Philadelphia 2013: International Consensus Meeting on Periprosthetic Joint Infection

Infection following a joint replacement continues to be a devastating problem for patients and clinicians alike. The prevention, diagnosis and treatment of periprosthetic joint infection (PJI) remains challenging. They drain vast resources and often require lengthy investigation and treatment that obviously has a significant effect on patients’ quality of life. Strategies for preventing infections vary tremendously between different units. Some of the techniques employed to reduce infection rates are based on sound evidence, however some are often born out of tradition and beliefs with little or no scientific evidence to support their use. Its diagnosis has been no less challenging. There have been great strides towards developing criteria for the diagnosis of PJI. The Musculoskeletal Infection Society (MSIS) in conjunction with the Centre for Disease Control (CDC) convened a 21-member work group, on the 4^th August 2011, to formulate a definition for PJI (1). They were of the opinion that PJI can be confirmed if there is a sinus that communicates with the prosthesis, if a pathogen is isolated via culture from two separate tissue or fluid samples, or the presence of four of the following six criteria:

Total hip replacement is one the most effective interventions in modern medicine (2). Infection is a catastrophic complication of joint replacement surgery. Worldwide it affects thousands of patients and drains vast amounts of ‘resources within health care services. Its cost is clear to see in terms of morbidity to patients and their families’ lives. There is also a financial and resource burden on health care services. The investigations required are numerous and expensive. The surgery is time consuming; the implants and antibiotic choices are often expensive. The aftercare in terms of monitoring and rehabilitation also needs to be considered. There are still components of its diagnosis and treatment that remain elusive and there are several unanswered questions that demand our urgent attention. It is well recognised that conclusive clinical research that would produce definitive answers is not always possible. This can be due to the large numbers that would be necessary to determine a significant difference or where the clinical end point is subjective. For example, although PJIs represent a very serious problem for patients and surgeons, the rate following arthroplasty is low, often reported to be between 0.5-2% (3), it would therefore take thousands of patients to determine differences between different prophylactic antibiotics. There are many more unanswered questions. What are the optimal choices and quantities of antibiotics in cement? What is the best time interval between 1^st and 2^nd stages for infected revisions? How many irrigations and debridements should be performed? What type of laminar airflow should be used? Are exhaust suits beneficial? What skin preparation should be used? These are just a few of the dilemmas that revision arthroplasty surgeons face.

In order to answer and guide clinicians interested in the management of PJI, the International Consensus Meeting on Periprosthetic Joint Infection was organised. This was hosted at the Rothman Institute at the Thomas Jefferson University in Philadelphia, Pennsylvania, USA. The meeting was co-chaired by Professor Javad Parvizi and Professor Thorsten Gehrke. The dialogue involved a multidisciplinary approach, with delegates from many subspecialties, who had vested interests in PJI, involved. Members of each work group held online meetings over a 10-month period. This involved the expertise of 400 delegates from 51 countries. A total of 31 discussion pages were developed, there were a total of 25,196 pages viewed and over 23,500 emails exchanged. The topics discussed were: patient preparation; medical optimisation; prophylactic antibiotics; operating theatre environment; prosthesis selection; blood conservation; diagnosis of PJI; spacers; wound management; the role of irrigation and debridement; single- and two-stage revision surgery; prevention of late PJI; and atypical PJI.

In particular the collaborative efforts of the MSIS and European Bone and Joint Infection Society (EBJIS) should be noted. It has been their mission to improve the outcome of patients with musculoskeletal infection. A preliminary draft of the consensus statement was produced and on the 31^st of July and 1^st August 2013 a forum of 342 delegates from 80 countries and over 50 different societies convened in Philadelphia to finalise the consensus statement. This began with a series of face-to-face discussions to iron out any discrepancies, adjust the finer details and finalise the documentation. The delegates assembled to vote on the 207 statements using an Audience Response System. This was used to record the strength of the consensus.

The statement was generated under the guidance of ‘Dr William L. Cats-Baril, a world expert in the generation of consensus documents, using the Delphi Method. This document encompasses an immense body of work, and represents the numerous stakeholders who are interested in reducing the burden of PJI.

It’s implementation will hopefully act as a guide to clinicians, assist in the decision making process and most importantly enhance patient care. Clinicians who are engaged in the management of PJI are encouraged to read the statement in full (4).