Review of Recent Advances in Managing Periprosthetic Joint Infection After Total Knee Arthroplasty: DAIR Technique

Introduction

The use of prosthetic knee implants has increased due to greater life expectancy and the need for improved mobility among elderly patients. Arthroplasty procedures are generally safe and effective, playing a critical role in symptom relief and functional restoration. However, this rise in procedures has been accompanied by an increase in PJI.¹ The incidence of PJI following primary total knee arthroplasty (TKA) is approximately 1.08% across various regions² and ranges between 5.6% and 35.0% after revision surgeries.³

Although multiple definitions of PJI have been proposed, none have achieved universal acceptance.^4–7 This lack of standardization introduces bias when comparing data across studies and hinders the development of consistent diagnostic and treatment protocols. Additionally, the continuous emergence of new biomarkers and diagnostic technologies renders some existing definitions outdated.⁷

In response, a new definition was introduced in 2021 by the European Bone and Joint Infection Society (EBJIS), incorporating recent research insights while maintaining elements of previous definitions.^8. Various treatment strategies have been suggested for managing PJI.

In the management of early or acute PJI cases, the use of DAIR is recommended as a joint-preserving alternative. This approach is particularly advantageous as it reduces the morbidity associated with the removal of implants.⁹ DAIR demonstrates highly variable success rates, which are influenced by several factors, including the timing of intervention, the causative pathogen, the patient’s overall health status, and the surgical technique used.^10,11 It is important to mention that the selection of antibiotics plays a crucial role in outcomes.¹² Recently, the modified DARPI method has been introduced as a safer option for treating early acute periprosthetic joint infections. This innovative approach enhances the success rate of treatment outcomes.¹³ There are certain limitations associated with the use of Dair in cases of chronic infections, particularly due to the high rates of failure observed. In these circumstances, two-stage revision continues to be regarded as the gold standard treatment.¹⁴ This review discusses current evidence regarding the DAIR approach, focusing on its indications, clinical outcomes, and limitations. It further explores prognostic factors, antibiotic regimens, and recent surgical innovations.

Definition

Many medical societies have developed “diagnostic criteria” to improve the accuracy of the diagnosis of PJI (Table 1).

Table 1 Comparison Between Some Diagnostic Criteria, Recently Developed Between 2011 and 2019

The latest criteria were defined by the European Bone and Joint Infection Society (EBJIS) in 2021. The EBJIS 2021 definition of periprosthetic joint infection (PJI) is widely regarded as a major improvement over earlier diagnostic criteria because it resolves many of the limitations that existed in previous frameworks and emerged from a collaboration between EBJIS, EANM, ESR, and infectious disease experts. Its strength lies in being more sensitive, more clinically practical, and more realistic about the complexity of PJI, especially low-grade and biofilm-mediated infections.it integrates a broader range of diagnostic tools: It combines clinical signs, serum markers (CRP, ESR, D-dimer, IL-6), a wide range of synovial tests (WBC count, PMN%, leukocyte esterase, α-defensin, synovial CRP), advanced microbiology including prolonged cultures and implant sonication, histopathology, and even nuclear imaging techniques such as WBC-labelled scintigraphy and PET/CT. Provides a graded (3-tier) interpretation instead of a binary one, and recognition That No Single Test Has Perfect Accuracy.⁸

They Classified Infections into

• Infection Unlikely: Generally indicated when all diagnostic findings are negative.
• Infection Likely: Typically requires two positive findings, one of which must be a positive clinical feature or raised C-reactive protein. The second one is another positive test from synovial fluid, microbiology, histology, or imaging.
• Infection Confirmed: Can be established by a single strong positive finding in several categories, such as purulence, high synovial fluid leukocyte counts, positive alpha defensin, multiple identical positive cultures, or specific histological/imaging results.

These guidelines emphasize that cautious interpretation of results should be carried out if other inflammatory conditions are present and if prior antibiotic use can affect microbiological tests. They also advise careful consideration of single positive cultures or low sonication counts alongside other evidence. Specific conditions also apply to certain tests, like alpha defensin, synovial fluid analysis, and sonication.⁸ These criteria are helpful as diagnostic tools and as guides for decision-making procedures.

Classification of Infection

In the literature, many classification systems categorize PJI according to the timing of the infection:¹⁵

The Coventry system classifies PJIs into early infections occurring within 1 month. Infections occurring between 1 and 24 months and late infections occurring more than 24 months after the primary total knee arthroplasty (TKA).

The International Consensus Meeting ICM system divides PJIs into early (within 90 days since primary TKA) and late (more than 90 days since primary TKA) infections.

The Auckland system distinguishes between early (less than 1 year) and late (more than 1 year) PJIs.

The Tsukayama system PJIs are categorized as follows: early if they occur within the first month, acute haematogenous if they occur after one month with symptoms lasting less than seven days, and chronic if symptoms persist for more than seven days.¹⁵

Treatment

The objectives of treating infected knee prostheses are to eliminate infection, alleviate pain, and enhance joint function.¹⁶ The choice of treatment depends on several factors: The timing of the infection (whether it is early/acute or late/chronic), the responsible microorganism, the status of the adjacent soft tissues, the implant’s stability, the surgeon’s skill, and the patient’s overall health and functional abilities. Furthermore, considering the presence of systemic infection symptoms and the patient’s willingness or ability to undergo multiple surgical procedures is crucial in determining the most appropriate management method.^11,17

Treatment options differ from DAIR to prosthesis replacement, either in two stages (which is the most commonly used technique) or in a single stage, and in rare and extreme cases, arthrodesis or even amputation.⁵

The Indications of DAIR

In 2013, the International Consensus of Periprosthetic Joint Infection¹⁸ Considered DAIR to be a valid option for acute early postoperative infection (< 4 weeks after surgery). It is used especially in the period when biofilms are still immature and susceptible to antibiotic treatment. This evidence was supported by two recent studies in 2021 and 2024.^19,20

This technique can be used in late acute haematogenous infection, especially in individuals who have a stable and well-functioning prosthesis, with no evidence of infection seen in radiographs, and with a favorable soft tissue envelope without any fistula.²¹ These indications are supported by an updated systematic review in 2024 by Longo et al²⁰ and by many other papers.^11,21–24 Manning et al²⁵ recommended that more randomized controlled trials are needed to draw firm conclusions, as the results vary significantly between studies, and the success rate ranges between 41% and 92%.

It is worth mentioning that many papers showed no differences in implant retention rates between single or double DAIR,^26,27 implying that an additional debridement provides minimal extra advantages. We introduced an algorithm to illustrate the eligibility for the DAIR technique. (Figure 1).

Figure 1 A flowchart illustrating the eligibility criteria for DAIR treatment.

Prognostic Factors

Factors Associated with Treatment Success

By analyzing 21 papers between 2018 and 2025 (Table 2), we could find that many prognostic factors associated with successful DAIR Outcomes should be taken into account. They can be summarized as follows:

Table 2 Analysis of 21 Papers About the Results of DAIR and Factors Affecting the Results

• Timing and Presentation: Early intervention in the postoperative period (within the first 4 to 6 weeks) and a shorter duration of symptoms before debridement are linked to successful outcomes.^9,28
• Surgical and Institutional Factors: The expertise of the surgical team plays a critical role, with fellowship-trained arthroplasty surgeons demonstrating higher success rates in managing infections.⁴¹ Successful outcomes are strongly associated with meticulous debridement and the exchange of modular components, such as the polyethene liner.^21,33,35 Additional techniques that enhance treatment efficacy include combining DAIR with muscle flap procedures.,³⁴ meticulous surgical debridement (aided by methylene blue), delivering local antibiotics through vancomycin beads or calcium sulfate, and performing surgical synovectomy.³⁶
• Patient and Host Factors: Success is more likely in younger patients with good physiological status (eg, higher serum albumin) and no significant comorbidities. DAIR shows a higher success rate in the hip than in the knee.⁹
• Biomarkers and Scoring Systems: A low KLIC score³⁹ High synovial fluid glucose levels (>44 mg/dL), a low serum-to-synovial glucose ratio predict successful outcomes.,⁴² strictly standardized culture protocol and high pathogen ID rate with advanced diagnostics (mNGS).³¹

Factors Associated with Treatment Failure

• Infection Characteristics: Timing and nature of the infection are key predictors of failure. Late-acute, chronic PJI presentations⁹ or acute hematogenous,⁴¹ and the type of the infecting pathogen, especially MSSA or MRSA, are critical negative factors.^9,29,35,36
• Patient or Host Factors: Patient frailty and comorbidities increase failure risk, including age over 80, male gender, and smoking. In addition to conditions like chronic kidney disease, liver cirrhosis, rheumatoid arthritis, and COPD. High-risk patients can be identified using objective criteria, such as a high KLIC score.³⁹ The fracture as the indication for arthroplasty also augments this risk.^28,35
• Biomarkers and Scoring Systems: elevated systemic inflammatory markers such as C-reactive protein (CRP > 150 mg/L)³⁵ Adverse local biomarkers, like low synovial fluid glucose levels, are strong indicators of potential treatment failure.⁴²
• Treatment Factors: Not allowing modular component exchange during the DAIR procedure.³⁵ And multiple previous joint surgeries.³⁴ Increases the risk of a poor outcome. On the other hand, pathogen-oriented antibiotic therapy²² and a combination of rifampin with a fluoroquinolone³⁵ Have a positive impact on the results.

Thus, according to all these factors, we can conclude that making careful patient selection and adherence to strict protocols is crucial for achieving optimal outcomes. These results are supported by many review papers that are summarized in Table 3.

Table 3 Summary of 4 Recent Review Papers

Surgical Technique (Debridement, Irrigation, and Implant Replacement)

It is recommended to aspirate the knee and collect fluid for culture immediately after making the skin incision to prevent contamination during the procedure. If sufficient fluid is obtained, the samples are divided into three parts: one sterile container for microscopic examination, cell counting, and culture, and two blood culture bottles for aerobic and anaerobic cultures.⁴⁴

The first step is always the debridement.

This surgical procedure encompasses the removal of skin margins, excision of any sinus tracts, radical synovectomy, and the exchange of removable implants. It is essential to remove the polyethylene tibial insert to facilitate access to the posterior aspect of the joint.⁴⁵ This procedure should be performed with an open arthrotomy. It is crucial that all damaged or devitalized tissues and bones, including scar tissue, sinus tracts, osteolytic areas, sequestra, and other non-viable tissues, are excised until healthy bleeding margins are achieved.¹¹

Irrigation must be the next step. Specific protocols are in place. The wound should be thoroughly irrigated with 6 to 9 liters of normal saline until the fluid becomes clear. Additionally, the knee should be soaked for five minutes in a 2% aqueous chlorhexidine solution.⁴⁴

Despite decades of use, there is still no high-quality evidence demonstrating that higher volumes, particular antiseptic concentrations, or even the use of antiseptic solutions at all lead to superior clinical outcomes. This underscores a fundamental problem: much of the current approach is driven by expert opinion rather than validated clinical efficacy.

The 2022 review by Caid et al⁴⁶ highlights a significant gap in the existing evidence. Although they examined a wide range of antiseptic irrigants— including povidone-iodine, chlorhexidine, hydrogen peroxide, acetic acid, antibiotic solutions, taurolidine, and polyhexanide—the review ultimately revealed that the current studies are inconsistent, methodologically flawed, and poorly controlled. Their inability to recommend a preferred solution does not indicate that all solutions are equivalent; rather, it reflects the inadequacy of the available evidence.

Attempts to introduce new solutions, such as Bactisure^®, have not yet resolved these uncertainties. The retrospective cohort published by Andriollo et al⁴⁷ (2024), while reporting an 87.2% infection-recurrence-free survival rate, offers limited scientific value due to its inherent design weaknesses. Without randomization, blinding, or standardized control groups, it is impossible to discern whether the observed outcomes are attributable to the solution itself or to confounding variables—such as surgical expertise, host factors, or selection bias.

The randomized trial protocol outlined by Oleo-Taltavull et al.⁴⁸ Signifies progress in theory; however, we cannot assume that Bactisure^® or any other proprietary agent is superior to simple saline until the results are published and critically evaluated. Given the commercial interests linked to biofilm-targeting technologies, it is essential to interpret such trials with caution, focusing on potential conflicts of interest, funding sources, and the rigor of the methodology.

Antibiotics

The Type of antibiotics

An empirical antibiotic regimen must be administered following thorough debridement. Once definite microbiology results are available, antibiotic therapy is changed to a more specific therapy.⁴⁹ Antibiotic treatment depends on the specific type of pathogen, its susceptibility to antibiotics, and the type of surgery performed.^49,50

Studies show that the debate over the benefits of rifampicin in treating staphylococcal PJIs remains ongoing^50–52 (Table 4). Its effectiveness is influenced by the treatment duration,⁵³ and in combination with certain antibiotics like fluoroquinolones.^12,54 A short-term treatment strategy generally yielded better results.⁵⁵ Rifampicin efficacy seems highest when combined with a fluoroquinolone, and its benefit may be more pronounced in knees than in hips.⁵¹

Table 4 Recent Systematic Reviews Showing the Efficacy of Rifampicin Use

However, the evidence quality is limited due to the nature of the studies, indicating a need for more rigorous research on rifampicin’s optimal use in these infections (Table 5).

Table 5 The Role of the Duration of Rifampicin in PJI Treatment

Duration of Antibiotics

After performing debridement, irrigation, and inserting the prosthesis, pathogen-specific intravenous antibiotic therapy is recommended for 2–6 weeks. This should be combined with oral rifampin 300–450 mg twice daily. Following this initial treatment, patients should continue taking rifampin along with a complementary oral medication for 6 months.⁵ There is an ongoing debate in the medical community about the optimal length of antimicrobial treatment after DAIR.⁵⁷ In 2024, Chao R and colleagues⁵⁸ Conducted a cohort analysis on extended antibiotic treatment for PJI failure in TKA. They found that a year of extended treatment significantly reduced PJI failure risk compared to the standard 6-week course, with benefits plateauing after one year. There were no significant differences in adverse event rates between the two groups.

Recent studies indicate that there is limited support for the use of suppressive antibiotic therapy (SAT) in treating periprosthetic joint infections. The outcomes appear to be similar whether SAT is maintained or discontinued^59,60 Overall, the quality of the evidence is low. The average rate of side effects from long-term antibiotic use is 15.4%.⁶¹ Highlighting the need for more robust, high-quality research in this field.

A key question is: If DAIR fails to eradicate the infection, does this jeopardize the success of later staged revision procedures? The answer is controversial. J. Christopher Sherrell et al⁶² found that failed DAIR can negatively affect outcomes in two-stage revision TKA, while K. Kim et al⁶³ reported no difference in success rates for subsequent staged revisions following a failed DAIR. Therefore, the potential benefits of a successful DAIR procedure must be carefully balanced against the possible risks associated with treatment failure.²¹

Debridement, Antibiotic Pearls, and Retention of the Implant DAPRI

In 2019, Calanna et al proposed some modifications to the surgical technique of DAIR.⁵⁷ They invented debridement, antibiotic pearls, and retention of the implant by adding antibiotic pearls (DAPRI) to improve the chances of saving an infected total knee replacement, and to eliminate bacterial biofilms. It could be a safer option for treating early acute periprosthetic joint infections, improving the success rate. This finding is consistent with a recent systematic review.¹³

Limitations

While the DAIR is a suitable option for treating PJI following TKA, it has some limitations. Specifically, it requires a strict and narrow window for intervention in cases of early and acute infections, and it has a high failure rate when used for chronic infections.^9,43

The effectiveness of this approach also depends on the specific microorganisms involved²¹ as well as patient health and host factors.^9,39 These considerations may lead clinicians to depend on revision exchange in some circumstances.¹⁴

Although DAIR is considered a “less invasive” option and has lower initial costs compared to two-stage revisions, total costs may increase if further treatments become necessary after a failure.⁶⁴

Functional outcomes and quality of life are now key metrics of success in DAIR procedures. By preserving the prosthesis and minimizing soft-tissue disruption, successful DAIR leads to faster recovery, earlier ambulation, and better knee mobility. Evidence from Chang et al shows that patients who underwent modified DAIR achieved greater maximal knee flexion (103° vs 90°), improved WOMAC scores (24 vs 30), and higher satisfaction (VAS 8 vs 5) compared to those receiving two-stage revision, with similar infection control rates.⁶⁵

Similarly, Okafor et al found that DAIR generally provides better functional knee scores, reduced morbidity, and a less invasive recovery compared to revision strategies, highlighting the need for strict patient selection to optimize outcomes.⁶⁶

In summary, when DAIR succeeds, it eradicates infection, preserves long-term joint function, and improves postoperative quality of life compared to more extensive revision procedures.

Future Directions

DAIR continues to be a vital treatment option for many acute periprosthetic joint infections, particularly when implemented promptly and for well-chosen patients. While some adjunctive methods, such as the use of rifampin and techniques like DAPRI, show potential, the current evidence remains inconsistent, especially concerning long-term outcomes and the effectiveness of suppressive antibiotic therapy. Future research should focus on developing high-quality evidence for using DAIR in acute periprosthetic joint infection. Large, multicenter prospective studies and randomized controlled trials are essential to establish patient-selection criteria, standardize surgical techniques, and determine optimal intervention timing. Comparative studies should assess long-term outcomes, quality of life, and cost-effectiveness compared to one-stage and two-stage revisions. Investigating pathogen-specific factors, biofilm-disrupting adjuncts, and local antibiotic carriers may enhance treatment protocols. Standardized clinical pathways based on robust data will be crucial for improving outcomes and supporting evidence-based decisions for DAIR candidates.