Prevention

Host Related

• Question 1: What are the absolute and relative contraindications to elective primary total joint arthroplasty, with respect to SSI and PJI risk?
• Question 2: Is the diagnosis of post-traumatic arthritis associated with increased risks of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs) after joint arthroplasty?
• Question 3: What nutritional markers are the most sensitive and specific for SSI/PJI? Does improvement in nutritional status reduce the risk of SSI/PJI?

Risk Mitigation

• Question 1: What preoperative screening for infections should be performed in patients undergoing revision of hip or knee arthroplasty because of presumed aseptic failure?
• Question 2: Does prior septic arthritis (aerobic, anaerobic, fungal, tuberculosis) of a native joint predispose the patients to an increased risk of subsequent PJI in the same joint receiving arthroplasty? b) If yes, how long after a prior septic arthritis can elective arthroplasty be performed in the same joint?
• Question 3: What indicators/metrics would compel a surgeon to perform resection arthroplasty and antibiotic spacer insertion, delaying the arthroplasty to a later date, in a patient with prior septic arthritis undergoing primary arthroplasty?
• Question 4: Does a prior arthroscopy of the hip joint increase the risks of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs) in patients undergoing elective total hip arthroplasty?
• Question 5: Does a prior arthroscopy of the knee increase the risk of a subsequent surgical site infections/periprosthetic joing infections (SSIs/PJIs) in patients undergoing elective arthroplasty?
• Question 6: Do patients undergoing outpatient total joint arthroplasty have a higher incidence of surgical site infections/periprosthetic joint infections (SSIs/PJIs)?

Antimicrobials (systemic)

• Question 1: What is the most appropriate perioperative prophylactic antibiotic (agent, route, and number of doses) in patients undergoing primary total joint arthroplasty to reduce the risk of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 2: What are the appropriate weight-adjusted prophylactic antibiotic dosages?
• Question 3: Is one dose of preoperative antibiotic adequate for patients undergoing total joint arthroplasty?
• Question 4: Should patients undergoing outpatient total joint arthroplasty receive additional post-operative prophylactic antibiotics?
• Question 5: Does extended prophylactic antibiotics therapy for patients undergoing aseptic revision help reduce the risk of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 6: Should duration and the type of antibiotic prophylaxis be altered in patients with a prior periprosthetic joint infection (PJI)?
• Question 7: Should prophylactic antibiotic therapy be administered for an extended duration in patients admitted to the Intensive Care Unit (ICU)?
• Question 8: Does the use of allografts alter the recommended duration of prophylactic antibiotics?

Antimicrobials (Local)

• Question 1: Is there sufficient evidence to support the use of antibiotic-loaded cement in primary TKA or THA to reduce the risk of surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 2: Is there a role for the use of antibiotic-impregnated cement in primary total joint arthroplasty (TJA)?
• Question 3: What is the optimal antibiotic(s) dosage to be used in cement during reimplantation that does not significantly interfere with the mechanical strength of cement used for fixation?

Operating Room Environment

• Question 1: Does performing a primary total joint arthroplasty after a dirty case (infection or open abdomen) in the same operating room increase the risk of surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 2: Does the use of sterile surgical vests decrease the risk of contamination or incidence of infection following total joint arthroplasty?
• Question 3: Does the use of personal protection suits (space suits) influence the rate of surgical site infections/periprosthetic joint infections (SSIs/PJIs) in patients undergoing joint arthroplasty?
• Question 4: Does changing the drapes during debridement, antibiotics, and implant retention affect the rate of success?
• Question 5: Does the use of separate instruments for each side reduce the rate of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs) in patients undergoing simultaneous bilateral hip or knee arthroplasties?
• Question 6: Does routine use of a new set of surgical instruments and equipment following debridement and before reimplantation reduce the risk of surgical site infections/periprosthetic joint infections (SSIs/PJIs) recurrences? Is it necessary to change all surgical fields before the final reimplantation in septic revision surgery?
• Question 7: Is there a concern for contamination of the surgical field by particles, such as cement, that may escape the wound intraoperatively by coming into contact with the ceiling light or facial masks and fall back into the wound?

Surgical Technique

• Question 1: Does the use of a tourniquet influence the rates of surgical site infections/periprosthetic joint infections (SSIs/PJIs) in primary or revision TKA?
• Question 2: Does the surgical approach (parapatellar vs. subvastus) during primary TKA affect the incidence of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 3: Does the surgical approach of primary THA affect the incidence of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 4: Does the use of periarticular injections affect the rate of surgical site infections/periprosthetic joint infections (SSIs/PJIs) recurrence in reimplantation?
• Question 5: Does simultaneous bilateral hip or knee arthroplasty increase the risk of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs) compared to unilateral or staged bilateral arthroplasty?

Prosthesis Factors

• Question 1: Are there implant materials that mitigate the risk for surgical site infections/periprosthetic joint infections (SSIs/PJIs) after total joint arthroplasty?
• Question 2: Does the type of fixation of an arthroplasty component influence the incidence of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 3: Does the surface (grit blasted, plasma sprayed, porous metal, porous beaded, HA coated) of uncemented THA components influence the rate of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 4: Does the type of bearing surface influence the incidence of surgical site infections/periprosthetic joint infections (SSIs/PJIs) after total hip arthroplasty?
• Question 5: Does the use of modular femoral neck during primary THA affect the risks of subsequent surgical site infections/periprosthetic joint infections (SSIs/PJIs)?
• Question 6: Can implant factors (i.e. type of bearing) influence the thresholds for serum and synovial markers in acute and chronic periprosthetic joint infections (PJIs)?
• Question 7: What can be done with a prosthesis that has been dropped on the floor or allowed to come into contact with a non-sterile portion of the operating room?

Postoperative Issues

• Question 1: Should patients with cellulitis following total joint arthroplasty be treated with antibiotic therapy?
• Question 2: Is undergoing a colonoscopy or upper gastro-intestinal endoscopy after total joint arthroplasty associated with an increased risk of SSI/PJI? If yes, does antibiotic prophylaxis prior to a colonoscopy or upper GI endoscopy after total joint arthroplasty reduce the risk?

Diagnosis

Definitions

• Question 1: What is the definition of a periprosthetic joint infection (PJI) of the knee and the hip? Can the same criteria be used for both joints?
• Question 2: What is the definition of septic arthritis in a native knee?
• Question 3: How can superficial surgical site infections (SSIs) be differentiated from deep SSIs (i.e. periprosthetic joint infections (PJIs))?
• Question 4: How can hip septic arthritis be differentiated from toxic synovitis?
• Question 5: What clinical findings (e.g. fever, erythema, reduced range of motion) are most sensitive and specific for the diagnosis of periprosthetic joint infections (PJIs)?
• Question 6: Should intraoperative purulence be considered as a definitive sign of a periprosthetic joint infection (PJI)?
• Question 7: Is aseptic loosening associated with an undiagnosed periprosthetic joint infections (PJIs)?
• Question 8: Can periprosthetic joint infection (PJI) be assigned a high or low grade? If so, what is the definition of each grade?

Algorithm

• Question 1: Do you agree with the American Academy of Orthopaedic Surgeon’s algorithm for the diagnosis of periprosthetic joint infections (PJIs)?
• Question 2: Are there any contraindications to knee or hip aspiration prior to revision surgery?
• Question 3: In the setting of a dry tap, should lavage with a fluid be performed?
• Question 4: In patients with multiple arthroplasties in place who have developed periprosthetic infections (PJIs) of one joint, should other joints be investigated for PJIs also?
• Question 5: Are point-of-care/rapid tests for diagnosing periprosthetic joint infections (PJIs) validated and useful?
• Question 6: What is the prevalence of culture-negative infections and what are the diagnostic protocols for further investigating these cases?
• Question 7: Do patients with adverse local tissue reactions (ALTRs) have a higher incidence of periprosthetic joint infections (PJIs)?
• Question 8: Should we routinely assess for serum/blood metal levels (cobalt and chromium) when working up a patient with a painful total joint arthroplasty?
• Question 9: How is a periprosthetic joint infection (PJI) diagnosed in the presence of adverse local tissue reaction?

Laboratory Tests

• Question 1: What is an acceptable sensitivity, specificity, negative predictive value, and positive predictive value for a diagnostic tool for periprosthetic joint infections (PJIs)?
• Question 2: Does the presence of both an ESR and CRP below the periprosthetic joint infection (PJI) thresholds rule out the diagnosis of a PJI?
• Question 3: What is the diagnostic accuracy and threshold of D-dimer in the diagnosis of periprosthetic joint infections (PJIs)?
• Question 4: How does the level of leukocyte count and neutrophil percentage in the synovial fluid change with time following total joint arthroplasty?
• Question 5: What is the role of alpha-defensin in the diagnosis of periprosthetic joint infections (PJIs)?
• Question 6: What is the diagnostic accuracy of histologic tests and thresholds used in the diagnosis of periprosthetic joint infections (PJIs)?
• Question 7: What is the role of Specific Granulocyte Counting Methods and New Immunohistologic Staining Techniques in diagnosing PJI?

Pathogen Isolation (Culture)

• Question 1: Should intra-operative cultures be taken during every revision total joint arthroplasty? If so, how many?
• Question 2: Are there significant differences in the yield of culture between pre-operative aspiration and intra-operative culture samples? If so, which result should be utilized?
• Question 3: Do bone cultures provide additional diagnostic accuracy in the diagnosis of periprosthetic joint infections (PJIs)?
• Question 4: Is there a role for obtaining cultures before and at the time of insertion of prosthesis during second stage (reimplantation) of a two-stage exchange arthroplasty?
• Question 5: Should routine cultures be taken in patients undergoing total joint arthroplasty who had a previous open reduction and internal fixation of the same joint (e.g. prior acetabular fracture)?
• Question 6: Is there a role for sonication of implants retrieved during explantation?

Reimplantation

• Question 1: Are the MSIS/ICM criteria valid for decision-making before reimplantation?
• Question 2: What metrics should be considered to determine the timing of reimplantation after two-stage exchange arthroplasty of the infected hip or knee?
• Question 3: Is normalization of serological markers necessary prior to reimplantation arthroplasty performed as part of a 2-stage exchange?
• Question 4: What is the importance of two-week antibiotic holiday prior to reimplantation?
• Question 5: What is the diagnostic accuracy of joint aspiration of a cement spacer in conjunction with clinical evaluation, imaging, serologic tests, and biopsies? Should it routinely be performed prior to reimplantation?
• Question 6: What intra-operative metrics can be utilized at the time of intended reimplantation to help decision-making and reduce the risk of subsequent recurrence?
• Question 7: What is the diagnostic accuracy of frozen section during reimplantation surgery? What thresholds should be used in this context?
• Question 8: Should patients with periprosthetic joint infections (PJIs) caused by Mycobacterium tuberculosis undergo the typical two-week antimicrobial holiday prior to reimplantation?

Pathogen Factors

• Question 1: Does the virulence (low or high) of the infecting organism affect the treatment of acute hematogenous or chronic periprosthetic joint infections (PJIs)?
• Question 2: Is there a difference in the treatment outcome for periprosthetic joint infections (PJIs) caused by a single organism and a polymicrobial PJI?
• Question 3: Is there a difference in the type of pathogens that can cause SSIs/PJIs between hip and knee arthroplasty?
• Question 4: Is there a difference in the organism profile that causes periprosthetic joint infections (PJIs) in different countries?

Fungal PJI

Diagnosis and Treatment

• Question 1: What is the optimal method to diagnose fungal PJI?
• Question 2: Should patients with periprosthetic joint infections (PJIs) caused by a fungus undergo the typical two-week antimicrobial holiday prior to reimplantation?
• Question 3: Can debridement, antibiotics, and implant retention be used to treat acute fungal periprosthetic joint infections (PJIs)?
• Question 4: Which antifungals, route of administration, and duration of treatment should be utilized to treat fungal periprosthetic joint infections (PJIs)?

Treatment

Algorithm

• Question 1: Should early postoperative infection and acute haematogenous infection be treated and managed differently?
• Question 2: Should operative treatment differ in patients with systemic sepsis in the setting of PJI?
• Question 3: What should be done for patients with persistent wound drainage after total joint arthroplasty? What are the indications for surgical intervention?
• Question 4: How should infected bilateral hip or knee arthroplasties be managed?

DAIR

• Question 1: What are the indications and contraindications of using debridement, antibiotics, and implant retention with exchange of modular components for the management of PJI?
• Question 2: Is debridement, antibiotics, and implant retention (DAIR) an emergency procedure for patients with acute PJI or should patient optimization be implemented prior to surgery to enhance the success of this procedure?
• Question 3: Does identification of the pathogen prior to performing debridement, antibiotics and implant retention (DAIR) help guide the surgeon’s decision making? If so, should you wait in a clinically stable patient until the pathogen has been identified?
• Question 4: Does exchange of all modular components during debridement and implant retention (DAIR) reduce the rate of SSI/PJI recurrence?
• Question 5: What is the minimum necessary volume of irrigation solution to use in debridement, antibiotics, and implant retention treatment of acute PJI?
• Question 6: Is there a role for direct intra-articular antibiotic infusion following irrigation and debridement for PJI?
• Question 7: Can debridement, antibiotics, and implant retention (DAIR) be utilized in patients with an acute of chronic infection of a unicompartmental knee arthroplasty (UKA)?
• Question 8: Can debridement, antibiotics, and implant retention (DAIR) be utilized in the treatment of acute PJI with a megaprosthesis?
• Question 9: What factors are associated with the successful treatment of acute PJI using debridement, antibiotics, and implant retention?
• Question 10: Does performing a debridement, antibiotics, and implant retention (DAIR) affect the outcome of a subsequent two-stage exchange arthroplasty?
• Question 11: How many debridement, antibiotics, and implant retention procedure(s) (DAIR) are acceptable in management of patients with acute periprosthetic joint infection of a primary arthroplasty before removal of components needs to be performed?
• Question 12: What is the optimal length of antibiotic treatment following debridement, antibiotics, and implant retention (DAIR) for acute periprosthetic joint infections (PJIs)?
• Question 13: What is the most effective combination of antibiotics in the treatment of acute periprosthetic joint infections (PJIs) caused by methicillin-resistant Staphylococcus aureus (MRSA) that has undergone surgical management with debridement, antibiotics, and implant retention (DAIR)?
• Question 14: What antibiotic therapy (agent, route, dose, and duration) is recommended for Gram-negative acute periprosthetic joint infections (PJIs) being treated with debridement, antibiotics, and implant retention?

One Stage Exchange

• Question 1: What are the potential advantages of a one-stage exchange arthroplasty?
• Question 2: What are the indications and contraindications for a one-stage exchange arthroplasty for the treatment of chronic PJIs?
• Question 3: Is there a role for single-stage exchange arthroplasty in acute periprosthetic joint infections (PJIs of) cementless total hip arthroplasties (THAs)?
• Question 4: Does the morbidity and mortality differ between single-stage and two-stage exchange arthroplasty?

Two Stage – Spacer (Related)

• Question 1: What are the indications for the use of non-articulating vs. articulating spacers during resection arthroplasty of the hip or knee?
• Question 2: What are the indications for interim cement spacer exchange or repeat irrigation and debridement instead of reimplantation?
• Question 3: Should the antibiotics placed in a cement spacer be tailored to the sensitivity of the infective organism?
• Question 4: Which antibiotic(s) should be added to a cement spacer in patients with perirosthetic joint infections (PJIs) caused by multiresistant organisms?
• Question 5: What are the contraindications to using antibiotics in a cement spacer?
• Question 6: Does the use of surgical drains reduce the effectiveness of antibiotic-impregnated cement spacers?
• Question 7: Is there a role for intraoperative autoclaving and re-use of an infected prosthesis as a spacer during resection arthroplasty?
• Question 8: Is it necessary to revise or reduce dislocated articulating antibiotic spacers?

Two Stage Exchange

• Question 1: What is the optimal timing for reimplantation of a two-stage exchange arthroplasty of the hip and knee?
• Question 2: Is it safe to retain a stable cement mantle, for later use, in patients undergoing resection arthroplasty for periprosthetic joint infections (PJIs)?
• Question 3: Should surgeons make an effort to remove cement that has extruded into the pelvis or at difficult anatomical positions in patients with periprosthetic joint infections (PJIs)?
• Question 4: Does the use of non-antibiotic impregnated allograft for bone defects during reimplantation increase the risk of recurrence of SSIs/PJIs?

Surgical Technique

• Question 1: Does arthroscopic surgery have any role in the treatment of acute or chronic periprosthetic joint infection (PJI) of the knee or the hip?
• Question 2: Do all metallic implants need to be removed to eradicate perprosthetic joint infections (PJIs)? Does this apply to other metal hardware present (e.g. hook plates, cables) as well?
• Question 3: Should all knee compartments be resected during resection of an infected unicondylar knee arthroplasty (UKA)?
• Question 4: Can sub-radical resection arthroplasty (leaving parts of implants in place) be considered during management of patients with chronic periprosthetic joint infections (PJIs)?
• Question 5: Is it possible to have an isolated infection of only a portion of the joint (for example the femur and not the acetabulum or tibia and not the femur)?
• Question 6: Should heterotopic ossification (HO) be removed during resection arthroplasty of an infected prosthetic joint?
• Question 7: When soft tissue coverage requires a reconstructive flap, can it be performed at the time of explant or should it be deferred until reimplantation?

Prosthesis Factors

• Question 1: Does the use of cemented or cementless components at the time of reimplantation affect the success of treating chronic PJIs? If yes, what is the optimal antibiotic(s), dosage, and cement to maximize antibiotic delivery and mechanical properties of the cement?
• Question 2: Does the use of tantalum augments during a single-stage revision for periprosthetic joint infection (PJI) influence the rate of subsequent SSIs/PJIs?
• Question 3: Is the use of highly porous tantalum associated with a reduced risks of SSIs/PJIs recurrences in revision total joint arthroplasties?

Salvage

• Question 1: Are there differences in outcomes and survivorship between arthrodesis and above-knee amputations for chronic knee PJIs?
• Question 2: How many exchange arthroplasties are reasonable before a salvage operation (such as amputation or arthrodesis) should be considered?
• Question 3: What are surgical alternatives to hip disarticulation in patients with persistent joint infections?

Antimicrobials

• Question 1: What is the recommended duration of antibiotics after a single-stage exchange for periprosthetic joint infections (PJIs)?
• Question 2: Are there any tests that can guide antimicrobial treatment in patients with PJIs so as to determine when treatment may be discontinued?
• Question 3: Does the International Consensus Group (ICG) agree with the Infectious Diseases Society of America (IDSA) guidelines regarding the recommended duration of antibiotic therapy in orthopaedic infection?
• Question 4: Is the type, dose, route of administration, and duration of antimicrobial treatment influenced by the type of infective organism causing periprosthetic joint infection?
• Question 5: When a patient undergoes aseptic revision and intraoperative culture(s) grow an organism, should patients be treated with antibiotic therapy?
• Question 6: When should rifampin be added to the regimen of antibiotics for management of patients with periprosthetic joint infections (PJIs) undergoing surgical treatment?
• Question 7: What is the optimal antibiotic therapy in cases of culture-negative periprosthetic joint infections (PJIs)?
• Question 8: What antibiotic therapy and duration of treatment should be used in Enterococcal PJIs?
• Question 9: What are the indications for utilizing Fosfomycin, Tigecycline, and Daptomycin, either instead of other antibiotics or in conjunction with other antibiotics for the management of periprosthetic joint infections (PJIs)?

Antimicrobials (Two Stage)

• Question 1: a) What is the optimal length of administration for antibiotic treatment following resection arthroplasty? b) What is the optimal mode of administration for antibiotic treatment following resection arthroplasty?
• Question 2: Does extended oral antibiotic prophylaxis following reimplantation reduce the risk of future failure? If so, what type of antibiotic should be administered and for how long?
• Question 3: When is the optimal time to change intravenous (IV) antibiotic(s) to an oral agent(s) after a resection arthroplasty as part of two-stage exchange?
• Question 4: Can short term (two weeks or less) antibiotic treatment be considered following resection arthroplasty for chronic periprosthetic joint infections (PJIs)?

Antimicrobials (Suppression)

• Question 1: Is there a role for administration of prolonged oral antibiotics following primary total joint arthroplasty?
• Question 2: What is the role of oral suppression antibiotics after reimplantation in patients with negative cultures after 14 days of incubation?
• Question 3: Which patients should be considered for administration of longterm suppressive oral antibiotic instead of surgical treatment in patients with chronic periprosthetic joint infections (PJIs)?

Outcomes

• Question 1: What is the definition of success of surgical treatment of a patient with a periprosthetic joint infection (PJI)? What clinical, operative, microbiological and functional metrics should be considered?
• Question 2: Is there a minimum number of periprosthetic joint infection (PJI) procedures that surgeons should perform annually that qualifies them as experts in the management of PJIs?
• Question 3: What tools (i.e. KLIC score) are available to help predict successful treatment with debridement, antibiotics, and implant retention (DAIR)? What are the accuracy of these tools?
• Question 4: What is the optimal follow-up plan (i.e. schedule, exam maneuvers, labs, imaging) for patients being treated for periprosthetic joint infections (PJIs)? b) How frequently should the inflammatory biomarkers be measured after the resection arthroplasty performed as part of two-stage exchange?
• Question 5: Is there a benefit for the engagement of a multidisciplinary team for the management of patients with periprosthetic joint infections (PJIs)?