhs.uk.
authors.forename: Ian
authors.initials: I
authors.lastname: Stockley
authors.affiliation: Oxford University Hospitals NHS Foundation Trust, Nuffield Orthopaedic Centre, Windmill Road, Headington, Oxford, OX3 7HE, UK. ataylor@doctors.org.uk.
authors.forename: Adrian H
authors.initials: AH
authors.lastname: Taylor
authors.affiliation: Royal Devon and Exeter NHS Foundation Trust, Barrack Rd, Exeter, Devon, EX2 5DW, UK. andrewtoms@nhs.net.
authors.forename: Andrew
authors.initials: A
authors.lastname: Toms
authors.affiliation: North Bristol NHS Trust, Brunel Building, Southmead Hospital, Westbury-on-Trym, Bristol, BS10 5NB, ᅟ. Jason.Webb@nbt.nhs.uk.
authors.forename: Jason
authors.initials: J
authors.lastname: Webb
authors.affiliation: The Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation, Oswestry, Shropshire, SY10 7AG, UK. jp.whittaker@rjah.nhs.uk.
authors.forename: John-Paul
authors.initials: JP
authors.lastname: Whittaker
authors.affiliation: Royal Devon and Exeter NHS Foundation Trust, Barrack Rd, Exeter, Devon, EX2 5DW, UK. matthewwilson@nhs.net.
authors.forename: Matthew
authors.initials: M
authors.lastname: Wilson
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. V.Wylde@bristol.ac.uk.
authors.forename: Vikki
authors.initials: V
authors.lastname: Wylde
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Level 1 Learning and Research, Southmead Hospital, Bristol, BS10 5NB, UK. Ashley.Blom@bristol.ac.uk.
authors.forename: Ashley W
authors.initials: AW
authors.lastname: Blom
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D002985:Clinical Protocols; D003362:Cost-Benefit Analysis; D006621:Hip Joint / Q000601:surgery*; D006801:Humans; D007239:Infections / Q000601:surgery; D007592:Joint Diseases / Q000601:surgery*; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000601:surgery*; D036301:Qualitative Research; D011788:Quality of Life