Article Text

Choice between implants in knee replacement: protocol for a Bayesian network meta-analysis, analysis of joint registries and economic decision model to determine the effectiveness and cost-effectiveness of knee implants for NHS patients—The KNee Implant Prostheses Study (KNIPS)
  1. Elsa M R Marques1,
  2. Jane Dennis1,
  3. Andrew D Beswick1,
  4. Julian Higgins2,3,
  5. Howard Thom2,3,
  6. Nicky Welton2,3,
  7. Amanda Burston1,
  8. Linda Hunt1,
  9. Michael R Whitehouse1,3,
  10. Ashley W Blom1,3
  1. 1Musculoskeletal Research Unit, Bristol Medical School, Bristol, UK
  2. 2Department of Population Health Sciences, Bristol Medical School, Bristol, UK
  3. 3National Institute for Health Research Bristol Biomedical Research Centre, University of Bristol, Bristol, UK
  1. Correspondence to Andrew D Beswick; andy.beswick{at}


Introduction Knee replacements are highly successful for many people, but if a knee replacement fails, revision surgery is generally required. Surgeons and patients may choose from a range of implant components and combinations that make up knee replacement constructs, all with potential implications for how long a knee replacement will last. To inform surgeon and patient decisions, a comprehensive synthesis of data from randomised controlled trials is needed to evaluate the effects of different knee replacement implants on overall construct survival. Due to limited follow-up in trials, joint registry analyses are also needed to assess the long-term survival of constructs. Finally, economic modelling can identify cost-effective knee replacement constructs for different patient groups.

Methods and analysis In this protocol, we describe systematic reviews and network meta-analyses to synthesise evidence on the effectiveness of knee replacement constructs used in total and unicompartmental knee replacement and analyses of two national joint registries to assess long-term outcomes. Knee replacement constructs are defined by bearing materials and mobility, constraint, fixation and patella resurfacing. For men and women in different age groups, we will compare the lifetime cost-effectiveness of knee replacement constructs.

Ethics and dissemination Systematic reviews are secondary analyses of published data with no ethical approval required. We will design a common joint registry analysis plan and provide registry representatives with information for submission to research or ethics committees. The project has been assessed by the National Health Service (NHS) REC committee and does not require ethical review.

Study findings will be disseminated to clinicians, researchers and administrators through open access articles, presentations and websites. Specific UK-based groups will be informed of results including National Institute for Health Research and National Institute for Health and Care Excellence, as well as international orthopaedic associations and charities. Effective dissemination to patients will be guided by our patient–public involvement group and include written lay summaries and infographics.

PROSPERO registration number CRD42019134059 and CRD42019138015.

  • knee
  • adult orthopaedics
  • statistics & research methods
  • health economics

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  • Contributors All authors contributed to the concept and design of the study. EMRM, HT and ADB drafted the article, and JD, JH, NW, AB, LH, MRW and AWB revised it critically for important intellectual content. EMRM and ADB take responsibility for the integrity of the work as a whole, from inception to finished article.

  • Funding This study is funded by the National Institute for Health Research (NIHR) Research for Patient Benefit programme (project reference PB-PG-1013–32010).

  • Disclaimer The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.

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