Infection after total knee arthroplasty (TKA) is a difficult complication to manage. Infection rates after primary TKA and revision TKA range from 0.5%-2% and 2%-4%, respectively. The results of several population studies suggest that infection is more likely to occur after TKA, which in turn is one of the most common causes of TKA failure.
The key factor in reducing the risk of infection remains prevention, but there is a lack of sufficient evidence-based research literature to develop optimal preventive measures. Every case of TKA that presents with pain should be suspected to be possibly due to infection and requires further investigation until this possibility is ruled out. The management plan for these cases should include detection of the presence of infection by standard laboratory screening.
Articular synovial fluid aspiration remains the best method for diagnosing infection. If the synovial fluid has a white blood cell count greater than 1,700/μL and a neutrophil classification greater than 69% the possibility of infection should be highly suspected.
There are several options available for the treatment of deep periprosthetic infections. The timing of the onset and onset of symptoms associated with the procedure is a critical factor in determining the successful management of TKA infections.
The retained prosthesis management option can only be applied in cases of acute infection, but recent results in the literature suggest that the success rate of this option is extremely low, which has led to doubts about its role in the management of infected TKA. In contrast, the staged revision and replacement prosthesis protocol remains the gold standard for the management of postoperative TKA infections.
Instr Course Lect 2013;62:349-361.
Infection remains one of the most difficult complications to manage after TKA. The overall incidence of infection after initial and revision TKA has been reported in the literature to range from 0.5%-2% and 2%-4%, respectively. 16.8% of all revision TKA cases were performed due to postoperative infection in 2005.
It is estimated that by 2030, 65% of revision TKAs will be due to infection, which corresponds to approximately 52,000 cases of infected TKAs. Managing these infected TKA cases will be a significant financial burden. Due to the long hospital stays and high complication rates, it costs approximately $60,000-$100,000 per case of infected TKA. Treatment of infected TKA is one of the most resource-intensive of all orthopedic procedures.
In this article, we will focus on the diagnosis and treatment of infected TKA.
The diagnosis of TKA infection includes plain radiographs, laboratory tests, arthrocentesis aspiration, advanced imaging techniques, and intraoperative testing, among other relevant tools that can assist in the diagnosis of suspected infected TKA. However, there are currently no relevant criteria for the diagnosis or perioperative management of suspected periprosthetic infections.
Recently, the American Academy of Orthopaedic Surgeons (AAOS) Task Force evaluated the evidence for each of the existing diagnostic options and, on this basis, proposed a new protocol for the diagnosis of TKA infection. (Figures 1 and 2) Figure 1 Flow chart for the diagnosis of periprosthetic hip and knee infections with a high probability. a, If the possibility of infection exists and the results of the first joint cavity aspiration culture are biased, a repeat aspiration may be performed. b, If the diagnosis of infection is still not established at the time of surgery, frozen section examination may be performed and intraoperative sorting counts of synovial fluid WBCs may also be performed. c, Nuclear imaging form. Leukocyte tracer imaging combined with bone or bone marrow imaging, 18F-deoxyglucose positron emission computed tomography (18F-FDG-PET) or leukocyte tracer imaging, etc. (Reprinted from Della Valle C, Parvizi J, Bauer T, et al: AAOS Clinical Practice Guideline Summary: Diagnosis of Preprosthetic Joint Infection of the Hip and Knee. J Am Acad Orthop Surg 2010;18(12):760-770.) Figure 2 Flow chart for the diagnosis of periprosthetic infection of the hip and knee with a low probability. a, if there is a probability of infection and the results of the first arthrocentesis aspirate culture are biased, a repeat aspirate may be performed. b, if the diagnosis of infection is still not established at the time of surgery, a frozen section may be performed and intraoperative (Reprinted from Della Valle C, Parvizi J, Bauer T, et al: AAOS Clinical Practice Guideline Summary: Diagnosis of Preprosthetic Joint Infection of the Hip and Knee. J Am Acad Orthop Surg 2010;18(12):760-770.) The most important task in the diagnosis of infected TKA is first to take a detailed history and perform a careful physical examination. In general, every case of postoperative pain after TKA should be suspected to be due to infection until it is confirmed that it is not. The location of the pain and its characteristics need to be noted. Involvement pain from the hip joint as well as the lumbar spine must be excluded. The exact timing of the onset of pain should also be determined.
It is important to know whether the pain persists from the time of surgery or whether it reappears after a period of time after surgery when the pain has disappeared. Does the degree of pain vary with activity level? Is there any warmth or redness around the knee joint? Are there any problems with wound healing or oozing after the initial surgery? Has the patient previously been treated with antibiotics for suspected infection, and has the patient undergone operations after TKA that could lead to bacteremia, such as management of a dental lesion, colonoscopy, or a transurethral operation?
X-rays can provide useful information in diagnosing infection, and it is often helpful to compare X-rays taken in the immediate postoperative period with those taken at the most recent review. If infection is present, x-rays may show periosteal delamination, subchondral bone resorption, progressive translucent lines, or focal bone resorption. It is important to note, however, that typical foci of bone resorption and osteolysis may be observed only when bone loss reaches 30%-50%.
Hematologic analysis should include white blood cell (WBC) counts, sedimentation (ESR), C-reactive protein (CRP), and more recently, interleukin-6 (IL-6) levels have been added. It should be remembered, however, that no test is 100% sensitive for diagnosing infection. The AAOS Task Force recommends that ESR and CRP levels be measured at the initial visit in all cases of suspected infection.
A complete blood WBC count is not a reliable indicator of TKA infection. Studies have shown that WBC counts are normal in up to 70% of infected cases. The ESR usually peaks at 5-7 days postoperatively, then slowly decreases and reaches normal levels after about 3 months. CRP levels begin to rise within 6 hours postoperatively, usually peak at 2-3 days postoperatively, and then decrease to normal within 3 weeks.
The specificity of ESR and CRP for infection is only 56%, and their abnormalities alone or together are not sufficient to diagnose infection. However, simultaneous use of both is more accurate in ruling out the possibility of infection, with a sensitivity of 96% and a negative predictive value of 95%.
The use of serum IL-6 levels to determine the presence of infection has recently become common. It usually peaks within 6 hours postoperatively and decreases to normal within 72 hours postoperatively. Studies have shown that IL-6 has a sensitivity and specificity of 100% and 95%, respectively, when used to predict infection. However, IL-6 testing is not currently available at all medical facilities.
Arthrocentesis aspiration remains one of the most effective methods for diagnosing infections, but it is also associated with false-negative results. To minimize false-negative bacterial culture results, patients should be off antibiotics for 2-3 weeks prior to arthrocentesis Patients who have recently used antibiotics may still receive arthrocentesis for cell counting and sorting if necessary, but bacterial culture will no longer be reliable.
Mason et al. found that a WBC count greater than 2,500 cells/μL and a neutral sorting ratio greater than 60% had a sensitivity and specificity of 98% and 95%, respectively, for predicting infection, with a positive prediction rate of 91%.
Leone and Hanssen reported a negative prediction rate of 98% for excluding infection when the joint fluid WBC count was less than 2,000/μL and the neutral classification was less than 50%.
Newer literature suggests different ranges of WBC count values and neutral classification ratios to diagnose periprosthetic infections. In general, if the synovial fluid WBC count is greater than 1,760/μL and the neutral classification ratio is greater than 69%, the possibility of infection should be highly suspected.
Due to the body’s response to surgical stimuli, synovial fluid cell counts and sorting ratios may be elevated in the early postoperative period, which may not accurately reflect the presence of infection. Therefore, if traditional cell counts and sorting ratios are used as criteria to diagnose infection in the early postoperative phase, special attention needs to be paid to the fact that abnormalities in these indicators may lead to unnecessary surgery.
Bedair recently conducted a study using synovial fluid testing to diagnose early infection after TKA. They performed knee puncture aspirations in 146 patients within 6 weeks of TKA, resulting in a diagnosis of infection in 19 patients. After determining the appropriate cutoff point by subject operating characteristic curve (ROC), these investigators concluded that a synovial fluid WBC count of 27,800/μL had a positive and negative predictive rate for infection of 94% and 98%, respectively, while the optimal cutoff level for neutral classification ratio was 89%.
Radionuclide scans may be useful in diagnosing infection, especially in ambiguous cases; however, these tests are expensive, cumbersome for patients, and lack specificity for infection.
Tc-99m detects osteoblast activity, and although positive results can be obtained in cases of infection, they may also yield positive results in cases including trauma, degenerative joint lesions, and tumors. More importantly, the Tc-99m scan may remain positive even at 12 months postoperatively, with a sensitivity and prediction rate of only 30% to 38%.
In-111-labeled leukocyte scans can show nucleolar concentrations in areas where WBCs are present. The sensitivity and specificity of the assay were 77% and 86%, respectively. Combining the results of both nuclear scans improves the specificity of predicting infection, and therefore simultaneous examination of both scans is generally recommended.
More recently, there has been increasing interest in the use of molecular genetic techniques to diagnose infection, including multimerase chain reaction analysis of ultrasound wash samples from prostheses. Most of these techniques yield results within 4-6 hours and are effective in the presence of antibiotics.
The disadvantage of molecular genetic detection of infections is that they do not provide drug sensitivity results for bacteria. They are also more complex and expensive to perform, and the high sensitivity of these tests can lead to false-positive results.
Intraoperative detection methods include Gram staining and frozen section histology. In general, Gram staining is unreliable and has a very low sensitivity, and Gram staining results alone should not be used to rule out infection. the AAOS working group recommended against Gram staining to rule out periprosthetic infection.
The literature reports variable results in the diagnosis of infection on frozen section histology, and the accuracy of diagnosis is technically dependent, often relying on the experience of the pathologist performing the observation to determine the presence of acute infection. Sampling errors often occur when performing frozen section examinations. Different assays have shown that the presence of 5-10 WBCs per high-powered field of view is sufficiently sensitive and specific to diagnose infection.
The AAOS Working Group strongly recommends frozen section histology of periprosthetic tissue during revision TKA where infection has not been confirmed or ruled out preoperatively. However, because of the limited information available in the literature, the AAOS Working Group was unable to determine the optimal standard value for WBCs (5 or 10 WBCs observed per high magnification field of view).
New methods for diagnosing infection Although there are many methods available for the diagnosis of suspected periprosthetic infections, there is not yet an accepted and effective diagnostic protocol. Recently, a working group of the Bone Muscle System Infection Society analyzed all currently available evidentiary information and proposed a new definition of periprosthetic infection. These criteria should allow clinicians to broadly adopt the definition of relevant periprosthetic infections.
Based on the criteria proposed by the working group, a periprosthetic infection is considered to be present if there is.
(1) a sinus tract communicating with the joint cavity; (2) the same pathogenic organism is obtained on two separate cultures of tissue or fluid specimens collected from the diseased joint; and (3) four of the six criteria are met.
These 6 criteria included elevated ESR or CRP levels, elevated synovial fluid leukocyte count, elevated synovial fluid leukocyte ratio, presence of pus in the diseased joint, isolation of pathogenic microorganisms from tissue or joint fluid specimens, and greater than 5 neutrophils in all 5 high-powered (×400) fields of view during microscopic examination of frozen sections of periprosthetic tissue.
Surgical management of infected TKA includes antibiotic treatment with retention of the prosthesis, open debridement and irrigation with replacement of the polyethylene liner, and removal of the prosthesis. Removal of the prosthesis may include arthroplasty, fusion, primary revision replacement, secondary revision replacement, or amputation.
Many factors are involved in the selection of a management plan, including the depth and timing of infection, the condition of the periarticular soft tissue, the fixation of the prosthesis, the type of causative organism, the ability of the host to resist infection, the availability of medical resources to the physician, and the expectations of the patient.
Tsukayama et al. classified infected TKA into 4 types.
Type I infections are characterized by positive bacterial culture results at the time of surgery; Type II refers to early infections that occur within the first month after surgery; Type III refers to acute hematogenous infections that occur late after TKA with a symptom duration of less than 4 weeks; and Type IV infections refer to chronic infections that occur late after surgery with a symptom duration of more than 4 weeks.
Table 1 details the components of this staging, as well as the recommended management protocols corresponding to each staging.
Table 1 Staging of periprosthetic infections Antibiotic treatment without surgical debridement and antibiotic treatment only is indicated only in cases that are too debilitated to tolerate surgery. In addition, the following conditions should be met: the causative organism should be a low virulence bacteria, the patient should be stable, the prosthesis should be fixed and stable, and appropriate oral antibiotics should be available. The success rate of antibiotic-only treatment of infected TKA without surgical debridement has been reported in the literature to be approximately 20%.
Open debridement and irrigation It is generally agreed that surgical open debridement and irrigation should be performed in cases of acutely infected TKA. In contrast, an irrigation and debridement with prosthesis retention regimen has a high failure rate in the management of chronic TKA infections (signs and symptoms lasting longer than 4 weeks) and should not be considered.
Arthroscopic debridement Arthroscopic debridement and debridement is considered a good and attractive alternative to open debridement. This method allows manipulation through a very small arthroscopic access and therefore is less invasive to the soft tissues. However, the literature is sparse and the sample size of cases is small.
Waldman et al. performed arthroscopic debridement and irrigation in 16 cases of acute infection with less than 7 days of symptom onset, resulting in successful treatment of 38% of infections at an average follow-up of 56 months, and Dixon et al. reported in their 2004 study that 15 patients were successfully cured of 60% of infections at an average follow-up of 55 months after arthroscopic debridement.
In addition to the limited efficacy data, there are other concerns about arthroscopic irrigation debridement. Because only a limited amount of the bone-cement interface and prosthetic surface can be examined through arthroscopy, it does not provide as thorough an examination of intra-articular lesions as open surgery. Also, the polyethylene liner cannot be replaced, which in turn limits the cleaning of the posterior aspect of the knee. This also does not allow for complete removal of synovial tissue.
Likewise, it is difficult to remove the debris tissue removed through the narrow arthroscopic working channel. For these reasons, and because the literature reports less than stellar outcomes, arthroscopic irrigation and debridement for infected TKA can only be performed in rare cases.
Open debridement and irrigation The literature reports variable results for open debridement and irrigation for periprosthetic infections (Table 2). We reviewed more than 20 published publications on the subject and found that success rates for this treatment modality ranged from 19% to 83%, but most studies had success rates of less than 60%.
Table 2 Summary of literature on irrigation debridement for acute periprosthetic infections Silva et al. evaluated 530 cases of acute periprosthetic infections that underwent open surgical debridement debridement in a meta-analysis conducted in 2002. The study included all cases of early acute postoperative infection and late acute hematogenous infection. The results showed an overall success rate of 33.6%.
There are clearly multiple variables such as timing of the procedure, the patient’s own risk factors, surgical technique, and the causative organism that influence the outcome (Table 3).
Table 3 Risk factors for failure after irrigation debridement and polyethylene liner replacement for infected TKA When managing infected TKA by irrigation, debridement, and polyethylene liner replacement, the timing of the procedure may be a critical factor in the success of treatment. The failure rate of this treatment modality is higher in cases where the duration of infection symptoms exceeds 4 weeks.
Schoifet and Morrey reported an overall failure rate of 77% for treatment of periprosthetic infections by irrigation and debridement. Treatment failed in all cases with symptoms lasting longer than 28 days.
Although some studies have concluded that the time between the onset of symptoms of infection and surgery (<4 weeks) is not a factor in outcome, some investigators have found that treatment success is improved if surgery is performed within a relatively short time after the onset of symptoms.
Brandt et al. reported that irrigation and debridement more than 2 days after the onset of symptoms increased the likelihood of treatment failure.
Marculescu et al. reported that the risk of treatment failure was twice as high for those with symptoms lasting longer than 8 days as for those who received timely treatment, while Hsieh et al. found that a shorter duration of preoperative symptoms (<5 days) was the only identifiable factor associated with treatment success when treating periprosthetic infections with Gram-negative bacteria with irrigation debridement.
Treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections is particularly difficult due to their septic nature and the limited antibiotic options available. Reports in the literature suggest an overall increasing trend in MRSA infection in joint replacement cases.
Bradbury et al. reported an 84% failure rate at least 2 years postoperative follow-up in 19 cases of acute periprosthetic MRSA infection who underwent open irrigation debridement and retained the prosthesis. These authors also reported that their review of 34 relevant publications identified 13 cases of TKA with a diagnosis of acute MRSA infection that had a 77% failure rate after treatment with open irrigation debridement and retention of the prosthesis.
One-stage revision prosthesis replacement One-stage revision prosthesis replacement involves removal of all prosthetic components and reinsertion of a new prosthesis in the same procedure. Despite the attractiveness of this treatment option, limited information is available based on small sample case studies.
The two studies with the largest sample sizes included 22 and 18 cases, respectively, and their success rates ranged from 89% to 91%. With the current increase in drug-resistant strains, only a small number of cases that meet specific criteria are appropriate candidates for this treatment option. Factors affecting treatment success include the absence of significant patient comorbidities, the addition of antibiotics sensitive to the causative organism to the bone cement, Gram-stain-positive causative bacterial infections, the absence of sinus tract formation, and a long duration (12 weeks) of intravenous antibiotic therapy.
Staged revision and replacement of the prosthesis is currently considered the gold standard for the treatment of chronic periprosthetic infections after THA (sic, TKA), including removal of the infected prosthesis and debridement of all necrotic tissue and foreign bodies such as bone cement, placement of a bone cement spacer with a high concentration of sensitive antibiotics in the joint space, followed by intravenous antibiotic therapy for specific pathogenic organisms.
Factors that influence the efficacy include the type and dose of antibiotic added to the cement spacer, the type of cement spacer (static or articular), the duration of intravenous antibiotic treatment, and the length of time between the phase I procedure, in which the original prosthesis is removed and debrided, and the phase II procedure, in which the prosthesis is reinserted.
Antibiotics: type and dose Studies have shown that the addition of antibiotics to bone cement spacer is an important factor in the treatment of infections, and Leone and Hanssen reported that the addition of antibiotics to bone cement increased treatment success from 58% to 74-92%.
However, there is still controversy as to which antibiotic to add to bone cement and at what dose is appropriate. In general, a high concentration of antibiotic spacer is defined as between 2 and 8 grams of antibiotic per packet of bone cement. Currently, the most readily available antibiotic powders with heat stability include vancomycin, gentamicin, and tobramycin.
However, it is important to note that different bone cements precipitate antibiotic properties differently. The higher the concentration of antibiotics, the greater the porosity and cavities in the bone cement will also be created. This will facilitate the precipitation of antibiotics thereby creating a higher concentration of antibiotics locally in the lesion than that produced by intravenous application.
Although the literature reports varying systemic toxic effects associated with the addition of antibiotics to bone cement, the body generally tolerates high local antibiotic concentrations in bone cement well and with only a small systemic risk.
Static vs. Articular Spacer Static antibiotic cemented spacers maintain the joint space well and minimize cement debris formation, but the corresponding joint cannot be mobilized between procedures. The use of static-type bone cement Spacer may result in significant bone loss, Spacer displacement, and necrosis of the knee extension mechanism, and these adverse effects should be avoided as much as possible during use.
During surgery, the cement needs to be placed during the dough phase so that it can be shaped to the local bone surface. This avoids many of the problems associated with preformed static spacers (Figure 3).
Figure 3 Orthopantomogram of the knee showing intraoperative fabrication of a static antibiotic cemented Spacer while the articulating Spacer maintains periarticular soft tissue flexibility between procedures and reduces bone loss. This type of cemented Spacer maintains knee mobility until reimplantation of the prosthesis, thereby improving patient mobility and facilitating intraoperative visualization during revision surgery.
However, the most important thing is to ensure wound healing, and if there is difficulty in wound healing then joint motion must first be limited.
Several types of articulating knee cement Spacers are available, including femoral and tibial lateral Spacer components that are molded articulating cement Spacers (Figure 4).
Figure 4 Orthopantomogram (A) and lateral (B) radiographs of the knee showing an articulating cemented Spacer Recently, researchers have proposed either re-implanting the removed infected prosthesis by sterilization or using a new, inexpensive femoral prosthesis component and an all-polyethylene tibial component with a highly concentrated antibiotic cement to create a freely movable articulating Spacer.
However, regardless of the type of Spacer used, a thorough intraoperative debridement of the femoral medullary tunnel and tibial side is routinely performed and the corresponding bone tunnel is filled with antibiotic bone cement. The literature shows that up to 1/3 of infected TKA cases have an infection in the medullary cavity tunnel.
There is insufficient evidence to support the advantage of articular Spacer over static Spacer. Emerson et al. compared 26 cases of static Spacer with 22 cases of articular Spacer and showed no significant difference in infection rates between the two groups at 36 months postoperatively. However, joint mobility was generally better in cases receiving an articulating Spacer at the final follow-up than in those receiving a static Spacer.
Freeman et al. conducted a comparative study of static Spacer versus articulating Spacer and found that the success rate of infection clearance was comparable between the two methods, but that cases treated with articulating Spacer had better recovery of limb function.
The duration of antibiotic therapy is uncertain as to the appropriate duration and dosage of intravenous antibiotic therapy prior to reimplantation of the prosthesis following resection and reconstruction of an infected TKA. In general, the typical treatment regimen is to start with 6 weeks of intravenous antibiotic therapy after surgery and to stop antibiotics for 2-6 weeks for clinical evaluation.
Prior to preparation for reimplantation of the prosthesis, the patient needs to be examined including clinical and serologic tests to confirm the continued presence of infection. Serologic markers such as ESR and CRP levels are useful tools to evaluate the effectiveness of treatment. Although these indicators may not fully return to normal levels before reimplantation, they can demonstrate whether the infection has improved.
In one study, Kusuma et al. found that the percentage of cases in which the infection proved to have completely disappeared at the time of reimplantation was 54% and 21% for ESR and CRP, respectively, which remained high. However, the authors of this paper were unable to determine reasonable levels to determine the infection prior to reimplantation of the prosthesis.
During the treatment phase prior to stage II prosthesis reimplantation, it may be more important to use the trend of ESR and CRP levels showing a gradual decrease as an indicator of infection status than absolute values.
It is uncertain whether leukocyte counts and sorting ratios can be used to guide treatment, and joint fluid examination may yield false-negative results.
In second-stage reimplantation, a determination of whether infection is still present needs to be made again and needs to be considered in conjunction with the preoperative examination. Frozen section histology can be used to determine if infection is still present, but sampling errors and the experience of the pathologist may lead to uncertainty in the results.
If evidence of infection is still found, the prosthesis should not be reimplanted. Relative contraindications include very poor or lost knee extension mechanism, insufficient bone mass, and poor soft tissue condition to effectively close the incision.
Treatment outcomes Table 4 lists the successful cases of staged revision surgery to replace the prosthesis for chronically infected TKA over the past 10 years. A number of studies have shown success rates of between 85% and 91% for clearing the infection.
Mortazavi et al. recently conducted a study of 117 cases of periprosthetic infection in TKA treated with staged revision in an attempt to identify factors that could predict failure of staged revision therapy. A minimum 2-year follow-up identified 33 cases (28%) that required reoperative management due to persistent infection.
They examined a total of 15 preoperative and 11 operative factors that could be associated with treatment failure. As a result, despite the high failure rate of the study, they could only identify culture-negative infections, methicillin-resistant bacterial infections, and the timing of surgery at the time of reimplantation as risk factors for failure. In contrast, ESR and CRP levels at the time of the reimplantation procedure were not predictors of failure.
Joint fusion may need to be considered in cases where there is no reconstructive approach to salvage joint function in cases of infected TKA.
Corresponding indications include young patients with monoarticular lesions, disruption of the knee extension mechanism, very poor soft tissue envelope, and highly virulent pathogenic infections that cannot be effectively controlled with antibiotics.
Relative contraindications to prosthetic reimplantation include coexisting ipsilateral hip and knee lesions, severe segmental bone defects, and contralateral lower extremity amputation.
The most commonly used techniques for knee fusion include external bracing, intramedullary pinning, and double plate fixation. A controlled study found similar fusion and reinfection rates obtained with both external brace and intramedullary fixation fusion techniques. Intramedullary fixation had a higher chance of obtaining fusion than external stent fixation, but also had a greater chance of infection. Overall, the study showed an overall complication rate of 40% in all cases.
The most common complications after joint fusion were fusion failure, recurrence of infection, fracture of the internal fixation, and displacement. Despite the relatively high complication rate, joint fusion remains a reasonable option for limb salvage when other methods of treatment have failed.
Amputation may need to be considered in cases where repeated revision surgeries have failed due to infection or when severe infection threatens the patient’s life, when segmental hinged prosthesis replacement has been used, when there is severe bone loss, or when there is intractable pain.
Since an above-knee amputation is required to completely clear the infection, most patients are unable to walk normally after surgery, making recovery of limb function poor. Adequate preoperative communication to the patient and his family is required.
In summary, the possibility of infection should be considered in every case of TKA with postoperative pain until it can be ruled out. Preoperative information including ESR, CRP levels, joint fluid analysis, complete medical history, and careful physical examination should be obtained. The timing of the onset of infection is a key factor in determining whether to retain or remove the prosthesis.
It is important in treatment to rely on a team effort that includes specialists in infectious diseases. And the staged revision and replacement of the prosthesis using high-dose antibiotic bone cement Spacer remains the gold standard for the treatment of chronic deep periprosthetic TKA infections.