Infected Total Knee Arthroplasty Research Articles

Interleukin-1β Polymorphisms Are Genetic Markers of Susceptibility to Periprosthetic Joint Infection in Total Hip and Knee Arthroplasty

Periprosthetic joint infections (PJIs) are serious complications of prosthetic surgery. The criteria for the diagnosis of PJI integrate clinical and laboratory findings in a complex and sometimes inconclusive workflow. Host immune factors hold potential as diagnostic biomarkers in bone and joint infections. We reported that the humoral pattern-recognition molecule long pentraxin 3 (PTX3) predicts PJI in total hip and knee arthroplasty (THA and TKA, respectively). If and how genetic variation in PTX3 and inflammatory genes that affect its expression (IL-1β, IL-6, IL-10, and IL-17A) contributes to the risk of PJI is unknown. We conducted a case–control study on a Caucasian historic cohort of THA and TKA patients who had prosthesis explant due to PJI (cases) or aseptic complications (controls). Saliva was collected from 93 subjects and used to extract DNA and genotype PTX3, IL-1β, IL-6, IL-10, and IL-17A single-nucleotide polymorphisms (SNPs). Moreover, the concentration of IL-1β, IL-10, and IL-6 was measured in synovial fluid and plasma. No association was found between PTX3 polymorphisms and PJI; however, the AGG haplotype, encompassing rs2853550, rs1143634, and rs1143627 in IL-1β, was linked to the infection (p = 0.017). Also, synovial levels of all inflammatory markers were higher in cases than in controls, and a correlation emerged between synovial concentration of PTX3 and that of IL-1β in cases only (Spearman r = 0.67, p = 0.004). We identified a relationship between rs2853550 and the synovial concentration of IL-1β and PTX3. Our findings suggest that IL-1β SNPs could be used for the early identification of THA and TKA patients with a high risk of infection.

COMPARING THE OUTCOMES OF DIFFERENT EXTERNAL FIXATION TYPES FOR KNEE ARTHRODESIS FOLLOWING INFECTED TOTAL KNEE ARTHROPLASTY: A SYSTEMATIC REVIEW

IntroductionKnee arthrodesis is a useful limb salvage technique to maintain function in patients with complex and infected total knee arthroplasties (TKA). There are a number of commonly used external fixators, but no consensus on which of these are optimal.The aim of this study was to synthesise the current literature to guide clinical decision making and improve patient outcomes. We systematically review the literature to compare outcomes of external fixators in arthrodesis following infected TKA.Materials & MethodsA systematic review of the literature of primary research articles investigating the use of external fixators for knee arthrodesis after an infected TKA was conducted. Relevant articles were identified with a search strategy on online databases (EMBASE and Medline) and reviewed by two independent reviewers.Clinical outcome measures were independently extracted by two reviewers which included union rate, infection eradication rate, complication rate, time to fusion, and time in frame.ResultsCircular frames were more likely to result in union compared to biplanar (OR 1.40 p=0.456) and monoplanar frames (OR 2.28 p=0.018). Infection recurrence was least likely in those treated by circular frames when compared to monoplanar (OR 0.12 p=0.005) and biplanar external fixators (0.41 P=0.331). Complication rates were highest in the circular fixator group, followed by the monoplanar fixator group and biplanar fixator group at 34%, 31% and 11% respectively.ConclusionsAnalysis of the available literature suggests higher union and infection eradication rates with circular frames over the other two fixation methods despite a higher complication rate. There is a paucity in the literature and therefore, no firm conclusions can be drawn. Further research investigating the variations and biomechanical properties between different external fixation methods for knee arthrodesis is necessary. Further clarity in reporting and pooled data would be useful for future analysis.

A new dressing system for accelerating wound recovery after primary total knee arthroplasty: a feasibility study.

Currently, postoperative wound infection and poor healing of total knee arthroplasty have been perplexing both doctors and patients. We hereby innovatively invented a new dressing system to reduce the incidence of postoperative wound complications. We enrolled 100 patients who received primary unilateral total knee arthroplasty and then applied the new dressing system. The data collected included the number of dressing changes, postoperative hospital stay, Visual Analogue Scale score (VAS), the Knee Society Score (KSS), the Knee Injury and Osteoarthritis Outcome Score (KOOS), ASEPSIS scores, The Stony Brook Scar Evaluation Scale (SBSES), wound complications, dressing cost, the frequency of shower and satisfaction. Subsequently, a statistical analysis of the data was performed. Our findings demonstrated the average number of postoperative dressing changes was 1.09 ± 0.38, and the average postoperative hospital stay was 3.72 ± 0.98 days. The average cost throughout a treatment cycle was 68.97 ± 12.54 US dollars. Collectively, the results of VAS, KSS, and KOOS revealed that the pain and function of patients were continuously improved. The results of the four indexes of the ASEPSIS score were 0, whereas the SBSES score was 3.58 ± 0.52 and 4.69 ± 0.46 at two weeks and one month after the operation, respectively. We observed no wound complications until one month after the operation. Remarkably, the satisfaction rate of the patients was 91.85 ± 4.99% one month after the operation. In this study, we invented a new dressing system for surgical wounds after total knee arthroplasty and further confirmed its clinical feasibility and safety. ChiCTR2000033814, Registered 13/ June/2020.

Acute Haematogenous Revision Total Knee Arthroplasty Infection by Streptococcus canis Treated by Debridement, Antibiotics, and Implant Retention: A Case Report

Acute Haematogenous Revision Total Knee Arthroplasty Infection by Streptococcus canis Treated by Debridement, Antibiotics, and Implant Retention: A Case Report

The Safety of Glycopeptide-Impregnated Calcium Sulphate Following Debridement, Antibiotics and Implant Retention (DAIR) for Infected Total Knee Replacement.

Background and objective The impact of prosthetic joint infection (PJI) stretches far beyond the physical nature of the disease. It can result in psychological and social consequences, with significant morbidity and mortality for patients. Calcium sulphate-based delivery agents are effective in the management of PJI, yet with associated risks of systemic adverse events. This study aims to evaluate the risk of systemic adverse events when using calcium-sulphate-based local antibiotic delivery agents in the management of PJIs. Methodology We identified 43 patients who underwent debridement, antibiotics and implant retention (DAIR) for infected total knee arthroplasty (TKA) between 2008 and 2014. Patients in the control groupunderwent conventional intravenous and then oral antibiotic administration, while those in the intervention groupunderwent additional local antibiotic therapy via a calcium sulphate alpha hemihydrate matrix. Case notes and laboratory results data were compiled to establish the safety and efficacy of local glycopeptide delivery. Results Serum vancomycin levels were within the safe therapeutic range for all patients in the intervention group with no difference in serum assays between treatment groups (intervention 7.7 mg/L; control 8.0 mg/L; P = 0.85). Renal function for the study cohort improved at every time point post-operatively when referenced against pre-operative renal function (P < 0.05). There was no difference in renal function between intervention and control groups on day 1, one week, six weeks or 12 weeks post-operatively (P = 0.78, 0.89, 0.20 and 0.50). Conclusions Local glycopeptide delivery via a calcium sulphate alpha hemihydrate matrix did not result in systemic adverse consequences specifically not raising the systemic level of glycopeptide, nor reducing renal function. Implications for future research Although demonstrates a safety profile and potential therapeutic benefit, the long-term efficacy of this approach needs to be established. Importantly, selection bias may contribute to masking clinically significant differences in post-operative outcomes.

Real-World Evidence of the Impact of a Novel Surgical Irrigant on Surgical Site Infections in Primary Total Knee Arthroplasty Performed at an Ambulatory Surgery Center.

Background: Total knee arthroplasty (TKA) is one of the most common inpatient and outpatient surgical procedures performed in the United States and is predicted to increase 401% by 2040. Surgical site infections (SSIs) at an incidence rate of approximately 2% are costly post-operative complications in TKA. Intra-operative surgical irrigants are used to decrease contaminating microbial bioburden within the surgical site to prevent SSI. The primary objective of this retrospective study was to evaluate the impact of a novel surgical irrigant called XPERIENCE® Advanced Surgical Irrigation (XP; Next Science, Jacksonville, FL) on SSI incidence in primary TKA performed at an ambulatory surgery center (ASC). Patients and Methods: Primary TKAs were performed at a free-standing ASC. The novel surgical irrigant was used intra-operatively to rinse away debris and micro-organisms from the surgical site. Retrospective data collation included SSI rates, complication rates, and re-admissions due to SSI within 90 days of index surgery. Results: Among the 524 primary TKA surgeries, one peri-prosthetic joint infection (PJI) was diagnosed within 90 days of index surgery and one superficial incisional SSI was diagnosed within 30 days of index surgery. The PJI was attributed to an exogenously acquired upper respiratory tract infection rather than due to the failure of intra-operative regimes. The 0.19% PJI incidence rate indicated significant efficacy of XP in decreasing PJI. An overall complication rate of 7.82% was noted with none of the complications associated with usage of the novel surgical irrigant. Conclusions: XPERIENCE is a promising intra-operative antimicrobial irrigant that can be easily incorporated into a broader infection prevention strategy.

Augmented Articulating Spacers in Infected Total Knee Arthroplasty: Surgical Technique.

Periprosthetic joint infections (PJIs) are a prominent subject of discussion in orthopedics and are frequently debated at conferences and congresses. In the context of PJIs affecting the knee, the decision between following a one-stage or two-stage treatment approach has historically been a pivotal consideration. The first option is limited by indications and potentially devastating complications in case of failure, whereas the second is widely accepted as the gold standard. Initially, the spacer was conceived solely to restore and maintain knee space after removal of the implant. An articulating spacer was introduced to mitigate patient limitations and improve knee function and quality of life. Two main types of articulating spacers are utilized in knee PJI treatment: the mold spacer and the metal-on-poly spacer. This text outlines a technique for metal-on-poly spacer implants. Based on our experience and the existing literature, this approach facilitates early full weight bearing and faster recovery of the knee's range of motion, ultimately improving the quality of life after surgery, thus allowing the spacer retention for an extended period, as suggested by the 1.5-stage revision.

Periprosthetic Hip and Knee Infection: Is an Ipsilateral Uninfected Total Joint Arthroplasty at Risk?

BackgroundPeriprosthetic joint infections (PJIs) of total hip arthroplasty (THA) or total knee arthroplasty (TKA) may occur in the setting of an uninfected ipsilateral prosthetic joint. However, the risk to that uninfected ipsilateral joint is unknown. We analyzed the survivorship free from PJI in at risk THAs and TKAs following treatment of an ipsilateral knee or hip PJI, respectively. MethodsUsing our institutional total joint registry, we identified 205 patients who underwent treatment for PJI (123 THAs and 83 TKAs) with an at-risk ipsilateral in situ knee or hip, respectively, between 2000 and 2019. In total, 54% of index PJIs were chronic and 46% were acute. The mean age was 70 years, 47% were female, and the mean body mass index was 32. Kaplan-Meier survivorship analyses were performed. Mean follow-up was 6 years. ResultsThe 5-year survivorship free of PJI in an at-risk THA after an ipsilateral TKA was treated for PJI was 97%. The 5-year survivorship free of PJI in an at-risk TKA when the ipsilateral THA was treated for PJI was 99%. Three PJIs occurred (2 THAs and 1 TKA), all over 1 year from the index ipsilateral PJI treatment. One hip PJI was an acute hematogenous infection that resulted from pneumonia. The other 2 new PJIs were caused by the same organism as the index PJI and were due to a failure of source control at the index joint. ConclusionsWhen diagnosed with PJI in a single joint, the risk of developing PJI in an ipsilateral prosthetic joint within 5 years was low (1 to 3% risk). In the rare event of an ipsilateral infection, all occurred greater than one year from the index PJI and 2 of 3 were with the same organism when source infection control failed. Level of EvidencePrognostic Level III.

Intramedullary Positive Tissue Culture Increases the Risk of Reinfection Following One-Stage Septic Revision Total Knee Arthroplasty

BackgroundIntraoperative acquisition of representative tissue samples is essential during revision arthroplasty of the infected total knee arthroplasty (TKA). While the number of intraoperative tissue samples needed to identify the organism is well described in the literature, there is still a paucity of evidence regarding the location of positive intraoperative samples and their correlation to postoperative outcomes. MethodsThere were forty-two patients who had septic failure following one-stage revision TKA for periprosthetic joint infection who were identified between January 2009 and December 2017. They were matched to a control group of patients who had successful one-stage revision TKA without septic failure. The location of positive intraoperative tissue samples was categorized as: 1) soft tissue; 2) interface between bone and prosthesis; and 3) intramedullary (IM). Chi-square, Student’s t-, and Wilcoxon Mann-Whitney U-tests were used as appropriate. Univariate and multivariate logistic regression analyses were performed to evaluate predictors of septic failure. ResultsWeight > 100 kilograms (P = .033), higher Charlson Comorbidity Index (P < .001), and positive IM cultures (P < .001) were associated with a higher risk of reinfection after one-stage revision TKA. A positive IM sample carried a nearly five-fold increase in odds of reinfection (odds ratio 4.86, 95% confidence interval 1.85 to 12.78, P = .001). ConclusionsA positive IM culture sample is significantly associated with septic failure after one-stage exchange for periprosthetic joint infection of the knee. Patients who had positive IM cultures may benefit from longer postoperative antibiotic therapy for the treatment of one-stage exchange arthroplasty to minimize the risk of reinfection.

Arthrodesis following persistent periprosthetic knee infection using femoral condyle allograft: a case report and review of literature

Periprosthetic joint infections (PJI) of the knee are difficult to treat and can require costly and prolonged hospital stays, weeks or months of antibiotic therapy, and multiple surgical procedures. Knee arthrodesis is considered a last resort for persistent knee joint infections and provides stability and pain relief by fusing the knee joint. The authors describe a case of a persistent and difficult to treat periprosthetic total knee arthroplasty (TKA) infection, subjected to multiple surgeries and revisions, where an arthrodesis was performed as a last resort. The arthrodesis was performed using a femoral-tibial endomedullary nail with interposed femoral condyle allograft. Complete graft integration and consolidation was achieved without complications. The patient performed well post-operatively and is currently ambulatory with walking aids and has no knee pain. The removal of well-fixed metaphyseal sleeves in TKA can be challenging and associated with complications such as damage to the surrounding bone and soft tissue during the removal process. Taking special care and not rushing this step can present an extremely meaningful difference in the final outcome. In cases with large bone defects, especially after sleeve removal, allograft usage can be extremely useful for managing dead space and limb-length discrepancies while promoting faster bone healing. When successful, as was the case described, arthrodesis using allografts can have beneficial outcomes with high patient satisfaction and deliver function to previously very unhealthy joints and limbs.

Intraosseous Regional Administration of Vancomycin Prophylaxis for Primary and Revision Total Knee Arthroplasty.

The advantages of prophylaxis with intraosseous regional administration (IORA) of vancomycin for periprosthetic joint infection (PJI) in primary and revision total knee arthroplasty (TKA) include the ability to deliver antibiotics directly to the surgical bed and avert systemic delivery; the ability to precisely time and quickly administer vancomycin to achieve the highest concentrations at the beginning and throughout the surgical procedure; and the ability to avert several common and potentially serious adverse effects of intravenous vancomycin. Indications for IORA of vancomycin prophylaxis include the following clinical scenarios: revision TKA; obesity; diabetes; beta-lactam allergy; known colonization with methicillin-resistant Staphylococcus aureus (MRSA); individuals coming from institutions with a high MRSA incidence; previous ligamentous surgical procedure or osteotomy; current or recent smokers; in the primary TKA setting if the individual is considered high-risk as defined by the criteria above; and during reimplantation following 2-stage exchange for PJI.

The Use of Preoperative CRP and ESR as Predictive Markers of Prosthetic Joint Infection in Primary Total Hip and Knee Arthroplasty

The Use of Preoperative CRP and ESR as Predictive Markers of Prosthetic Joint Infection in Primary Total Hip and Knee Arthroplasty

Comparison of outcomes between fungal and non-fungal periprosthetic joint infections in total knee arthroplasty.

Fungal periprosthetic joint infections (PJIs) are rare, but their diagnosis and treatment are highly challenging. The purpose of this study was to investigate the clinical outcomes of patients with fungal PJIs treated with two-stage exchange knee arthroplasty combined with prolonged antifungal therapy. We reviewed our institutional joint arthroplasty database and identified 41 patients diagnosed with fungal PJIs and treated with two-stage exchange arthroplasty after primary total knee arthroplasty (TKA) between January 2001 and December 2020, and compared them with those who had non-fungal PJIs during the same period. After propensity score matching based on age, sex, BMI, American Society of Anesthesiologists grade, and Charlson Comorbidity Index, 40 patients in each group were successfully matched. The surgical and antimicrobial treatment, patient demographic and clinical characteristics, recurrent infections, survival rates, and relevant risk factors that affected joint survivorship were analyzed. We defined treatment success as a well-functioning arthroplasty without any signs of a PJI, and without antimicrobial suppression, at a minimum follow-up of two years from the time of reimplantation. The fungal PJI group demonstrated a significantly worse treatment success rate at the final follow-up than the non-fungal PJI group (65.0% (26/40) vs 85.0% (34/40); p < 0.001). The mean prosthesis-free interval was longer in the fungal PJI group than in the non-fungal PJI group (6.7 weeks (SD 5.8) vs 4.1 weeks (SD 2.5); p = 0.020). The rate of survivorship free from reinfection was worse in the fungal PJI group (83.4% (95% confidence interval (CI) 64.1 to 92.9) at one year and 76.4% (95% CI 52.4 to 89.4) at two years) than in the non-fungal PJI group (97.4% (95% CI 82.7 to 99.6) at one year and 90.3% (95% CI 72.2 to 96.9) at two years), but the differences were not significant (p = 0.270). Cox proportional hazard regression analysis identified the duration of the prosthesis-free interval as a potential risk factor for failure (hazard ratio 1.128 (95% CI 1.003 to 1.268); p = 0.043). Fungal PJIs had a lower treatment success rate than non-fungal PJIs despite two-stage revision arthroplasty and appropriate antifungal treatment. Our findings highlight the need for further developments in treating fungal PJIs.

ORGANISMS RESPONSIBLE FOR TOTAL KNEE PROSTHETIC JOINT INFECTION: A SAUDITERTIARY CENTER 10-YEAR-EXPERIENCE

Background: Total Knee arthroplasty (TKA) is a standard procedure to treat end-stage knee osteoarthritis. As with any surgery, complications may arise, and one of the common complications reported from knee replacement procedures is infection. In this study, we aimed to retrospectively determine the prevalence of the infections pathogens following TKA and identify the most common microorganisms involved in infections in knee arthroplasty. Methods: Data were gathered from archived medical files using a retrospective descriptive study methodology. The current study included patients who underwent total knee arthroplasty and experienced infections between 2007 and 2017 at King Abdul-Aziz Medical City (KAMC), Jeddah, Saudi Arabia. Results: Out of 56 patients, almost half were hypertensive (57.1%) and diabetic (46.4%). 51.8% of patients had bilateral TKA. Among the patients, a third (41.8%)had pain the primary organism identified was Staphylococcus (44.65%), and 20% of cases involved co-infection with another organism. 16% of patients had methicillin-resistant Staphylococcus aureus. Infections with pseudomonas, brucellosis, and tuberculosis were also present in 17.9%, 3.6%, and 1.8% of the patients, respectively. Conclusion: Staphylococci were identified as the primary organism responsible for prostheticknee infection in KAMC patients. We recommend a focus on staphylococci in both prophylactic and empirical antibiotic treatments. Additional multicenter studies examining larger sample sizes are required to identify other factors influencingProsthetic Joint Infection (PJI), including obtaining information on the patients antimicrobial sensitivity profiles and geographic factors.

Early results of a novel modular knee arthrodesis implant after uncontrolled periprosthetic knee joint infection

AimThe aim of this study is to evaluate the functional outcomes and complications after non-fusion knee arthrodesis with a modular segmental intramedullary implant used for infected total knee arthroplasty revisions.MethodsA retrospective review of the patients who had been surgically treated with a modular intramedullary arthrodesis implant for recurrent infection after revision TKA between January 2016 and February 2020 were included. The indications for arthrodesis were failed infected TKA with massive bone loss, deficient extensor mechanism and poor soft tissue coverage that precluded joint reconstruction with revision TKA implants. Clinical outcomes were assesed with visual analogue scale for pain (pVAS), Oxford knee score (OKS) and 12-item short form survey (SF-12). Full-length radiographs were used to verify limb length discrepancies (LLD).ResultsFourteen patients (4 male and 10 female) patients with a mean age of 69.3 (range, 59 to 81) years at time of surgery were available for final follow-up at a mean of 28.8 months (range, 24–35 months). All clinical outcome scores improved at the final follow-up (pVAS, 8.5 to 2.6, p = .01; OKS, 12.6 to 33.8, p = .02; SF-12 physical, 22.9 to 32.1, p = .01 and SF-12 mental, 27.7 to 40.2, p = .01). The mean LLD was 1.0 cm (range, + 15 – 2.3 cm). Re-infection was detected in three patients (21.4%). Two patients were managed with suppressive antibiotic treatment and a third patient required repeat 2-stage revision procedure. In one patient, a periprosthetic femur fracture was observed and treated with plate osteosynthesis.ConclusionUncontrolled infection after total knee arthroplasty can be effectively treated with arthrodesis using a modular intramedullary nail and satisfactory functional results can be obtained.Level of evidenceLevel 4, Retrospective cohort study.

Clinical Outcomes and Complications of 2-Stage Septic Versus Aseptic Revision Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

Although several studies have compared the clinical outcomes of septic and aseptic revision total knee arthroplasty (TKA), their results have been controversial. Therefore, this study aimed to compare clinical outcomes and complications of septic and aseptic revision TKA through a systematic review and meta-analysis. The PubMed (MEDLINE) and Embase databases were searched for studies evaluating the clinical outcomes and complications of 2-stage septic revision and aseptic revision TKAs. A systematic review of clinical outcomes (Knee Society Knee and Function Scores and range of motion) and complications (reoperation, infection, and failure rates) was conducted. Thirteen studies were included in the systematic review. The mean MINORS (Methodological Index for NOn-Randomized Studies) score of the included studies was 20.5 (range, 18 to 22). The meta-analysis revealed higher reoperation (risk ratio [RR], 1.98; 95% confidence interval [CI], 1.50 to 2.62; p < 0.00001), infection (RR, 4.08; 95% CI, 2.94 to 5.64; p < 0.00001), and failure rates (RR, 2.88; 95% CI, 1.38 to 6.03; p = 0.005) in septic revision TKAs than in aseptic revision TKAs. Moreover, septic revision TKAs showed lower Knee Society Knee Scores compared with aseptic TKAs (mean difference [MD], -6.86; 95% CI, -11.80 to -1.92; p = 0.006). However, the Knee Society Function Score (MD, -1.84; 95% CI, -7.84 to 3.80; p = 0.52) and range of motion (MD, -6.96°; 95% CI, -16.23° to 2.31°; p = 0.14) were not significantly different between septic and aseptic revision TKAs. Despite the heterogeneity of prosthesis designs and surgical protocols used in septic and aseptic revision TKAs, the results of this systematic review suggest that 2-stage septic revision TKAs have poorer clinical outcomes and higher complication rates than aseptic revision TKAs do. Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Validation of the Incidence of Reported Periprosthetic Joint Infections in Total Hip and Knee Arthroplasty in the Dutch Arthroplasty Register

BackgroundArthroplasty registers underreport the incidence of periprosthetic joint infections (PJIs). We validated the incidence of reported PJIs in total hip arthroplasties (THAs) and total knee arthroplasties (TKAs) in the Dutch Arthroplasty Register (LROI) using data from the Dutch National Nosocomial Surveillance Network (PREZIES). MethodsAll primary THAs and TKAs from the LROI and all primary THAs and TKAs performed in consenting hospitals from PREZIES between 2012 and 2018 were matched on date of birth, date of surgery, sex, hospital, and type of procedure (THA n = 91,208; TKA n = 80,304). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for PJIs registered in the LROI, using PREZIES as a reference. ResultsThe incidence of registered PJIs in THAs was 1.2% in PREZIES and 0.5% in the LROI. For TKAs, this was 0.7 and 0.4%, respectively. The PJIs in THAs in the LROI had a sensitivity of 0.32 (confidence interval [CI]: 0.29 to 0.35), specificity of 1.00 (CI: 1.00 to 1.00), PPV of 0.74 (CI: 0.70 to 0.78), and NPV of 0.99 (CI: 0.99 to 0.99). In TKAs, the sensitivity, specificity, PPV, and NPV were 0.38 (CI: 0.34 to 0.42), 1.00 (CI: 1.00 to 1.00), 0.65 (CI: 0.59 to 0.70), and 1.00 (CI: 1.00 to 1.00), respectively. ConclusionsThe LROI captures approximately one-third of the PJIs as revision within one year for infection or resection arthroplasty. The capture rate of PJIs can be improved by including all reoperations without component exchange and nonsurgical treatments with antibiotics only.

Functional Outcomes of Knee Arthrodesis for Infected Total Knee Arthroplasty.

As the occurrence of total knee arthroplasties (TKAs) is forecasted to continue rising, so too will the frequency of prosthetic joint infections (PJIs) and revision TKAs. Multiple revisions can result in an unreconstructible knee. In such instances, the knee may be salvaged through arthrodesis. We evaluated whether height, BMI, and age impacted patient-reported outcome measures (PROMs) in patients who underwent knee arthrodesis after revision TKA due to PJI. We conducted a retrospective review of patients undergoing arthrodesis for an infected TKA at a dedicated orthopedic infection service from 2014 to 2022. Patient demographics and PROMs from 36-Item Short Form Survey (SF-36) and Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaires were collected. Correlation analysis was performed to determine if any association between height, BMI, and age was present with the various PROMsand sub-scores. Forty-four patients (19 males, 25 females) were included, with a mean follow-up of 48 months. Increases in height (>166 cm), BMI (>30), and age (>62 years) had a statistically significant negative impact on three SF-36 components: health changes (P = 0.016), physical functioning ability (P = 0.0096), and general health components (P = 0.0075). Our results suggest that a knee arthrodesis is an acceptable option in patients with a persistent knee PJI with good functional PROMs and ambulatory status. Patients with shorter height, lower BMI, and younger age showed overall better outcomes. Knee arthrodesis can be an alternative option for amputationin patients with an infected TKA and provide good functional outcomes in selected patients.

Role of the Gastrocnemius Musculocutaneous with a Propeller Style Skin Flap in Knee Region Reconstruction: Indications and Pitfalls.

Background  Soft tissue reconstruction around the knee area is still an open question, particularly in persistent infections and multiple reoperations scenario. Flap coverage should guarantee joint mobility and protection, even when foreign materials are implanted. The chimeric harvesting of the musculocutaneous gastrocnemius flap, based on the sural artery perforators, can extend its applicability in soft tissue reconstruction of the upper leg, overcoming the drawbacks of the alternative pedicled flaps. Methods  A multicenter retrospective study was conducted enrolling patients who underwent to a pedicled, chimeric gastrocnemius musculocutaneous-medial sural artery perforator (GM-MSAP) or lateral sural artery perforator (GM-LSAP) flap for knee coverage in total knee arthroplasty (TKA) recurrent infections and oncological or traumatic defects of the upper leg from 2018 to 2021. Outcomes evaluated were the successful soft tissue reconstruction and flap complications. Surgical timing, reconstruction planning, technique, and rehabilitation protocols were discussed. Results  Twenty-one patients were included in the study. Nineteen GM-MSAPs and 2 GM-LSAPs were performed (soft tissue reconstruction in infected TKA [12], in infected hardware [4], and in oncological patients [5]). Donor site was closed primarily in 9 cases, whereas a skin graft was required in 12. Flap wound dehiscence (1), distal flap necrosis (1), distal necrosis of the skin paddle (1), and donor site infection (1) were the encountered complications. Flap reraise associated to implant exchange or extensive debridement was successful without requiring any further flap surgery. Conclusion  The propeller-perforator GM-MSAP offers qualitative defect coverage and easiness of multiple flap reraise due to skin availability and its laxity.

Inferior Outcomes for Patients Transferred Between Surgical Stages for Knee Periprosthetic Joint Infection

BackgroundPeriprosthetic joint infection (PJI) in total knee arthroplasty may result in 2-stage revision surgery. There are limited data describing outcomes when the first stage is completed at an outside hospital and the patient is referred to a tertiary center. We hypothesized that patients have greater success when both surgeries occur at a single center. MethodsThere were 25 knee PJI patients who presented with an antibiotic spacer and had a minimum 2-year follow-up who were retrospectively identified at a single tertiary referral center from 2014 to 2021. A cohort matched for age, sex, body mass index, Elixhauser comorbidity measure, spacer type, infectious organism, and year of surgery was established with patients who had both stages completed at the investigating institution. Modified Delphi success criteria of no subsequent surgery or reinfection with any species were compared. ResultsThe transferred group demonstrated a treatment success of 40% compared to 84% in the continuous group (P < .01). The transferred group was more likely to have an additional procedure between stages (44 versus 8%, P < .01), with a higher number of surgeries after primary total knee arthroplasty (4.8 versus 3.0, P < .01), between stages (1.4 versus 0.2, P < .01), and after second stage (0.8 versus 0.2, P = .03). The transferred group had longer durations between stages (20.1 versus 7.0 weeks, P < .01). ConclusionPatients who have PJIs transferred between stages demonstrated higher treatment failure. Surgeons should consider transfer early with a goal of continuous management by a single institution.