Aseptic Failure Research Articles

Combined Use of External Iliac Lymph Node Count and Bone Scintigraphy for PJI Diagnosis: A Prospective Study

Background: The reactive enlargement of external iliac lymph nodes and increased blood flow in the infected region are commonly observed in lower limb infections. We aimed to differentiate between aseptic loosening and periprosthetic joint infection (PJI) after joint replacement surgery by quantifying the number of enlarged external iliac lymph nodes and using bone scintigraphy to monitor blood flow. Methods: We recruited 124 patients undergoing revision surgery for aseptic loosening or PJI. All the patients underwent preoperative dual-energy computed tomography (DECT) imaging for external iliac lymph nodes and bone scintigraphy. The diagnostic value was evaluated using ROC curve analysis. Results: The number of enlarged external iliac lymph nodes was significantly higher in the PJI group than in the aseptic failure group (4.0 versus. 1.0, p value < 0.001). The median affected/unaffected side ratio in the blood pool phase of ECT in the PJI group was 1.49, significantly higher than the aseptic failure group’s median ratio of 1.04 (p value < 0.001). The AUC for diagnosing PJI using the number of enlarged lymph nodes alone was 0.91, and when using the bone scintigraphy blood pool phase alone, the AUC was 0.89. When both metrics were combined, the AUC increased to 0.95, which was higher than the AUCs for the ESR (AUC = 0.83), CRP (AUC = 0.76), and synovial fluid PMN% (AUC = 0.62). Conclusions: Combining the enlargement of the lymph node count with the bone scintigraphy blood pool phase is a promising approach for diagnosing PJI.

Improving the microbiological diagnosis of fracture-related infection and prosthetic joint infection through culturing sonication fluid in Bactec blood culture bottles.

Sonication of surgically removed implants appears to optimize the microbiological diagnosis in orthopedic implant-associated infections (OIAI). However, reports of infection with negative cultures can still reach high rates. A study evaluating the inoculation of sonication fluid into blood culture bottles (SFBCB) in patients with fracture-related infection (FRI) and prosthetic joint infection (PJI) is necessary. This study compared the accuracy SFBCB over the conventional sonication fluid cultures (CSFC) and tissue culture (TC). Consecutive patients who underwent implant removal surgeries due to any reason had their implants sonicated according to standardized method. Definitions of PJI and FRI were based upon criteria by European Bone and Joint Infection Society (EBJIS) and Metsemakers, respectively. Between three to five intraoperative tissue samples were processed. The implant`s sonication fluid was seeded onto sheep blood agar, chocolate agar, thioglycolate broth and on tryptic soy broth for CSFC, while was also inoculated into blood culture bottles and incubated in the automated system during 5 days for SFBCB. Overall, 74 patients were analyzed, of which 57 with OIAI (48 FRI and 09 PJI) and 17 aseptic failures (03 arthroplasties and 14 osteosynthesis). Interestingly, SFBCB demonstrated significantly higher sensitivity compared to CSFC (96.5% [95% CI, 88-100] vs. 78.9% [95% CI, 66-89], p = 0.004), and to TC (96.5% [95% CI, 88-100], vs. 57.9% [95% CI, 44-71], p < 0.001), whereas there were no significant differences in specificity between the three methods. In comparison to CSFC and TC, SFBCB improved sensitivity for diagnosing OIAI without compromising specificity.

Association between type III collagen degradation and local tissue damage of a single joint

ObjectiveThe development of disease-modifying drugs is limited by OA's heterogeneity and the challenge of defining clinical endpoints. Serological biomarkers are considered potential surrogate endpoints, but their contribution from single joints to systemic levels in OA patients is unclear. In this exploratory study we longitudinally assessed systemic biomarker levels' response to tissue damage and healing before and after surgery in patients undergoing knee or hip joint replacement revision for aseptic failure. Patients with chronic pain associated with a prior hip or knee arthroplasty, but not receiving revision surgery were included as control. MethodThe serological biomarker of MMP mediated type III collagen degradation C3M, associated with synovial tissue degradation, was measured at baseline before revision surgery, after revision surgery and at a 6-month follow-up in 48 patients with aseptic loosening of a knee or hip prosthesis and in 18 patients with chronic pain from a hip or knee prosthesis. Longitudinal changes in biomarkers were modeled using linear mixed models. ResultsNo differences between the aseptic loosening and chronic pain groups were observed at baseline. Revision surgery in the aseptic loosening group led to a swift increase in C3M, which normalized within 2–3 months. No changes in biomarker level were observed in chronic pain patients over three months. ConclusionThese findings suggest that tissue damage in a single joint significantly impacts systemic biomarker levels and underscores the relevance of systemic biomarkers in assessing local tissue remodeling.

Role of Serum Biomarkers in Differentiating Periprosthetic Joint Infections from Aseptic Failures after Total Hip Arthroplasties.

Background/Objectives: Periprosthetic joint infection (PJI) is a disastrous complication after joint replacement procedures as the diagnosis remains a significant challenge. The objective of this study is to assess the accuracy and test the interdependency of the proposed compound serum biomarkers for the diagnosis of PJI after total hip arthroplasties (THA). Methods: From January 2019 to December 2023, 77 consecutive cases that underwent revision total hip arthroplasties (rTHA) were included in a single-retrospective, observational cohort study. A total of 32 arthroplasties were classified as having septic complications using the European Bone and Joint Infection Society (EBJIS) definition from 2021, while the other 45 cases were assigned as aseptic failures (AF). Results: In the univariate analysis between the two groups created, statistically significant differences (p < 0.005) were found for the following variables: time from primary arthroplasty to symptom onset (Time PA-SO), neutrophil count, Lymphocyte count, haematocrit level (HCT) and haemoglobin level (HGB), C-reactive protein (CRP), the neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), monocyte lymphocyte ratio (MLR), systemic inflammation index (SII), systemic inflammation response index (SIRI), and aggregate inflammation systemic index (AISI). The ROC curve analysis showed that the SII (sensitivity 90.6% and specificity 62.2%) and the NLR (sensitivity 84.4% and specificity 64.4%) are the most accurate biomarkers. The multivariate analysis confirmed that NLR > 2.63 (p = 0.006), PLR > 147 (p = 0.021), MLR > 0.31 (p = 0.028), SII > 605.31 (p = 0.002), SIRI > 83.34 (p = 0.024), and AISI > 834.86 (p = 0.011) are all closely related to PJI diagnosis independently. Conclusions: The proposed serum biomarkers can be correlated with PJI diagnosis with the reserve of relatively low specificities.

Stress-shielding in aseptic loosening on the 3D printed acetabular cup in hip arthroplasty: review article

The increasing number of prosthetic hip replacement surgeries and their growing indication have led to a growing interest in understanding the factors that influence their long-term success. Total hip arthroplasty (THA) failure is mainly due to aseptic loosening. More rarely septic mobilization may occur. In the first case, many variables influence the bone-implant relationship and periprosthetic bone remodeling. Stress-shielding is the most evident but not fully explained manifestation of the bone implant interaction. Recently, three-dimensional (3D) printed titanium orthopedic implants have offered new perspectives in the field of hip prosthetics, enabling the customization and production of acetabular cups with enhanced biocompatibility. This review aims to evaluate the efficacy and reliability of 3D printed acetabular cups from the perspective of aseptic failure particularly related to the stress-shielding. The most recent clinical and preclinical studies will be reviewed, exploring the benefits and challenges associated with the use of these emerging technologies. Key factors, such as biocompatibility, mechanical stability, osseointegration, and wear resistance.

SHORT-TERM OUTCOME OF A MODERN MONOBLOCK TITANIUM FLUTED TAPERED REVISION STEM FOR COMPLEX PRIMARY AND REVISION TOTAL HIP ARTHROPLASTY

For over a decade, modular titanium fluted tapered (TFT) stems have demonstrated excellent clinical success for femoral revision total hip arthroplasty (THA) surgery. The aim of this study was to report the short-term outcomes of a novel modern monoblock TFT stem used for revision and complex primary THA with a minimum of 2 years follow-up.We identified 126 patients who received a single monoblock TFT stem - 26 patients for complex THA (failed fracture fixation) and 100 patients for revision THA. The reasons for revision THA included 40 for previous prosthetic joint infection (PJI), 42 for aseptic loosening, 9 for trunnionosis, 9 for periprosthetic fractures. The Paprosky grading for femoral bone loss at the time of surgery and the measured subsidence of femoral stems at 3 months follow-up were determined. We evaluated the number and indications for re-operations.The mean time from surgery was 3.9 years (range 2.0 to 6.9 years). A paired t-test analysis showed significant improvement from pre-operative versus post-operative clinical outcome scores (p&lt;0.001) for HHS (38.76 +/- 15.24vs. 83.42 +/- 15.38), WOMAC (45.6 ± 19.0 vs. 69.9 ± 21.3) and SF-12 Physical component (31.7 ± 8.1 vs. 37.8 ± 11.3) and SF-12 Mental component (48.2 ± 12.2 vs. 51.6 ± 12.5). The Paprosky grading for femoral bone loss was Grade 1 (3.9%), Grade 2 (35.7%), Grade 3A (47.6%), Grade 3B (11.1%) and Grade 4 (1.6%) cases. There were 18 re-operations (14.7%) with 13 for PJI (7 treated with implant retention, 6 treated with a two-staged revision), 4 for instability and one for acetabular aseptic loosening. There were no aseptic failures of the stem.This novel modern monoblock TFT stem provided reliable femoral fixation and has increasingly supplanted the use of modular TFT stems for complex primary and revision surgery in our institution.

Prevalence, risk factors, microbiological results and clinical outcome in unexpected positive intraoperative cultures in unclear and presumed aseptic hip and knee revision arthroplasties – A ten-year retrospective analysis with a minimum follow up of 2 years

BackgroundThe aim of this study was to assess the prevalence, microbiological spectrum, risk factors, and clinical outcomes of unexpected-positive-intraoperative-cultures (UPIC) in presumed aseptic and unclear revision-total-hip-/knee-arthroplasties (rTHA and rTKA) compared to culture-negative (CN) revisions. MethodsThis study reviewed all International-consensus-meeting-2018 (ICM 2018) negative or inconclusive rTHA (n = 751) and rTKA (n = 679) performed at our institution from 2011 to 2020 with a minimum follow-up of two years. A Kaplan-Meier-analysis was performed to determine the septic and aseptic-free implant survival in cases with UPIC's and matched culture-negative cases. Patient demographics, risk factors, microbiological spectrum and clinical outcomes were evaluated. ResultsThere were significantly more UPIC cases in rTHA 196/751 (26.1 %) compared to rTKA 113/679 (16.6 %); (p < 0.001). UPICs in rTKA and rTHA have a lower septic and aseptic implant-free-survival compared to CN revisions. Patients with a history of nickel allergy have a higher risk of an UPIC in rTHA and rTKA (p < 0.001). Septic re-revisions after UPIC had a significantly (H: p = 0.004; K: p = 0.030) shorter time period to the primary/previous surgery (H: 84 (IQR:41–797); K: 115 (IQR:55–446)) compared to patients with aseptic re-revisions after UPIC (H:1248 (IQR:178-3534); K: 827 (IQR:361-1183)). ConclusionUPICs have a higher rate of septic and aseptic failure than CN outcomes. UPICs are twice as common in rTHA compared to rTKA. Preoperative PJI workup reduces the UPIC rate. Nickel allergy is a risk factor for UPIC. Early revisions with UPICs after primary THA or TKA have a higher risk of septic failure. The translational potential of this articleThis article provides new information on revision rates for UPIC and potential risk factors for UPIC and its treatment failure.

Impact of systemic lupus erythematosus (SLE) on outcomes following aseptic and septic revision total knee arthroplasty: an analysis of the 2005-2018 nationwide inpatient sample.

Systemic lupus erythematosus (SLE) can adversely affect surgical outcomes, and the impact on revision total knee arthroplasty (TKA) outcomes is unclear. This study aimed to explore the impact of SLE on in-patient outcomes of revision TKA. The Nationwide Inpatient Sample (NIS) database from 2005 to 2018 was searched for patients aged ≥ 18years old who received revision TKA. Patients with and without SLE were propensity score matched (PSM) at a 1:4 ratio. Associations between SLE and in-hospital outcomes were examined using regression analyses. The study included 133,054 patients, with 794 having SLE. After 1:4 PSM, data of 3,970 patients were analyzed (SLE, 794; non-SLE, 3,176). Multivariate-adjusted analyses revealed that SLE patients had a significantly higher risk of postoperative complications (adjusted odds ratio [aOR] = 1.23, 95% confidence interval [CI]: 1.05-1.44, p = 0.011), non-routine discharge (aOR = 1.22, 95% CI: 1.02-1.46, p = 0.028), major blood loss (aOR = 1.19), respiratory failure/mechanical ventilation (aOR = 1.79), acute kidney injury (AKI) (aOR = 1.47), and wound dehiscence (aOR = 2.09). SLE patients also had a longer length of hospital stay (aBeta = 0.31) and greater total hospital costs (aBeta = 6.35) compared to non-SLE patients. Among those with aseptic failure, SLE patients had a significantly higher risk of postoperative complications (aOR = 1.23) and non-routine discharge (aOR = 1.36). SLE is independently associated with worse in-hospital outcomes in patients undergoing revision TKA. This study highlights the importance of heightened vigilance and tailored perioperative management for patients undergoing major surgeries in the background of SLE. Key Points • SLE significantly increases the risk of non-routine discharge, major blood loss, respiratory failure, acute kidney injury, and wound dehiscence, in patients undergoing aseptic and septic revision TKA. • Patients with SLE experience longer hospital stays and higher hospital costs compared to those without SLE. • The study's findings highlight the necessity for healthcare providers to consider the presence of SLE as a critical factor in preoperative planning and postoperative care to improve outcomes in revision TKA patients.

Dual-Energy Computed Tomography Iodine Maps: Application in the Diagnosis of Periprosthetic Joint Infection in Total Hip Arthroplasty

BackgroundThe challenge of early and rapid diagnosis of periprosthetic joint infection (PJI) remains important. This study aimed to assess the efficacy of dual-energy computed tomography (DECT) iodine maps for diagnosing PJI in total hip arthroplasty. MethodsWe prospectively enrolled 68 patients who had postoperative joint pain after hip arthroplasty. All patients underwent preoperative DECT iodine imaging to quantify iodine concentration (IC) in periprosthetic tissues during arterial and venous phases. The diagnostic efficacy of DECT iodine maps was evaluated by constructing receiver operating characteristic curves according to the Musculoskeletal Infection Society criteria. ResultsCompared with erythrocyte sedimentation rate (area under the curve [AUC] = 0.837), polymorphonuclear cell percentage (AUC = 0.703), and C-reactive protein (AUC = 0.837), periprosthetic tissue venous-phase IC (AUC = 0.970) and arterial-phase IC (AUC = 0.964) exhibited outstanding discriminative capability between PJI and aseptic failure. The PJI cut-off point was venous IC = 1.225 mg/mL, with a sensitivity of 92.31% and specificity of 90.48%; for arterial IC = 1.065 mg/mL, the sensitivity was 96.15% and specificity was 90.70%. ConclusionsThis study demonstrates the great potential of DECT iodine maps for the diagnosis of PJI around hip arthroplasty, which helps to differentiate between periprosthetic infection and aseptic failure after hip arthroplasty.

Active myeloperoxidase: a promising biomarker to differentiate "acute" and "low-grade" peri-prosthetic joint infections from aseptic failures.

The accurate distinction between periprosthetic joint infections (PJI) and aseptic failures (AF) is of paramount importance due to differences in treatment. However, this could be challenging by using the current criteria. Various synovial fluid biomarkers are being assessed to improve the diagnostic accuracy. Myeloperoxidase (MPO), an enzyme contained in the granules of neutrophils, may be a promising biomarker for PJI. Synovial fluids of 99 patients (n = 65 PJI according to EBJIS criteria; n = 34 AF) were collected in two specialized orthopedic centers. PJI were divided into acute (n = 33) and low-grade (n = 32) according to previously published classification. An activity assay specific for active MPO was performed in each sample. Ability of MPO to correctly discriminate patients with PJI from AF was determined by ROC analysis. The best discriminating cut-off value was determined by calculating the J Youden index. For all analyses, a P value < 0.05 was considered statistically significant. Active MPO was higher in PJI than AF (P < 0.0001). The ROC analysis revealed a significant area under the curve (AUC: 0.86; 95% CI: 0.78-0.93, P < 0.0001). A cut-off value of 561.9 U/mL, with good sensitivity (0.69) and specificity (0.88), discriminated between AF and PJI (accuracy 75.76%, 95% CI: 66.11-83.81%, positive likelihood ratio 5.88, 95% CI: 2.31-14.98 and negative likelihood ratio 0.35, 95%CI: 0.24-0.51). No difference in MPO levels was found between acute and chronic low-grade PJI. The proposed assay appears to be a reliable and affordable tool for detecting the active MPO in synovial fluid, with promising characteristics of sensitivity and specificity in discriminating both acute and low-grade PJI from AF. Further studies are needed to confirm MPO diagnostic cut-off values and validate their use in the routine clinical practice.

Improved cure rate of periprosthetic joint infection through targeted antibiotic therapy based on integrated pathogen diagnosis strategy.

This study aimed to determine whether combined of pathogen detection strategies, including specimen acquisition, culture conditions, and molecular diagnostics, can improve treatment outcomes in patients with periprosthetic joint infections (PJI). This retrospective study included suspected PJI cases from three sequential stages at our institution: Stage A (July 2012 to June 2015), Stage B (July 2015 to June 2018), and Stage C (July 2018 to June 2021). Cases were categorized into PJI and aseptic failure (AF) groups based on European Bone and Joint Infection Society (EBJIS) criteria. Utilization of pathogen diagnostic strategies, pathogen detection rates, targeted antibiotic prescription rates, and treatment outcomes were analyzed and compared across the three stages. A total of 165 PJI cases and 38 AF cases were included in this study. With the progressive implementation of the three optimization approaches across stages A, B and C, pathogen detection rates exhibited a gradual increase (χ2=8.282, P=0.016). Similarly, utilization of targeted antibiotic therapy increased stepwise from 57.1% in Stage A, to 82.3% in Stage B, and to 84% in Stage C (χ2=9.515, P=0.009). The 2-year infection control rate exceeded 90% in both stages B and C, surpassing stage A (71.4%) (χ2=8.317, P=0.011). Combined application of all three optimized protocols yielded the highest sensitivity of 91.21% for pathogen detection, while retaining higher specificity of 92.11%. The utilization of combined pathogen diagnostic strategies in PJI can increase pathogen detection rates, improve targeted antibiotic prescription, reduce the occurrence of antibiotic complications, and achieve better treatment outcomes.

Synovial fluid NMR-based metabolomics in septic and aseptic revision total knee arthroplasty: Implications on diagnosis and treatment.

Periprosthetic joint infection (PJI) is one of the most challenging complications following total knee arthroplasty. Despite its importance, there is a paucity of reports in the literature regarding its pathogenesis. Recently, cellular metabolic reprogramming has been shown to play an important role in the progression and outcome of infectious diseases. Therefore, the aim of this study was to evaluate the metabolites composition of the synovial fluid from patients with PJI or aseptic failure of total knee arthroplasties. The synovial fluids from 21 patients scheduled for revision total knee arthroplasty (11 with the diagnosis of PJI and 10 with aseptic failures) were analyzed using 1D 1H NMR spectroscopy. Univariate and multivariate statistical analyzes were used to identify metabolites that were differentially abundant between those groups. A total of 28 metabolites were identified and five of them found to be differentially abundant between infected and non-infected synovial fluids. Lactate, acetate and 3-hydroxybutyrate were found to be in a higher concentration, and glucose and creatine were found reduced in the synovial fluid from PJI patients. Synovial fluid from patients with PJI exhibit a distinct metabolic profile, possibly reflecting metabolic adaptation that occurs in the infected periprosthetic microenvironment. Further research and studies are warranted to gain a broader insight into the metabolic pathways engaged by both pathogen and immune cells in the context of a PJI.

Metaphyseal Fixation Using Cones and Sleeves for Severe Proximal Tibial Bone Loss

BackgroundTibial bone defects are commonly encountered in revision total knee arthroplasty (rTKA) and can be managed with metaphyseal cones or sleeves. Few studies have directly compared tibial cones and sleeves in rTKA, and none have limited this comparison to the most severe tibial defects. The purpose of this study was to evaluate and compare the outcomes of metaphyseal cones and sleeves for tibial reconstruction in rTKA regarding implant fixation and clinical outcomes. MethodsA retrospective review was conducted on patients undergoing rTKA in which metaphyseal cones or sleeves were utilized for addressing metaphyseal bone loss (34 cones and 18 sleeves). Tibial bone loss was classified according to the Anderson Orthopaedic Research Institute bone defect classification, with types 2B and 3 being included. Patient-reported outcomes and postoperative complications were collected, and a radiographic evaluation of osseointegration or loosening was performed. ResultsThere were 52 knees included (34 cones, 18 sleeves), with a median follow-up of 41.0 months. All-cause implant survival was 100% at 2 years and 96% (95% confidence interval: 76 to 99%) at 4 years, with 98% of tibial components demonstrating osseointegration at the final follow-up. During follow-up, there were a total 11 revisions, of which 1 sleeve was revised secondary to implant loosening. Tibial sleeves had a higher risk of revision compared to tibial cones (P < .01), and sleeves fixed with a hybrid technique were more likely to need revision than cones fixed by the same method (P = .01). ConclusionsPorous metaphyseal tibial cones and tibial metaphyseal sleeves both performed well at a 41-month median follow-up with no difference in aseptic survivorship between the 2 constructs. Both demonstrate high rates of osseointegration, low rates of aseptic failure, and significant improvement in Knee Society Scores in patients with severe tibial defects in rTKA.

Minimum 2-Year Outcomes of a Modern Monoblock Titanium Fluted Tapered Revision Stem for Complex Primary and Revision Total Hip Arthroplasty

BackgroundModular titanium fluted tapered (TFT) stems have demonstrated excellent clinical success for femoral revision total hip arthroplasty (THA) surgery. This study reports the short-term outcomes of a novel modern monoblock TFT stem used for revision and complex primary THA with a minimum of 2 years of follow-up. MethodsWe identified 126 patients who received a single monoblock TFT stem: 26 patients for complex THA (failed fracture fixation) and 100 patients for revision THA. The reasons for revision THA included 40 for previous periprosthetic joint infection, 42 for aseptic loosening, 9 for trunnionosis, and 9 for periprosthetic fractures. The Paprosky grading for femoral bone loss at the time of surgery and the measured subsidence of femoral stems at 3-month follow-up were determined. We evaluated the number and indications for reoperations. ResultsThe mean time from surgery was 3.9 years (range, 2.0 to 6.9). A paired t-test analysis showed significant improvement from preoperative versus postoperative clinical outcome scores (P < .001) for Harris Hip Score (38.76 ± 15.24 versus 83.42 ± 15.38), Western Ontario and McMaster Universities Arthritis Index (45.6 ± 19.0 versus 69.9 ± 21.3), Veterans RAND 12 Item Health Survey Physical component (31.7 ± 8.1 versus 37.8 ± 11.3), and Veterans RAND 12 Item Health Survey Mental component (48.2 ± 12.2 versus 51.6 ± 12.5). The Paprosky grading for femoral bone loss was Grade 1 (3.9%), Grade 2 (35.7%), Grade 3A (47.6%), Grade 3B (11.1%), and Grade 4 (1.6%) cases. There were 18 reoperations (14.7%), with 13 for periprosthetic joint infection (7 treated with implant retention and 6 treated with a 2-stage revision), 4 for instability, and 1 for acetabular aseptic loosening. There were no aseptic failures of the stem. ConclusionsThis novel modern monoblock TFT stem provided reliable femoral fixation and has increasingly supplanted the use of modular TFT stems for complex primary and revision surgery in our institution.

Finding the Optimal Screening Test for Periprosthetic Joint Infection: A Prospective Study

BackgroundNo single test has demonstrated absolute accuracy in the diagnosis of periprosthetic joint infection (PJI). Serological markers are often used as screening tools to avoid unnecessary joint aspiration in cases with a low probability of infection. This study aimed to determine the utility of standard-of-care serological tests as a screening tool for PJI in patients undergoing revision arthroplasty. MethodsThis prospective study enrolled 502 patients undergoing revision hip or knee arthroplasty between May 2017 and August 2021. A PJI was defined using a modified definition of the 2018 International Consensus Meeting criteria. Plasma D-dimer, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and fibrinogen were measured preoperatively. There were 82 patients undergoing reimplantation who were excluded. Additionally, 8 patients who had an inconclusive International Consensus Meeting score were also excluded. Of the 412 included patients, 317 (76.9%) underwent revision for aseptic failure, and 95 (23.1%) had PJI. Receiver operating characteristic curves were used to assess the diagnostic utility of each serological test. A pairwise comparison with Bonferroni correction was performed to determine whether the differences in areas under the curve (AUCs) between the tests were significant. Additional analyses were performed to find the threshold for each test that offered 100% sensitivity, allowing it to be the optimal screening test. ResultsAll 4 serological markers, D-dimer (AUC 0.860, sensitivity 81.3%, specificity 81.7%), CRP (AUC 0.862, sensitivity 90.4%, specificity 70.0%), ESR (AUC 0.833, sensitivity 73.9%, specificity 85.2%), and fibrinogen (AUC 0.798, sensitivity 74.7%, specificity 75.4%), demonstrated comparable accuracy for the diagnosis of PJI (all P > .05). When maximizing sensitivity to 100%, D-dimer demonstrated the highest specificity (AUC 0.860, specificity 40.2%), outperforming ESR (AUC 0.833, specificity 3.3%), fibrinogen (AUC 0.798, specificity 2.3%), and CRP (AUC 0.862, specificity 0%). A plasma D-dimer level of ≥ 244 ng/mL was identified as the optimal cutoff for use as a screening test. ConclusionsAlthough plasma D-dimer demonstrated similar diagnostic accuracy as CRP, ESR, and fibrinogen, it outperformed all 3 aforementioned serological markers when used as a screening test for PJI. Level of EvidenceLevel II.

[Artículo traducido] Aparición temprana de líneas radiolúcidas alrededor de la artroplastia total de rodilla en pacientes con artritis reumatoide. ¿Cuál es su impacto en la tasa de fracaso aséptico y los resultados funcionales a los 13 años de seguimiento?

IntroductionAseptic total knee arthroplasty (TKA) failure has been associated with radiolucent lines. This study aimed to determine the impact of the early appearance of radiolucent lines (linear images of 1, 2, or > 2mm at the cement–bone interface) around the TKA on prosthetic survival and functional outcomes in rheumatoid arthritis (RA) patients during a 2–20 years follow-up. MethodsWe retrospectively analyzed a consecutive series of RA patients treated with TKA between 2000 and 2011. We comparatively analyzed patients with and without radiolucent lines around implants. Clinical outcomes were assessed with the knee society score (KSS) collected before surgery, at years 2, 5, and 10, and at the last postoperative follow-up. The knee society roentgenographic evaluation system was used to analyze the impact of radiolucent lines around the implants at 1, 2, 5, and more than ten years of follow-up. The reoperation and prosthetic survival rates were calculated at the end of the follow-up. ResultsThe study series included 72 TKAs with a median follow-up of 13.2 years (range: 4.0–21.0), of which 16 (22.2%) had radiolucent lines. We did not observe aseptic failure, and prosthetic survival at the end of the study was 94.4% (n=68). The KSS improved significantly (p<0.001) between preoperative values at 2, 5, and 10 years and the end of follow-up, with no differences between patients with and without radiolucent lines. ConclusionsOur study demonstrates that the early appearance of radiolucent lines around a TKA in RA patients does not significantly impact prosthetic survival or long-term functional outcomes at 13 years of follow-up.

Unreliability of Serum- or Plasma-based Assays of D-dimer or Fibrin (Fibrinogen) Degradation Product for Diagnosing Periprosthetic Joint Infection: A Prospective Parallel Study.

The ability of D-dimer to diagnose periprosthetic joint infection (PJI) before revision hip or knee arthroplasty is still controversial, and the differences in diagnostic ability between serum- or plasma-based assays of D-dimer and fibrin (fibrinogen) degradation product (FDP) are uncertain. The prospective parallel study was performed to determine the ability of D-dimer to diagnose PJI before revision hip or knee arthroplasty, and the differences in diagnostic ability between serum- or plasma-based assays of D-dimer and FDP. Patients undergoing knee or hip arthroplasty at our institution were prospectively enrolled into the following groups: those without inflammatory diseases who were undergoing primary arthroplasty ("Prim" group), those with inflammatory arthritis who were undergoing primary arthroplasty ("Prim/Inflam"), those undergoing revision arthroplasty because of aseptic failure ("Rev/Asept"), or those undergoing revision arthroplasty because of PJI ("Rev/PJI"). The ability of preoperative levels of D-dimer or FDP in serum or plasma to diagnose PJI in each group was assessed using areas under receiver operating characteristic curves (AUCs) and other diagnostic performance indicators. The diagnostic performance of these assays was compared with that of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). In the final analysis, Prim included 42 patients; Prim/Inflam, 40; Rev./Asept, 62; and Rev./PJI, 47. D-dimer assays led to AUCs of 0.635 in serum and 0.573 in plasma, compared to 0.593 and 0.607 for FDP. Even in combination with CRP or ESR, these assays failed to perform as well as the combination of CRP and ESR for diagnosing PJI. Levels of D-dimer or FDP in serum or plasma, whether used alone or together with CRP or ESR, are unreliable for diagnosing PJI before revision arthroplasty.

Long-term Outcomes of Revision Total Hip Arthroplasty Using a Modular Fluted Conical Femoral Stem

BackgroundThis study presents minimum 6-year follow-up data on the survival and satisfaction of an uncemented modular revision femoral system, following on from our previously published earlier results. MethodsWe retrospectively reviewed all revision hip arthroplasties performed at our institution between January 2005 and October 2012, using a single modular femoral revision system. Patient-reported outcomes were collected (satisfaction score and Oxford Hip Score). Preoperative and postoperative radiographs were reviewed for stem subsidence, and Kaplan–Meier analysis was performed for survival. A total of 115 femoral revisions were performed in 106 patients. ResultsAll-cause survival was 82% (95% confidence interval 74 to 91%) at 10.8 years, and 96% (95% confidence interval 90 to 100%) excluding septic failure. Of the 19 cases requiring reoperation, 16 were for infection, 2 for aseptic loosening, and 1 for mechanical failure. At final follow-up, 88.5% of patients were “satisfied” or “very satisfied”. ConclusionsThis study showed excellent clinical results of a commonly used revision hip stem with at least 10 years follow-up. Satisfaction rates were high, with few aseptic failures. Stem subsidence was more common in revisions for infection, but did not correlate with lower satisfaction scores.

Compressive Osseointegration Modular Prosthesis; Its Complications and Survival: A Systematic Review

Introduction: Minimal remaining bone is one condition that often complicates the limb salvage procedure. Compressive osseointegration is one of the latest modalities with a potential as a solution for this condition. While this modality is promising, the research on its effectivity and longevity on managing limb salvage in musculoskeletal tumor has not been widely studied, particularly in terms of complications and 5-year and 10-year implant survival rate. Materials and Methods: We comprehensively searched PubMed, Google Scholar, Cochrane Library, Science Direct, and Scopus for researches related to compressive osseointegration up to May 2021, which resulted in 89 articles. All publications were then reviewed by the authors based on PRISMA guidelines, which qualified 10 articles for systematic review. Results: Compressive osseointegration has been reported to have a high 5-year &amp; 10-year survival rate, up to 95% and 93% respectively, which are comparable to earlier models of implants. Earlier studies reported mechanical failure and prosthetic infection to be the most common complications to occur in compressive osseointegration, and occurred mostly before their second postoperative year, where mechanical failure is mostly caused by fall and strenuous activities on younger patients. Conclusion: Compressive osseointegration is a promising limb salvage endoprosthesis design. It offers capability of salvaging limb with minimal amount of bone remaining after resection. Complications that occurs from using this endoprosthesis are mostly aseptic failure, which occurs within two years postoperatively, resulting in 5-year and 10-year survival rate of 85% and 81% respectively. Keywords: compressive osseointegration, limb salvage, tumor, complication, survival

Periprosthetic Joint Infection Diagnosis: A Narrative Review.

Replacement of native joints aims to restore patients' quality of life by relieving pain and improving joint function. While periprosthetic joint infection (PJI) affects a small percentage of patients, with an estimated incidence of 1-9% following primary total joint replacement, this postoperative complication necessitates a lengthy hospitalisation, extended antibiotic treatment and further surgery. It is highlighted that establishing the correct diagnosis of periprosthetic infections is critical in order for clinicians to avoid unnecessary treatments in patients with aseptic failure. Of note, the PJI diagnosis could not purely rely upon clinical manifestations given the fact that heterogeneity in host factors (e.g., age and comorbidities), variability in infection period, difference in anatomical location of the involved joint and discrepancies in pathogenicity/virulence of the causative organisms may confound the clinical picture. Furthermore, intra-operative contamination is considered to be the main culprit that can result in early or delayed infection, with the hematogenous spread being the most prevalent mode. To elaborate, early and hematogenous infections often start suddenly, whereas chronic late infections are induced by less virulent bacteria and tend to manifest in a more quiescent manner. Last but not least, viruses and fungal microorganisms exert a role in PJI pathogenesis.