Mortality During Total Knee Periprosthetic Joint Infection

Background

Periprosthetic joint infections (PJIs) are fraught with multiple complications including poor patient-reported outcomes, disability, reinfection, disarticulation, and even death. We sought to perform a systematic review asking the question: (1) What is the mortality rate of a PJI of the knee undergoing 2-stage revision for infection? (2) Has this rate improved over time? (3) How does this compare to a normal cohort of individuals?

The Utility of Serum d-Dimer for the Diagnosis of Periprosthetic Joint Infection in Revision Total Hip and Knee Arthroplasty

BackgroundThere is scarce and contradicting evidence supporting the use of serum d-dimer for the diagnosis of periprosthetic joint infection in revision total hip (THA) and knee (TKA) arthroplasty. Therefore, the purpose of this study is to test the accuracy of serum d-dimer against the 2013 International Consensus Meeting (ICM) criteria.MethodsA retrospective review was performed on a consecutive series of 172 revision THA/TKA surgeries performed by 3 fellowship-trained surgeons at a single institution (August 2017 to May 2019) and that had d-dimer performed during their preoperative workup. Of this cohort, 111 (42 THAs/69 TKAs) cases had complete 2013 ICM criteria tests and were included in the final analysis. Septic and aseptic revisions were categorized per 2013 ICM criteria (“gold standard”) and compared against serum d-dimer using an established threshold (850 ng/mL). Sensitivity, specificity, likelihood ratios, and positive/negative predictive values were determined. Independent t-tests, Fisher’s exact tests, chi-squared tests, and receiver operating characteristic curve analysis were performed.ResultsThere was no statistically significant difference in baseline demographics between septic and aseptic cases per 2013 ICM criteria. When compared to ICM criteria, d-dimer demonstrated high sensitivity (95.9%) and negative predictive value (90.9%) but low specificity (32.3%), positive predictive value (52.8%), and overall, poor accuracy (61%) to diagnose periprosthetic joint infection. Positive likelihood ratio was 1.42 while negative likelihood ratio was 0.13. The area under the curve (AUC) was 0.742.ConclusionSerum d-dimer has poor accuracy to discriminate between septic and aseptic cases using a described threshold in the setting of revision THA and TKA.     

Risk of Prosthetic Joint Infection Increases Following Early Aseptic Revision Surgery of Total Hip and Knee Arthroplasty

BackgroundIt is important to identify risk factors for periprosthetic joint infection (PJI) following total joint arthroplasty in order to mitigate the substantial social and economic burden. The objective of this study is to evaluate early aseptic revision surgery as a potential risk factor for PJI following total hip (THA) and total knee arthroplasty (TKA).MethodsPatients who underwent primary THA or TKA with early aseptic revision were identified in 2 national insurance databases. Control groups of patients who did not undergo revision were identified and matched 10:1 to study patients. Rates of PJI at 1 and 2 years postoperatively following revision surgery were calculated and compared to controls using a logistic regression analysis.ResultsIn total, 328 Medicare and 222 Humana patients undergoing aseptic revision THA within 1 year of index THA were found to have significantly increased risk of PJI at 1 year (5.49% vs 0.91%, odds ratio [OR] 5.61, P < .001 for Medicare; 7.21% vs 0.68%, OR 11.34, P < .001 for Humana) and 2 years (5.79% vs 1.10%, OR 4.79, P < .001 for Medicare; 8.11% vs 1.04%, OR 9.05, P < .001 for Humana). Similarly for TKA, 190 Medicare and 226 Humana patients who underwent aseptic revision TKA within 1 year were found to have significantly higher rates of PJI at 1 year (6.48% vs 1.16%, OR 7.69, P < .001 for Medicare; 6.19% vs 1.28%, OR 4.89, P < .001 for Humana) and 2 years (8.42% vs 1.58%, OR 6.57, P < .001 for Medicare; 7.08% vs 1.50%, OR 4.50, P < .001 for Humana).ConclusionEarly aseptic revision surgery following THA and TKA is associated with significantly increased risks of subsequent PJI within 2 years.     

Dilute Betadine Lavage Reduces the Risk of Acute Postoperative Periprosthetic Joint Infection in Aseptic Revision Total Knee and Hip Arthroplasty: A Randomized Controlled Trial

BackgroundThe purpose of this randomized, controlled trial is to determine whether dilute betadine lavage compared to normal saline lavage reduces the rate of acute postoperative periprosthetic joint infection (PJI) in aseptic revision total knee (TKA) and hip arthroplasty (THA).MethodsA total of 478 patients undergoing aseptic revision TKA and THA were randomized to receive a 3-minute dilute betadine lavage (0.35%) or normal saline lavage before surgical wound closure. Fifteen patients were excluded following randomization (3.1%) and six were lost to follow-up (1.3%), leaving 457 patients available for study. Of them, 234 patients (153 knees, 81 hips) received normal saline lavage and 223 (144 knees, 79 hips) received dilute betadine lavage. The primary outcome was PJI within 90 days of surgery with a secondary assessment of 90-day wound complications. A priori power analysis determined that 285 patients per group were needed to detect a reduction in the rate of PJI from 5% to 1% with 80% power and alpha of 0.05.ResultsThere were eight infections in the saline group and 1 in the betadine group (3.4% vs 0.4%, P = .038). There was no difference in wound complications between groups (1.3% vs 0%, P = .248). There were no differences in any baseline demographics or type of revision procedure between groups, suggesting appropriate randomization.ConclusionDilute betadine lavage before surgical wound closure in aseptic revision TKA and THA appears to be a simple, safe, and effective measure to reduce the risk of acute postoperative PJI.Level of EvidenceLevel I.     

Reduced Infection Rate After Aseptic Revision Total Knee Arthroplasty With Extended Oral Antibiotic Protocol

BackgroundThe optimal postoperative antibiotic duration has not been determined for aseptic revision total knee arthroplasty (R-TKA) where the risk of periprosthetic joint infection (PJI) is 3%-7.5%. This study compared PJI rates in aseptic R-TKA performed with extended oral antibiotic prophylaxis (EOAP) to published rates.MethodsAseptic R-TKAs consecutively performed between 2013 and 2017 at a tertiary care referral center in the American Midwest were retrospectively reviewed. All patients were administered intravenous antibiotics while hospitalized and discharged on 7-day oral antibiotic prophylaxis. Infection rates and antibiotic-related complications were assessed.ResultsSixty-seven percent of the 176 analysis patients were female, with an average age of 64 years and body mass index of 35 kg/m². Instability and aseptic loosening comprised 86% of revision diagnoses. Overall, 87.5% of intraoperative cultures were negative, and the remainder were single positive cultures considered contaminants. PJI rates were 0% at 90 days, 1.8% (95% confidence interval 0.4%-5.3%) at 1 year, and 2.2% (95% confidence interval 0.6%-5.7%) at mean follow-up of approximately 3 years (range, 7-65 months).ConclusionEOAP after aseptic R-TKA resulted in a PJI rate equivalent to primary TKA, representing a 2- to-4-fold decrease compared with published aseptic R-TKA infection rates. Further study on the benefits and costs of EOAP after aseptic R-TKA is encouraged.     

High Mortality After Total Knee Arthroplasty Periprosthetic Joint Infection is Related to Preoperative Morbidity and the Disease Process but Not Treatment

BackgroundPeriprosthetic joint infection (PJI) mortality rate is approximately 20%. The etiology for high mortality remains unknown. The objective of this study was to determine whether mortality was associated with preoperative morbidity (frailty), sequalae of treatment, or the PJI disease process itself.MethodsA multicenter observational study was completed comparing 184 patients treated with septic revision total knee arthroplasty (TKA) to a control group of 38 patients treated with aseptic revision TKA. Primary outcomes included time and the cause of death. Secondary outcomes included preoperative comorbidities and Charlson Comorbidity Index (CCMI) measured preoperatively and at various postoperative timepoints.ResultsThe septic revision TKA cohort experienced earlier mortality compared to the aseptic cohort, with a higher mortality rate at 90 days, 1, 2, and 3 years after index revision surgery (P = .01). There was no significant difference for any single cause of death (P > .05 for each). The mean preoperative CCMI was higher (P = .005) in the septic revision TKA cohort. Both septic and aseptic cohorts experienced a significant increase in CCMI from the preoperative to 3 years postoperative (P < .0001 and P = .002) and time of death (P < .0001 both) timepoints. The septic revision TKA cohort had a higher CCMI 3 years postoperatively (P = .001) and at time of death (P = .046), but not one year postoperatively (P = .119).ConclusionCompared to mortality from aseptic revision surgery, septic revision TKA is associated with earlier mortality, but there is no single specific etiology. As quantified by changes in CCMI, PJI mortality was associated with both frailty and the PJI disease process, but not treatment.     

1.5-Stage Exchange Arthroplasty for Total Knee Arthroplasty Periprosthetic Joint Infections

BackgroundPeriprosthetic joint infection (PJI) in total knee arthroplasty (TKA) is a challenging problem. The purpose of this study was to outline a novel technique to treat TKA PJI. We define 1.5-stage exchange arthroplasty as placing an articulating spacer with the intent to last for a prolonged time.MethodsA retrospective review was performed from 2007 to 2019 to evaluate patients treated with 1.5-stage exchange arthroplasty for TKA PJI. Inclusion criteria included: articulating knee spacer(s) remaining in situ for 12 months and the patient deferring a second-stage reimplantation because the patient had acceptable function with the spacer (28 knees) or not being a surgical candidate (three knees). Thirty-one knees were included with a mean age of 63 years, mean BMI 34.4 kg/m², 12 were female, with a mean clinical follow-up of 2.7 years. Cobalt-chrome femoral and polyethylene tibial components were used. We evaluated progression to second-stage reimplantation, reinfection, and radiographic outcomes.ResultsAt a mean follow-up of 2.7 years, 25 initial spacers were in situ (81%). Five knees retained their spacer(s) for some time (mean 1.5 years) and then underwent a second-stage reimplantation; one of the five had progressive radiolucent lines but no evidence of component migration. Three knees (10%) had PJI reoccurrence. Four had progressive radiolucent lines, but there was no evidence of component migration in any knees.Conclusions1.5-stage exchange arthroplasty may be a reasonable method to treat TKA PJI. At a mean follow-up of 2.7 years, there was an acceptable rate of infection recurrence and implant durability.     

The Fate and Relevance of the Patella in Two-Stage Revision Total Knee Arthroplasty for Periprosthetic Joint Infection

BackgroundIt remains unclear whether reimplantation of a patellar component during a two-stage revision for periprosthetic total knee arthroplasty infection (PJI) affects patient reported outcome measures (PROMs) or implant survivorship. The purpose of this study was to evaluate whether patellar resurfacing during reimplantation confers a functional benefit or increases implant survivorship after two-stage treatment for PJI.MethodsTwo-stage revisions for knee PJI performed by three surgeons at a single tertiary care center were reviewed retrospectively. All original patellar components and cement were removed during resection and the patella was resurfaced whenever feasible during reimplantation. PROMs, implant survivorship, and radiographic measurements (patellar tilt and displacement) were compared between knees reimplanted with a patellar component versus those without a patellar component.ResultsA total of 103 patients met the inclusion criteria. Forty-three patients (41.7%) underwent reimplantation with, and 60 patients (58.3%) without a patellar component. At a mean follow-up of 33.5 months, there were no significant differences in patient demographics or PROMs between groups (P ≥ .156). No significant differences were found in the estimated Kaplan-Meier all-cause, aseptic, or septic survivorship between groups (P ≥ .342) at a maximum of 75 months follow-up. There was no significant difference in the change (pre-resection to post-reimplant) of patellar tilt (P = .504) or displacement (P = .097) between the groups.ConclusionPatellar resurfacing during knee reimplantation does not appear to meaningfully impact postoperative PROMs or survivorship. Given the risk of potential extensor mechanism complications with patellar resurfacing, surgeons may choose to leave the patella without an implant during total knee reimplantation and expect similar clinical outcomes.Level of EvidenceLevel III.     

Utility of Diagnostic Markers in Late Periprosthetic Joint Infection Workup for Total Knee Arthroplasty Patients Who Received Antibiotics 48 Hours Before Aspiration

BackgroundDiagnosing periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) remains challenging despite recent advancements in testing and evolving criteria over the last decade. Moreover, the effects of antibiotic use on diagnostic markers are not fully understood. Thus, this study sought to determine the influence of antibiotic use within 48 hours before knee aspiration on synovial and serum laboratory values for suspected late PJI.MethodsPatients who underwent a TKA and subsequent knee arthrocentesis for PJI workup at least 6 weeks after their index arthroplasty were reviewed across a single healthcare system from 2013 to 2020. Median synovial white blood cell (WBC) count, synovial polymorphonuclear (PMN) percentage, serum erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP), and serum WBC count were compared between immediate antibiotic and nonantibiotic PJI groups. Receiver operating characteristic (ROC) curves and Youden’s index were used to determine test performance and diagnostic cutoffs for the immediate antibiotics group.ResultsThe immediate antibiotics group had significantly more culture-negative PJIs than the no antibiotics group (38.1 versus 16.2%, P = .0124). Synovial WBC count demonstrated excellent discriminatory ability for late PJI in the immediate antibiotics group (area under curve, AUC = 0.97), followed by synovial PMN percentage (AUC = 0.88), serum CRP (AUC = 0.86), and serum ESR (AUC = 0.82).ConclusionAntibiotic use immediately preceding knee aspiration should not preclude the utility of synovial and serum lab values for the diagnosis of late PJI. Instead, these markers should be considered thoroughly during infection workup considering the high rate of culture-negative PJI in these patients.Level of EvidenceLevel III, retrospective comparative study.     

Two-Stage Exchange Arthroplasty for Periprosthetic Joint Infection Following Total Hip or Knee Arthroplasty Is Associated With High Attrition Rate and Mortality

BackgroundWe sought to determine the ultimate fate of patients undergoing resection arthroplasty as a first stage in the process of 2-stage exchange and evaluate risk factors for modes of failure.MethodsA retrospective case study was performed including all patients with minimum 2-year follow-up who underwent first-stage resection of a hip or knee periprosthetic joint infection from 2008 to 2015. Patient demographics, laboratory, and health status variables were collected. The primary outcome analyzed was defined as failure to achieve an infection-free 2-stage revision. Univariate pairwise comparison followed by multivariate regression analysis was used to determine risk factors for failure outcomes.ResultsEighty-nine patients underwent resection arthroplasty in a planned 2-stage exchange protocol (27 hips, 62 knees). Mean age was 64 years (range, 43-84), 56.2% were males, and mean follow-up was 56.3 months. Also, 68.5% (61/89) of patients underwent second-stage revision. Of the 61 patients who complete a 2-stage protocol, 14.8% (9/61) of patients failed with diagnosis of repeat or recurrent infection. Mortality rate was 23.6%. Multivariate analysis identified risk factors for failure to achieve an infection-free 2-stage revision as polymicrobial infection (P < .004; adjusted odds ratio [AOR], 7.8; 95% confidence interval [CI], 2.1-29.0), McPherson extremity grade 3 (P < .024; AOR, 4.1; 95% CI, 1.2-14.3), and history of prior resection (P < .013; AOR, 4.7; 95% CI, 1.4-16.4).ConclusionPatients undergoing resection arthroplasty for periprosthetic joint infection are at high risk of death (24%) and failure to complete the 2-stage protocol (32%). Those who complete the 2-stage protocol have a 15% rate of reinfection at 4.5-year follow-up.     

Revision Total Knee Arthroplasty for Periprosthetic Joint Infection Is Associated With Increased Postoperative Morbidity and Mortality Relative to Noninfectious Revisions

Background

Periprosthetic joint infection (PJI) after primary total knee arthroplasty (TKA) is a devastating complication. The short-term morbidity profile of revision TKA performed for PJI relative to non-PJI revisions is poorly characterized. The purpose of this study is to determine 30-day postoperative outcomes after revision TKA for PJI, relative to primary TKA and aseptic revision TKA.

Topical Vancomycin Powder and Dilute Povidone-Iodine Lavage Reduce the Rate of Early Periprosthetic Joint Infection After Primary Total Knee Arthroplasty

BackgroundVancomycin powder and dilute povidone-iodine lavage (VIP) was introduced to reduce the incidence of periprosthetic joint infection (PJI) in high-risk total knee arthroplasty (TKA) patients. We hypothesize that VIP can reduce the incidence of early PJI in all primary TKA patients, regardless of preoperative risk.MethodsAn infection database of primary TKAs performed before a VIP protocol was implemented (January 2012-December 2013), during a time when only high-risk TKAs received VIP (January 2014-December 2015), and when all TKAs received VIP (January 2016-September 2019) at an urban, university-affiliated, not-for-profit orthopedic hospital was retrospectively reviewed to identify patients with PJI. Criteria used for diagnosis of PJI were the National Healthcare Safety Network and Musculoskeletal Infection Society guidelines.ResultsVIP reduced early primary TKA PJI incidence in both the high-risk and all-risk cohorts compared with the pre-VIP cohort by 44.6% and 56.4%, respectively (1.01% vs 0.56% vs 0.44%, P = .0088). In addition, after introducing VIP to all-risk TKA patients, compared with high-risk TKA patients, the relative risk of PJI dropped an additional 21.4%, but this finding did not reach statistical significance (0.56% vs 0.44%, P = .4212). There were no demographic differences between the 3 VIP PJI cohorts.ConclusionVIP is associated with a reduced early PJI incidence after primary TKA, regardless of preoperative risk. With the literature supporting its safety and cost-effectiveness, VIP is a value-based intervention, but given the nature of this historical cohort study, a multicenter randomized controlled trial is underway to definitively confirm its efficacy.     

Revision Total Knee Arthroplasty for Failure of Primary Treatment of Periprosthetic Knee Fractures

Periprosthetic knee fractures and their complications are expected to increase as the numbers of knee arthroplasties continue to rise. We report our experience with revision knee arthroplasty for failure of primary fracture treatment. Five periprosthetic knee non-unions and 1 mal-union in 6 patients, with ages ranging from 65 to 83 years (average 74.6 years) were treated with revision total knee arthroplasty, and were followed up for 3 to 10 years (average 4.5 years). Union occurred in 8 to 18 weeks (average 12.5 weeks). All patients were ambulatory at the latest follow-up, with a range of motion averaging 84.2° (P = 0.03), and an Oxford Knee Score averaging 35 (P = 0.03). We conclude that union complications of periprosthetic knee fractures can be satisfactorily addressed with revision arthroplasty.     

Intraoperative Fracture During Aseptic Revision Total Knee Arthroplasty

Bone encountered during revision knee arthroplasty is compromised and predisposed to fracture. This study reports the rate, location, timing, treatment, and outcome of intraoperative fractures occurring during revision knee arthroplasty. Between 1997 and 2011, 2836 aseptic revisions were performed. Ninety-seven fractures were identified in 89 patients (3%). Fifty occurred in femora, 42 in tibiae, and 5 in patellae. Forty-six occurred during exposure, 21 during bony preparation, 17 during trialing, and 13 during final component placement. Treatment included fixation (n = 43), observation (n = 21), component build-up (n = 17), bone grafting (n = 6), and a combination (n = 3). Ninety-four percent of fractures united. Fifteen patients required a re-revision (17%), of which infection was the leading cause (n = 5).     

Primary Total Knee Arthroplasty in Infection Sequelae About the Native Knee

The aim of this study is to assess the results of primary total knee arthroplasty (TKA) after bone or joint sepsis about the native knee and to analyze the risk factors of periprosthetic infection. Sixty-two patients (62 knees), considered to have prior sepsis history to be resolved, underwent primary TKA and were followed during a mean of 6.1 years (range, 2–10.4 years). Of the 62 patients, periprosthetic infection occurred in 6 after primary TKA (9.7%). Five of 6 patients grew the same organism as prior infection. The number of prior surgeries undertaken for deep infection was found to be an independent risk factor of periprosthetic infection.     

Incidence and Predictors of Prosthetic Joint Infection Following Primary Total Knee Arthroplasty: A 15-Year Population-Based Cohort Study

BackgroundOne of the most devastating complications of total knee arthroplasty (TKA) is periprosthetic joint infection (PJI). Although many complications associated with TKA have decreased over time, the trends associated with PJI are less clear. Thus, the purpose of this study is to determine the incidence and risk factors for PJI after primary TKA.MethodsWe performed a population-based cohort study using linked administrative databases in Ontario, Canada. We used a Cox proportional hazards model to analyze the effect of surgical factors and patient factors on the risk of developing PJI.ResultsIn total, 129,613 patients aged 50+ received a primary TKA for osteoarthritis from 2002 to 2016 in Ontario, Canada. In total, 1.41% of patients underwent revision surgery for PJI. When accounting for censoring, the cumulative incidence for PJI was 0.51% (95% confidence interval 0.46-0.55) at 1 year, 1.12% (1.05-1.18) at 5 years, 1.49% (1.41-1.57) at 10 years, and 1.65% (1.55-1.75) at 15 years. The multivariable model revealed that male gender, younger age, type II diabetes, post-traumatic arthritis, patellar resurfacing, and discharge to convalescent care were associated with increased risk of PJI.ConclusionThe risk of PJI following TKA has decreased in small but steady increments over the past 15 years. Most PJIs are diagnosed within the first 2 years postoperatively, though a small group do continue to occur after 10 years. Overall, while the incidence of PJI has decreased slightly over the past 15 years, it remains among the most concerning complications of TKA and continued efforts aimed at further reducing its occurrence are needed.     

Gastrocnemius Muscle Flaps for Soft Tissue Coverage in Periprosthetic Knee Joint Infection

BackgroundSoft tissue deficiency in total knee arthroplasty infection is a potentially devastating complication. Gastrocnemius muscle flaps can be used to address this problem. We aim at reporting survival rates of these reconstructions and identify risk factors for failure.MethodsA retrospective evaluation of all flaps performed at a single center between 2006 and 2019 was performed. Clinical and microbiological results were assessed in 43 cases after a median follow-up period of 53 months (25%-75% interquartile range 18-79). Function was assessed using the Oxford Knee Score. We analyzed the infection-free survival and identified risk factors using survival comparison and (non-)parametric testing.ResultsInfection-free survival was 71% at 2 years and 63% at 5 years. The rate of subsequent amputation was 16% with a mortality rate of 26% during follow-up. Four patients did not undergo reimplantation and 11 patients received an arthrodesis implant. There were no failures of the flap itself. The Charlson Comorbidity index was the only relevant risk factor for reinfection. Coagulase-negative staphylococci were most common organisms identified. Postoperative function was limited with a mean Oxford Knee Score of 20.ConclusionGastrocnemius flap coverage is a valid option for soft tissue reconstruction in periprosthetic infections to retain a functioning limb despite a high complication rate and the risk of subsequent amputation.     

Greater Knee Soft Tissue Thickness Predisposes Patients to Subsequent Periprosthetic Joint Infection After Total Knee Arthroplasty

BackgroundAlthough obesity is a risk factor for periprosthetic joint infection (PJI) after total knee arthroplasty (TKA), the role of soft tissue thickness (STT) at the surgical site has not been well studied. This study examined if increased STT in the medial and anterior aspects of the knee are independent risk factors for PJI.MethodsA retrospective study was conducted on 206 patients who underwent 2-stage exchange arthroplasty for PJI from 2000 to 2015. They were matched 1:3 to a control group of primary, noninfected TKA patients with minimum 2 years infection-free survival by age, gender, age-adjusted Charlson Comorbidity Index, date of surgery, and body mass index (BMI). Two blinded orthopedic surgeons measured the medial STT from the medial aspect of the knee at the level of the joint line on an anteroposterior radiograph, and anterior STT 8 cm above the joint line on a lateral radiograph from the skin to the quadriceps tendon.ResultsIncreased STT was significantly associated with a higher risk for PJI. The mean anterior STT was 29.74 ± 13.76 mm in the PJI group and 24.88 ± 9.76 mm in the control group. The mean medial STT was 42.42 ± 14.66 mm for PJI and 37.27 ± 12.51 mm for control. Both STT measurements were significantly higher in PJI cases with BMI <30 kg/m² vs control patients with BMI <30 kg/m².ConclusionAnterior and medial knee STT was an independent risk factor for PJI after primary TKA and represents a simple radiographic method to assess postoperative infection risk. Excess adipose tissue around the surgical site can predispose patients to PJI after TKA regardless of BMI.     

Prior Septic Arthritis Within One Year of Knee Arthroplasty is Associated With a High Risk for Infection

BackgroundA prior history of a septic knee may predispose patients to a periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). We performed multivariate analyses of known risk factors that portend a periprosthetic infection for patients who have a history of septic arthritis (SA). The focus of the study was an assessment of the incidence of TKA PJIs at various time intervals after the onset of a septic knee (0 to 3 months, 3 to 6 months, 6 to 9 months, and 9 months to 1-year).MethodsWe queried a national database to identify patients who underwent a primary TKA between 2010 and 2021 (n = 1.9 million). Patients who had a prior septic knee ipsilateral to the primary TKA were characterized (n = 4,251) and were put into four specific cohorts based on the interval between the SA diagnosis and TKA: less than 3 months; 3 to 6 months; 6 to 9 months; and 9 to 12 months. A cohort of patients who did not have history of septic knee were used for comparison (n = 5,000). The incidence of PJIs from 90 days to 1 year was identified and compared using multivariate analyses.ResultsAll time cohorts were more likely to require revisions due to PJI, as compared to the comparison group. Significant differences were demonstrated among all time cohorts who had prior SA compared to patients who did not have a history of SA (odds ratio [OR] range, 90.0 to 113.0, P < .001).ConclusionThis study has shown an increased PJI risk in the first year after SA (P < .05). The surgeon should be aware of the increased PJI risk after SA within the first year after TKA.