Start and end dates

2012 - Present



Project summary


Around 100,000 elective hip and knee replacement procedures are performed in England’s NHS each year.  A small but important proportion need to be revised, and joint revision is the standard indicator of the quality of surgery in these low-mortality operations. We followed our work in other specialities on unplanned reoperation (return to theatre) by defining this measure for orthopaedics as it is considered more sensitive to the surgeon’s performance than is revision. By augmenting administrative data with our own surveys, we have also investigated the relation between patient outcomes and both VTE prophylaxis and laminar flow theatres.


  • To explore the utility of return to theatre as a marker of quality of surgical care
  • To evaluate policies aimed at reducing complications


  • Pinder EM, Bottle A, Aylin P, Loeffler MD. Does laminar flow ventilation reduce the rate of infection? An observational study of trauma in England. Bone Joint J 2016;98-B(9):1262-1269 PubMed
  • Bottle A, Aylin P, Loeffler M. Return to theatre for elective hip and knee replacements: what is the relative importance of patient factors, surgeon and hospital? Bone Joint J 2014;96-B(12):1663–8 PubMed
  • Bottle A, Oragui E, Pinder E, Aylin P, Loeffler M. The effect of new oral anticoagulants and extended thromboprophylaxis policy on hip and knee arthroplasty outcomes: observational study Arthroplasty Today 2015;1(2):45–50. ScienceDirect
  • Heidari N, Jehan S, Alazzawi S, Bynoth S, Bottle A, Loeffler M. Mortality and morbidity following hip fractures related to hospital thromboprophylaxis policy. Hip Int 2012;22(1):13-21. PubMed
  • Bottle A, Aylin P, 2006, Mortality associated with delay in operation after hip fracture: observational study, British Medical Journal, Vol: 332, Pages: 947-950, ISSN: 0959-8146  PubMed

Oral presentations

  • Revisions vs return to theatre (Health Sciences Research UK 2015 oral presentation)
  • What is the relative importance of patient, surgeon and hospital on return to theatre following elective hip and knee replacement? (oral presentation International Society for Quality in Healthcare 2014 oral presentation)