1458 THE BONE & JOINT JOURNAL  HIP Outcomes following debridement, antibiotics and implant retention in the management of periprosthetic infections of the hip A REVIEW OF COHORT STUDIES S-T. J. Tsang, J. Ting, A. H. R.W. Simpson, P. Gaston From University of Edinburgh, Edinburgh, United Kingdom  S-T. J. Tsang, BSc(Hons) MBChB MSc MRCSEd, Clinical Research Fellow, Department of Trauma and Orthopaedics  J. Ting, MBChB MRCSEd, Foundation Doctor, Department of Trauma and Orthopaedics  P. Gaston, MBChB(Hons), FRCSEd, FRCS(Tr&Orth), Consultant Orthopaedic Surgeon, Department of Trauma and Orthopaedics University of Edinburgh, Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh EH16 4SA, UK.  A. H. R.W. Simpson, MA(Cantab), DM (Oxon), FRCS(England & Edinburgh), George Harrison Law Professor of Orthopaedic Surgery, Department of Orthopaedics University of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh, EH16 4SA, UK. Correspondence should be sent to Mr S-T.J. Tsang; email: Jerry.Tsang@ed.ac.uk ©2017 The British Editorial Society of Bone & Joint Surgery doi:10.1302/0301-620X.99B11. BJJ-2017-0088.R1 $2.00 Bone Joint J 2017;99-B:1458–66. Received 24 January 2017; Accepted after revision 05 July 2017 Aims The aims of the study were to review and analyse the reported series of debridement, antibiotics and implant retention (DAIR) in the management of infected total hip arthroplasties (THAs) to establish the overall success and the influencing factors. Patients and methods Using a standardised recognised study protocol, meta-analysis of observational studies in epidemiology guidelines, a comprehensive review and analysis of the literature was performed. The primary outcome measure was the success of treatment. The search strategy and inclusion criteria which involved an assessment of quality yielded 39 articles for analysis, which included 1296 patients. Results The proportion of success following DAIR in the management of an infected THA appeared to improve after 2004 with a pooled mean proportion of success of 72.2%. For all reported series, from 1977 onwards, there was improved success with early debridement (< 7 days; 75.7%) and exchange of modular components (77.5%). There was a statistically non- significant improvement if debridement was performed within four weeks of the initial procedure (73.0%). Conclusion The reported success following DAIR has improved since 2004. The only determinants of outcome which we found were the timing of debridement after the onset of symptoms of infection and the exchange of modular components. Cite this article: Bone Joint J 2017;99-B:1488–66. In the United Kingdom, more than 100 000 primary total hip arthroplasties (THAs) are performed annually. 1,2 The numbers, both in the NHS and private healthcare sector, have soared during the last decade and are expected to continue rising over the next 25 years. The most feared complication of THA is infection due to its resistance to treatment with antibiotics. 3 The choice of treatment for periprosthetic joint infections (PJIs) generally depends on a number of factors, including local factors involving the condition of the bone and soft tissue, the fixation and stability of the components, the chronic nature of the infection, the type of organism and the gen- eral condition of the patient. 3-5 In early infec- tion, within four 4 to twelve 3 weeks of surgery, debridement, antibiotics and implant reten- tion (DAIR) can be the initial treatment. 3,4 However, the proportion of patients which respond to DAIR ranges between 14% 6 and 100%. 7-9 This form of treatment of acute infections was first reported in 1974 by Müller 10 and then by Coventry 11 in 1975 with a rate of success of 80% and 20%, respec- tively. Burton and Schurman 12 reported a rate of success of 25% with this technique in 1977. Their approach was “radical debride- ment of all necrotic debris and removal of the prosthesis, where the components were loose or bone involvement was present. The patients were treated with irrigation with an appropriate antibiotic and were maintained on high doses of parenteral antibiotics for as long as possible”. 12 Coventry advocated “clo- sure over tubes” to encourage drainage. 11 With further reports, factors thought to improve treatment included onset of PJI within the first four post-operative weeks, 13 debridement initiated early after the onset of symptoms of infection, 14 the absence of a sinus tract or radiographic signs of loosening 15 and the type, duration, and route of antibiotic treatment. 16-19