Trial of Vancomycin and Cefazolin as Surgical Prophylaxis in Arthroplasty.

BACKGROUND: The addition of vancomycin to beta-lactam prophylaxis in arthroplasty may reduce surgical-site infections; however, the efficacy and safety are unclear. METHODS: In this multicenter, double-blind, superiority, placebo-controlled trial, we randomly assigned adult patients without known methicillin-resistant Staphylococcus aureus (MRSA) colonization who were undergoing arthroplasty to receive 1.5 g of vancomycin or normal saline placebo, in addition to cefazolin prophylaxis. The primary outcome was surgical-site infection within 90 days after surgery. RESULTS: A total of 4239 patients underwent randomization. Among 4113 patients in the modified intention-to-treat population (2233 undergoing knee arthroplasty, 1850 undergoing hip arthroplasty, and 30 undergoing shoulder arthroplasty), surgical-site infections occurred in 91 of 2044 patients (4.5%) in the vancomycin group and in 72 of 2069 patients (3.5%) in the placebo group (relative risk, 1.28; 95% confidence interval [CI], 0.94 to 1.73; P = 0.11). Among patients undergoing knee arthroplasty, surgical-site infections occurred in 63 of 1109 patients (5.7%) in the vancomyin group and in 42 of 1124 patients (3.7%) in the placebo group (relative risk, 1.52; 95% CI, 1.04 to 2.23). Among patients undergoing hip arthroplasty, surgical-site infections occurred in 28 of 920 patients (3.0%) in the vancomyin group and in 29 of 930 patients (3.1%) in the placebo group (relative risk, 0.98; 95% CI, 0.59 to 1.63). Adverse events occurred in 35 of 2010 patients (1.7%) in the vancomycin group and in 35 of 2030 patients (1.7%) in the placebo group, including hypersensitivity reactions in 24 of 2010 patients (1.2%) and 11 of 2030 patients (0.5%), respectively (relative risk, 2.20; 95% CI, 1.08 to 4.49), and acute kidney injury in 42 of 2010 patients (2.1%) and 74 of 2030 patients (3.6%), respectively (relative risk, 0.57; 95% CI, 0.39 to 0.83). CONCLUSIONS: The addition of vancomycin to cefazolin prophylaxis was not superior to placebo for the prevention of surgical-site infections in arthroplasty among patients without known MRSA colonization. (Funded by the Australian National Health and Medical Research Council; Australian New Zealand Clinical Trials Registry number, ACTRN12618000642280.).

Non-surgical correction of knee flexion deformity in persons with haemophilia: A staged multidisciplinary approach.

INTRODUCTION: Flexion deformity of the knee is a common complication following recurrent haemarthrosis in persons with haemophilia (PWH) on episodic factor replacement therapy, restricting independent mobility. There is limited literature on the comprehensive management of this condition. This report provides the outcome of a staged multidisciplinary approach for the correction of knee flexion deformity (KFD) even in limited resource settings. PATIENTS AND METHODS: The data of 49 consecutive PWH who were treated for KFD were analysed. The approach included graded physical therapy (PT), followed by serial casting and/or mobilisation under anaesthesia (MUA). MUA was done in carefully selected knees. Surgical correction was opted when non-surgical methods failed. RESULTS: Of the 49 patients (55 knees), with a median KFD of 40 degrees (range: 10-90), 26/55 (47%) were corrected by graded PT. With serial casting, 9/19 (47%) knees had their KFD corrected. MUA was done for 11 knees of which five achieved correction (45%). Surgical correction was required for only seven knees (12.7%). Following this approach, KFD improved from 40 degrees (range: 10-90) to 15 degrees (range: 0-40), with only minor loss of flexion from 105 (range: 60-155) to 90 degrees (range: 30-150). Out of 55 KFD, 46 (83.6%) KFD were corrected; non-surgical, 39 (70.9%) and surgery, seven (12.7%). The remaining patients (nine KFD; 16.4%) were able to achieve their functional goal despite not meeting the correction criteria. CONCLUSION: This study shows that in PWH, functionally significant KFD correction can be achieved in about 71%, through non-surgical methods, even without prophylactic factor replacement.

Accuracy and clinical role of digital templating for total knee arthroplasty performed on haemophilic knees.

INTRODUCTION: In total knee arthroplasty (TKA), choosing the correct implant size is important. There is lack of data on accuracy of templating on haemophilic knees. Our aim was to test the accuracy of 2D digital templating for TKA on haemophilic arthropathy (HA) of knee. MATERIALS AND METHODS: TKAs performed on HA between January 2011 and January 2022 were screened. Osteoarthritis (OA) group was created as control group by a one-to-one matching regarding type of implant used. Intra- and interobserver correlations were measured in HA, then correlation between templated and implanted sizes was investigated in four assessments (femur AP, femur lateral, tibia AP, tibia lateral), then compared with OA group. Fifty-eight knees in each group included. RESULTS: Regarding intraobserver correlation in HA, there was excellent correlation for femur AP [.93 (.73-.98)], femur lateral [.98 (.91-.99)], and tibia AP (1.0) templating. Regarding interobserver correlation in HA, excellent correlation was observed for femur lateral [.93 (.74-.98)] and tibia AP templating [.90 (.65-.97)]. Regarding correlation of templated and applied sizes in HA; tibia AP, tibia lateral and femur lateral templating showed good correlation [.81 (.70-.89), .86 (.77-.91), .79 (.67-.87) while femur AP templating showed moderate correlation [.67 (.50-.79)]. Comparing HA and OA, there was no difference in correlation levels regarding femur AP, femur lateral, tibia AP and tibia lateral templating (p = .056, p = .781, p = .761, p = .083, respectively). CONCLUSION: Although 2D digital templating shows comparable correlation in HA and OA, clinical applicability of templating on HA appears to be limited in its current state.

Movement-evoked Pain versus Pain at Rest in Postsurgical Clinical Trials and in Meta-analyses: An Updated Systematic Review.

BACKGROUND: Given the widespread recognition that postsurgical movement-evoked pain is generally more intense, and more functionally relevant, than pain at rest, the authors conducted an update to a previous 2011 review to re-evaluate the assessment of pain at rest and movement-evoked pain in more recent postsurgical analgesic clinical trials. METHODS: The authors searched MEDLINE and Embase for postsurgical pain randomized controlled trials and meta-analyses published between 2014 and 2023 in the setting of thoracotomy, knee arthroplasty, and hysterectomy using methods consistent with the original 2011 review. Included trials and meta-analyses were characterized according to whether they acknowledged the distinction between pain at rest and movement-evoked pain and whether they included pain at rest and/or movement-evoked pain as a pain outcome. For trials measuring movement-evoked pain, pain-evoking maneuvers used to assess movement-evoked pain were tabulated. RESULTS: Among the 944 included trials, 504 (53%) did not measure movement-evoked pain (vs. 61% in 2011), and 428 (45%) did not distinguish between pain at rest and movement-evoked pain when defining the pain outcome (vs. 52% in 2011). Among the 439 trials that measured movement-evoked pain, selection of pain-evoking maneuver was highly variable and, notably, was not even described in 139 (32%) trials (vs. 38% in 2011). Among the 186 included meta-analyses, 94 (51%) did not distinguish between pain at rest and movement-evoked pain (vs. 71% in 2011). CONCLUSIONS: This updated review demonstrates a persistent limited proportion of trials including movement-evoked pain as a pain outcome, a substantial proportion of trials failing to distinguish between pain at rest and movement-evoked pain, and a lack of consistency in the use of pain-evoking maneuvers for movement-evoked pain assessment. Future postsurgical trials need to (1) use common terminology surrounding pain at rest and movement-evoked pain, (2) assess movement-evoked pain in virtually every trial if not contraindicated, and (3) standardize movement-evoked pain assessment with common, procedure-specific pain-evoking maneuvers. More widespread knowledge translation and mobilization are required in order to disseminate this message to current and future investigators.

A Retrospective Study to Compare Patient Outcomes from Standard Total Knee Arthroplasty (TKA) versus Navigation-Guided Arthroplasty Using the Brainlab Software-Guided Surgical System at a Center in Hebei Province January 2021 to July 2023.

BACKGROUND This retrospective study aimed to compare patient outcomes from standard total knee arthroplasty (TKA) vs navigation-guided arthroplasty using the Brainlab software-guided surgical system at Cangzhou Hospital of Integrated TCM-WM, Hebei, Hebei Province, China from January 2021 to July 2023. MATERIAL AND METHODS A total of 239 patients who underwent total knee arthroplasty in Cangzhou Hospital of Integrated TCM-WM, Hebei from January 2021 to July 2023 were retrospectively analyzed. According to the inclusion criteria, 212 eligible patients were selected for analysis and divided into a Navigation Group (NG) (n=105) and a Traditional Group (TG) (n=107) according to surgical method used. Outcomes measured included duration of disease, operative time, intraoperative blood loss volume, postoperative length of hospital stay, and pain measured by the hospital for special surgery knee score (HSS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and forgotten joint score (FJS). RESULTS The comparison of perioperative results between the 2 groups showed that the incision length in the NG was significantly longer than that in the TG (P<0.001, 95% Cl 2.59-3.35). At 3 months after surgery, the HSS score of the NG was statistically higher than that of the TG (P=0.002, 95% Cl 3.42-4.46); the WOMAC score of the NG was lower than that of the TG (P<0.001, 95% Cl -4.41-2.87); and the FJS score of the NG was significantly higher than that of the TG (P=0.003, 95% Cl 2.39-3.67). CONCLUSIONS Compared with conventional TKA, use of the Brainlab navigation system is associated with a longer incision, more accurate implantation position of the prosthesis, faster recovery of knee joint function, and helps patients to "forget" about their knee prosthesis in the short term.

Advanced Imaging of Total Knee Arthroplasty.

The prevalence of total knee arthroplasty (TKA) is increasing with the aging population. Although long-term results are satisfactory, suspected postoperative complications often require imaging with the implant in place. Advancements in computed tomography (CT), such as tin prefiltration, metal artifact reduction algorithms, dual-energy CT with virtual monoenergetic imaging postprocessing, and the application of cone-beam CT and photon-counting detector CT, allow a better depiction of the tissues adjacent to the metal. For magnetic resonance imaging (MRI), high bandwidth (BW) optimization, the combination of view angle tilting and high BW, as well as multispectral imaging techniques with multiacquisition variable-resonance image combination or slice encoding metal artifact correction, have significantly improved imaging around metal implants, turning MRI into a useful clinical tool for patients with suspected TKA complications.

Ambulatory total hip and knee arthroplasty: a literature review and perioperative considerations.

PURPOSE: Total joint arthroplasty (TJA), particularly for the hip and knee, is one of the most commonly performed surgical procedures. The advancement/evolution of surgical and anesthesia techniques have allowed TJA to be performed on an ambulatory/same-day discharge basis. In this Continuing Professional Development module, we synthesize the perioperative evidence that may aid the development of successful ambulatory TJA pathways. SOURCE: We searched MEDLINE, Embase, CENTRAL, and the Cochrane Database of Systematic Reviews for ambulatory or fast-track TJA articles. In the absence of direct evidence for the ambulatory setting, we extrapolated the evidence from the in-patient TJA literature. PRINCIPAL FINDINGS: Patient selection encompassing patient, medical, and social factors is fundamental for successful same-day discharge of patients following TJA. Evidence for the type of intraoperative anesthesia favours neuraxial technique for achieving same day discharge criteria and reduced perioperative complications. Availability of short-acting local anesthetic for neuraxial anesthesia would affect the anesthetic choice. Nonetheless, modern general anesthesia with multimodal analgesia and antithrombotics in a well selected population can be considered. Regional analgesia forms an integral part of the multimodal analgesia regime to reduce opioid consumption and facilitate same-day hospital discharge, reducing hospital readmission. For ambulatory total knee arthroplasty, a combination of adductor canal block with local anesthetic periarticular infiltration provided is a suitable regional analgesic regimen. CONCLUSION: Anesthesia for TJA has evolved as such that same-day discharge will become the norm for selected patients. It is essential to establish pathways for early discharge to prevent adverse effects and readmission in this population. As more data are generated from an increased volume of ambulatory TJA, more robust evidence will emerge for the ideal anesthetic components to optimize outcomes.

RéSUMé: OBJECTIF: L'arthroplastie par prothèse totale (APT), en particulier de la hanche et du genou, constitue l'une des interventions chirurgicales les plus couramment pratiquées. L'avancement et l'évolution des techniques chirurgicales et d'anesthésie ont permis de réaliser une APT en ambulatoire/sur la base d'un congé le jour même. Dans ce module de développement professionnel continu, nous proposons une synthèse des données probantes périopératoires qui pourraient contribuer à l'élaboration de trajectoires réussies pour l'APT en ambulatoire. SOURCES: Nous avons réalisé des recherches dans MEDLINE, Embase, CENTRAL et dans la base de données Cochrane des revues systématiques à la recherche d'articles sur les APT ambulatoires ou accélérées. En l'absence de données probantes directes dans un contexte ambulatoire, nous avons extrapolé les données probantes à partir de la littérature sur les APT en milieu hospitalier. CONSTATATIONS PRINCIPALES: La sélection des patient·es englobant les facteurs patient·es, médicaux et sociaux est fondamentale pour un congé réussi le jour même après une APT. Les données probantes portant sur le type d'anesthésie peropératoire privilégient la technique neuraxiale pour respecter les critères de congé le jour même et réduire les complications périopératoires. La disponibilité d'un anesthésique local à courte durée d'action pour l'anesthésie neuraxiale affecterait le choix de l'anesthésique. Néanmoins, dans une population bien sélectionnée, l'anesthésie générale moderne avec analgésie multimodale et antithrombotiques peut être envisagée. L'analgésie régionale fait partie intégrante d'un régime d'analgésie multimodale visant à réduire la consommation d'opioïdes et à faciliter le congé de l'hôpital le jour même, ce qui réduit le nombre de réadmissions. En ce qui concerne l'arthroplastie totale du genou en ambulatoire, la combinaison d'un bloc du canal des adducteurs et d'une infiltration périarticulaire d'anesthésique local constitue un régime approprié d'analgésie régionale. CONCLUSION: L'anesthésie pour les APT a évolué de telle sorte que le congé le jour même deviendra la norme pour certain·es patient·es. Il est essentiel d'établir des trajectoires de congé précoce afin de prévenir les effets indésirables et la réadmission dans cette population. Au fur et à mesure que davantage de données seront générées à partir d'un volume accru d'APT en ambulatoire, des données probantes plus solides émergeront pour appuyer les composantes idéales de l'anesthésie pour optimiser les devenirs.

Comparison of the Kinematics and Laxity of Total Knee Arthroplasty Bearing Designs Stabilized With Specimen-Specific Virtual Ligaments on a Joint Motion Simulator.

A variety of total knee arthroplasty (TKA) designs offer increased congruency bearing options, primarily to compensate for a loss of posterior cruciate ligament (PCL) function. However, their efficacy in providing sufficient stability under different circumstances requires further investigation. The preclinical testing of prosthesis components on joint motion simulators is useful for quantifying how design changes affect joint stability. However, this type of testing may not be clinically relevant because surrounding ligaments are either ignored or greatly simplified. This study aimed to assess the kinematics and stability of TKA joints during various motions using condylar-stabilized (CS) bearings without a PCL versus cruciate-retaining (CR) bearings with an intact PCL. TKA prosthetic components were tested on a joint motion simulator while being stabilized with five different sets of specimen-specific virtual ligament envelopes. In comparison to CR knees, CS knees without a PCL exhibited a greater amount of posterior tibial displacement laxity, with a mean increase of 2.7±2.1 mm (p = 0.03). Additionally, significant differences were observed in the anterior-posterior kinematics of the knee joint during activities of daily living (ADL) between the two designs. These results were consistent with previous cadaveric investigations, which indicated that CS knees without a PCL are less resistant to posterior tibial displacement than CR knees with one. This study employing virtual ligaments confirms previous findings that the raised anterior lip of some CS bearings may not completely compensate for the absence of the PCL; however, as both studies used reduced joint contact forces, the contributions of this design feature may be attenuated.

Simultaneous Evaluation of Tibiofemoral and Patellofemoral Mechanics in Total Knee Arthroplasty: A Combined Experimental and Computational Approach.

Contemporary total knee arthroplasty (TKA) has not fully restored natural patellofemoral (P-F) mechanics across the patient population. Previous experimental simulations have been limited in their ability to create dynamic, unconstrained, muscle-driven P-F articulation while simultaneously controlling tibiofemoral (T-F) contact mechanics. The purpose of this study was to develop a novel experimental simulation and validate a corresponding finite element model to evaluate T-F and P-F mechanics. A commercially available wear simulator was retrofitted with custom fixturing to evaluate whole-knee TKA mechanics with varying patella heights during a simulated deep knee bend. A corresponding dynamic finite element model was developed to validate kinematic and kinetic predictions against experimental measurements. Patella alta reduced P-F reaction forces in early and midflexion, corresponding with an increase in T-F forces that indicated an increase in extensor mechanism efficiency. Due to reduced wrapping of the extensor mechanism in deeper flexion for the alta condition, peak P-F forces in flexion increased from 101% to 135% of the applied quadriceps load for the baja and alta conditions, respectively. Strong agreement was observed between the experiment and model predictions with root-mean-square errors (RMSE) for P-F kinematics ranging from 0.8 deg to 3.3 deg and 0.7 mm to 1.4 mm. RMSE for P-F forces ranged from 7.4 N to 53.6 N. By simultaneously controlling dynamic, physiological loading of the T-F and P-F joint, this novel experimental simulation and validated model will be a valuable tool for investigation of future TKA designs and surgical techniques.

Robotic-assisted TKA is Not Associated With Decreased Odds of Early Revision: An Analysis of the American Joint Replacement Registry.

BACKGROUND: Robotic-assisted TKA continues to see wider clinical use, despite limited knowledge of its impact on patient satisfaction and implant survival. Most studies to date have presented small cohorts and came from single-surgeon or single-center experiences. Therefore, a population-level comparison of revision rates between robotic-assisted and conventional TKA in the registry setting may help arthroplasty surgeons better define whether robotic assistance provides a meaningful advantage compared with the conventional technique. QUESTIONS/PURPOSES: (1) After controlling for confounding variables, such as surgeon, location of surgery, and patient comorbidity profile, were robotic-assisted TKAs less likely than conventional TKAs to result in revision for any reason at 2 years? (2) After again controlling for confounding variables, were robotic-assisted TKAs less likely to result in any specific reasons for revision than the conventional technique at 2 years? METHODS: The American Joint Replacement Registry was used to identify patients 65 years or older who underwent TKA between January 2017 and March 2020 with a minimum of 2 years of follow-up. Patients were limited to age 65 yeas or older to link TKAs to Medicare claims data. Two retrospective cohorts were created: robotic-assisted TKA and conventional TKA. Patient demographic variables included in the analysis were age, gender, BMI, and race. Additional characteristics included the Charlson comorbidity index, anesthesia type, year of the index procedure, and length of stay. A total of 10% (14,216 of 142,550) of TKAs performed during this study period used robotics. Patients with robotic-assisted TKA and those with conventional TKA were similar regarding age (73 ± 6 years versus 73 ± 6 years; p = 0.31) and gender (62% [8736 of 14,126] versus 62% [79,399 of 128,334] women; p = 0.34). A multivariable, mixed-effects logistic regression model was created to analyze the odds of all-cause revision as a factor of robot use, and a logistic regression model was created to investigate specific revision diagnoses. RESULTS: After controlling for potentially confounding variables, such as surgeon, location of surgery, and Charlson comorbidity index, we found no difference between the robotic-assisted and conventional TKAs in terms of the odds of revision at 2 years (OR of robotic-assisted versus conventional TKA 1.0 [95% CI 0.8 to 1.3]; p = 0.92). The reasons for revision of robotic-assisted TKA did not differ from those of conventional TKA, except for an increased odds of instability (OR 1.6 [95% CI 1.0 to 2.4]; p = 0.04) and pain (OR 2.1 [95% CI 1.4 to 3.0]; p < 0.001) in the robotic-assisted cohort. CONCLUSION: In light of these findings, surgeons should not assume that robotic assistance in TKA will lead to improved early implant survival. Our findings do not support an improvement over conventional TKA with robotic assistance with regards to common causes of early revisions such malalignment, malposition, stiffness, pain, and instability, and in some cases, suggest there is a benefit to conventional TKA. Differences in the mid-term and long-term revision risk with conventional versus robotic-assisted TKA remain unknown. Appropriate informed consent around the use of robotic assistance should not imply decreased early revision risk. LEVEL OF EVIDENCE: Level III, therapeutic study.

Allograft or Synthetic Mesh Extensor Mechanism Reconstruction After TKA Carries a High Risk of Infection, Revision, and Extensor Lag.

BACKGROUND: Extensor mechanism disruption is a devastating complication after TKA. Extensor mechanism reconstruction can be performed using an allograft or synthetic mesh. Recent studies have disagreed about the durability of these reconstructions. Evaluating a larger series of reconstructions that use current popular techniques and principles provides information to guide patient and surgeon expectations while bringing to light the potential fate of patients who experience an infection postoperatively. QUESTIONS/PURPOSES: (1) What was the 5-year survival free of repeat revision surgery or persistent extensor lag of more than 30° after allograft or synthetic mesh reconstruction of extensor mechanism disruptions after TKA, and did this differ between techniques? (2) What was the 5-year survival free of infection after allograft or mesh reconstruction, and what proportion of those patients experienced a secondary severe complication (arthrodesis or amputation)? METHODS: Between April 2008 and December 2020, 123 patients underwent extensor mechanism reconstruction after TKA at one center. Of those, 37% (45) were lost to follow-up before 2 years, had not been seen in the past 5 years, did not reach a study endpoint (repeat revision or extensor lag > 30°) before that time, or underwent primary repair and thus could not be analyzed, leaving 63% (78) for analysis here. During the study period, we considered extensor mechanism surgery when acute or chronic disruption of the patellar or quadriceps tendon was present or there was a fracture of the patella resulting in extensor lag. The decision to use either mesh or an allograft largely depended on surgeon experience and familiarity with either technique. We collected patient demographics, operative details (location of disruption and presence of a hinged prosthesis), subsequent periprosthetic joint infection (PJI), and postoperative SF-12 and Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, scores. We used Kaplan-Meier survivorship analysis, with endpoints of extensor lag more than 30° or revision of the reconstruction and PJI. The mean follow-up duration was 5.3 ± 3.2 years. RESULTS: Survivorship free from revision or recurrent extensor lag was 54% (95% CI 44% to 66%) at 5 years. There was no difference between those undergoing reconstruction with allografts and those with mesh in terms of survivorship free from those endpoints at that timepoint (52% [95% CI 40% to 68%] versus 57% [95 CI% 41 to 78%]; p = 0.99). Survivorship free from PJI was 81% (95% CI 73% to 90%) at 2 years. There was no difference between those with allografts and those with mesh in terms of survivorship free from PJI at that timepoint (79% [95% CI 69% to 92%] versus 83% [95% CI 71% to 98%]; p = 0.75). Of the 17 patients who experienced PJI, four ultimately underwent arthrodesis and three more underwent transfemoral amputation. CONCLUSION: Allograft and synthetic mesh reconstructions commonly left patients with persistent limb dysfunction, while several patients had PJI and some underwent salvage procedures. Although improvements have been made with regard to treating extensor mechanism disruptions, patients and surgeons should be well aware of the potential adverse outcomes when determining management and use these findings to conduct risk-benefit analyses. There is a need for future studies to identify protocols that improve the durability of reconstructions and to determine whether interventions such as prolonged prophylactic antibiotic therapy have a role in minimizing the risk of PJI. LEVEL OF EVIDENCE: Level III, therapeutic study.

Neutrophil Extracellular Trap-related Biomarkers Are Increased in the Synovial Fluid of Patients With Periprosthetic Joint Infections.

BACKGROUND: The diagnosis of periprosthetic joint infection (PJI) is a major challenge in clinical practice. The role of neutrophils in fighting infection has been increasingly understood, and one mechanism of action of these cells is neutrophil extracellular traps. However, little is known about this process in PJI. QUESTIONS/PURPOSES: (1) Are the biomarkers of neutrophil extracellular trap formation (citrullinated histone H3 [H3Cit], cell-free DNA [cf-DNA], and myeloperoxidase [MPO]) increased in the synovial fluid of patients with PJI? (2) What is the diagnostic accuracy of biomarkers of neutrophil extracellular trap formation for PJI? METHODS: Between May 2020 and March 2021, 43 patients who underwent revision THA or TKA were enrolled in this study. Eleven patients were excluded and 32 patients were categorized into the PJI group (n = 16) or non-PJI group (n = 16) according to the 2018 Second International Consensus Meeting on Musculoskeletal Infection criteria. There were 15 men and 17 women in this study, with a median (range) age of 70 years (60 to 80 years). Twenty-seven patients had TKA and five had THA. We measured cf-DNA, MPO, and H3Cit in synovial fluid. The sensitivity, specificity, and receiver operating characteristic curve were calculated for each biomarker using the Musculoskeletal Infection Society criteria as the gold standard for diagnosis and considering a clinical surveillance of 2 years for patients in the non-PJI group. RESULTS: Patients with PJI had higher levels of synovial fluid cf-DNA (median [range] 130 ng/µL [18 to 179] versus 2 ng/µL [0 to 6]; p < 0.001), MPO (1436 ng/µL [55 to 3996] versus 0 ng/µL [0 to 393]; p < 0.001), and H3Cit (2115 ng/µL [5 to 2885] versus 3 ng/µL [0 to 87]; p < 0.001) than those in the non-PJI group. In receiver operating characteristic curve analyses, we observed near-perfect performance for all biomarkers evaluated, with an area under the curve of 1 (95% CI 0.9 to 1), 0.98 (95% CI 0.9 to 1), and 0.94 (95% CI 0.8 to 0.99) for cf-DNA, MPO, and H3Cit, respectively. The sensitivity for detecting PJI using synovial fluid was 100% for cf-DNA, 94% for MPO, and 88% for H3Cit. The specificity was 100% for cf-DNA and MPO, and 88% for H3Cit. CONCLUSION: Our results show that neutrophils in the periprosthetic microenvironment release neutrophil extracellular traps as part of the bactericidal arsenal to fight infection. These results allow a better understanding of the cellular and molecular processes that occur in this microenvironment, enabling the design of more assertive strategies for identifying new biomarkers and improving the available ones. Novel studies are needed to define whether and how neutrophil extracellular trap-related biomarkers can be useful for diagnosing PJI. LEVEL OF EVIDENCE: Level II, diagnostic study.

Exploring patient perspectives on EQ-5D-5L data visualization within an individualized decision aid for total knee arthroplasty (TKA) in Alberta, Canada.

BACKGROUND: Decision aids can help patients set realistic expectations. In this study, we explored alternative presentations to visualise patient-reported outcomes (EQ-5D-5L) data within an online, individualized patient decision aid for total knee arthroplasty (TKA) that, in part, generates individualized comparisons based on age, sex and body mass index, to enhance usability prior to implementation into routine clinical practice. METHODS: We used data visualization techniques to modify the presentation of EQ-5D-5L outcomes data within the decision aid. The EQ-5D-5L data was divided into two parts allowing patients to compare themselves to similar individuals (1) pre-surgery and (2) 1-year post-surgery. We created 2 versions for each part and sought patient feedback on comprehension, usefulness, and visual appeal. Patients from an urban orthopedic clinic were recruited and their ratings and comments were recorded using a researcher-administered checklist. Data were managed using Microsoft Excel, R version 3.6.1 and ATLAS.ti V8 and analyzed using descriptive statistics and directed content analysis. RESULTS: A total of 24 and 25 patients participated in Parts 1 and 2, respectively. Overall, there was a slight preference for Version 1 in Part 1 (58.3%) and Version 2 in Part 2 (64%). Most participants demonstrated adequate comprehension for all versions (range 50-72%) and commented that the instructions were clear. While 50-60% of participants rated the content as useful, including knowing the possible outcomes of surgery, some participants found the information interesting only, were unsure how to use the information, or did not find it useful because they had already decided on a treatment. Participants rated visual appeal for all versions favorably but suggested improvements for readability, mainly larger font and image sizes and enhanced contrast between elements. CONCLUSIONS: Based on the results, we will produce an enhanced presentation of EQ-5D-5L data within the decision aid. These improvements, along with further usability testing of the entire decision aid, will be made before implementation of the decision aid in routine clinical practice. Our results on patients' perspectives on the presentation of EQ-5D-5L data to support decision making for TKA treatments contributes to the knowledge on EQ-5D-5L applications within healthcare systems for clinical care.

A systematic review and meta-analysis of hybrid vs. cemented stems - which method is more optimal for revision total knee arthroplasty?

INTRODUCTION: The number of primary and revision Total Knee Arthroplasty (TKA) cases are expected to increase in future. There are various advantages and disadvantage to employing either of the two main types of stem fixation methods - cemented or hybrid technique. This review aimed to study the most optimal fixation method for revision TKAs by comparing radiological outcomes and re-revision rates. METHODS: A systematic review and meta-analysis was performed using PubMed and Cochrane Library from 2010 to identify studies explicitly comparing outcomes between cemented against hybrid fixation revision TKA techniques, with a minimum follow up of at least 24 months. A total of 8 studies was included in this review. Egger's test and visual inspection of the funnel plot did not reveal publication bias. RESULTS: There was no statistically significant difference in radiological failure and loosening (OR 0.79, CI 0.37-1.66, I2 = 29%, p = 0.22), all causes of re-revision (OR 1.03, CI 0.73-1.44, I2 = 0%, p = 0.56) and aseptic revision (OR 0.74, CI 0.27-2.02, I2 = 0%, p = 0.41) between cemented and hybrid techniques. Functional and pain outcomes compared between the two fixation techniques were largely similar across the studies included in this meta-analysis. CONCLUSION: Despite a trend favouring hybrid stems in revision TKA, current evidence revealed that radiological outcomes and re-revision rates are largely similar between cemented and hybrid fixation techniques.

Comparison of the coverage and rotation of asymmetrical and symmetrical tibial components: a systematic review and meta-analysis.

BACKGROUND: An optimized fit of the tibial component to the resection platform and correct rotational alignment are critical for successful total knee arthroplasty (TKA). However, there remains controversy regarding the superiority of symmetric tibial component versus asymmetric tibial component. The objective of this systematic review and meta-analysis was to evaluate the current evidence for comparing the coverage and rotation of asymmetrical and symmetrical tibial component. METHODS: We searched potentially relevant studies form PubMed, Web of science, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and China National Knowledge Infrastructure (CNKI), up to 1 March 2023. Data extraction and quality assessment were performed by two independent reviewers. Meta-analysis was conducted using Review Manager 5.4. RESULTS: Sixteen articles were identified. Compared to symmetric tibial component, asymmetric tibial component increased the coverage of the proximal tibial cut surface (MD, -2.87; 95%CI, -3.45 to -2.28; P < 0.00001), improved the prevalence of tibial baseplate underhang (OR, 0.16; 95%CI, 0.07 to 0.33; P < 0.00001) and malrotation (OR, 0.13; 95%CI, 0.02 to 0.90; P = 0.04), and reduced the degree of tibial component rotation (MD, -3.11; 95%CI, -5.76 to -0.47; P = 0.02). But there was no statistical significance for improving tibial baseplate overhang (OR, 0.58; 95%CI, 0.08 to 3.97; P = 0.58). Additionally, no revision had occurred for the two tibial components in the included studies. CONCLUSION: The current evidence shows asymmetric tibial component offer advantages in terms of coverage and rotation compared with symmetric tibial component in TKA.

Changes in the anteroposterior position of the femur relative to the tibia impact patient satisfaction in total knee arthroplasty.

BACKGROUND: In this study, we aimed to investigate the preoperative and postoperative anteroposterior position (AP) of the femur relative to the tibia in total knee arthroplasty (TKA) and assess the influence of change in the AP position on clinical outcomes. METHODS: We evaluated 49 knees that underwent bi-cruciate-substituted TKA using a navigation system. The preoperative and postoperative AP position of the femur relative to the tibia at maximum extension, 15°, 30°, 45°, 60°, 90°, 105°, and 120° and maximum flexion angles were calculated. The 2011 Knee Society Score was evaluated preoperatively and 1 year postoperatively. The Wilcoxon signed rank and Spearman's rank correlation tests were performed, with statistical significance set at P < 0.05. RESULTS: The postoperative AP position was significantly correlated with the preoperative AP position at each measured angle. The postoperative AP positions were statistically more anterior than those preoperatively. Furthermore, the changes in the AP position after TKA negatively correlated with the symptom (P = 0.027 at 30°, P = 0.0018 at 45°, P = 0.0003 at 60°, P = 0.01 at 90°, and P = 0.028 at 105°) and patient satisfaction (P = 0.018 at 60° and P = 0.009 at 90°) scores at 1 year postoperatively. CONCLUSION: The postoperative AP position of the femur relative to the tibia was strongly influenced by the preoperative those in TKA. Postoperative anterior deviation of the femur relative to the tibia from mid-flexion to deep flexion could worsen clinical outcomes.

Artificial intelligence in total and unicompartmental knee arthroplasty.

The application of Artificial intelligence (AI) and machine learning (ML) tools in total (TKA) and unicompartmental knee arthroplasty (UKA) emerges with the potential to improve patient-centered decision-making and outcome prediction in orthopedics, as ML algorithms can generate patient-specific risk models. This review aims to evaluate the potential of the application of AI/ML models in the prediction of TKA outcomes and the identification of populations at risk.An extensive search in the following databases: MEDLINE, Scopus, Cinahl, Google Scholar, and EMBASE was conducted using the PIOS approach to formulate the research question. The PRISMA guideline was used for reporting the evidence of the data extracted. A modified eight-item MINORS checklist was employed for the quality assessment. The databases were screened from the inception to June 2022.Forty-four out of the 542 initially selected articles were eligible for the data analysis; 5 further articles were identified and added to the review from the PUBMED database, for a total of 49 articles included. A total of 2,595,780 patients were identified, with an overall average age of the patients of 70.2 years ± 7.9 years old. The five most common AI/ML models identified in the selected articles were: RF, in 38.77% of studies; GBM, in 36.73% of studies; ANN in 34.7% of articles; LR, in 32.65%; SVM in 26.53% of articles.This systematic review evaluated the possible uses of AI/ML models in TKA, highlighting their potential to lead to more accurate predictions, less time-consuming data processing, and improved decision-making, all while minimizing user input bias to provide risk-based patient-specific care.

Prolonged efficacy of cefazolin in intraosseous regional prophylaxis for total knee arthroplasty: a rabbit model study.

BACKGROUND: A novel approach known as intraosseous regional administration (IORA) has emerged as a technique for delivering prophylactic antibiotics, and it results in higher tissue concentrations around the knee. It is hypothesized that IORA of cefazolin for antibiotic prophylaxis during total knee arthroplasty will result in sustained effective levels for a longer duration. The aim of the current study was to investigate temporal changes in peri-knee cefazolin blood concentrations after IORA of cefazolin. METHODS: Twelve rabbits were randomly divided into two groups, with six rabbits in each group. In control group a single intravenous bolus injection of cefazolin (10 mL, 100 mg) was administered into the marginal ear vein. In experimental groupexperimental group the same dose of cefazolin was injected into the left tibial marrow cavity after tourniquet inflation at the base of the left thigh. Blood samples were collected periodically at different timepoints, and cefazolin concentrations were determined. RESULTS: The intraosseous treatment resulted in significant differences in plasma cefazolin concentrations at all timepoints. Experimental group exhibited higher plasma cefazolin concentrations than control group. CONCLUSIONS: Cefazolin in intraosseous regional prophylaxis exhibits effectiveness in intraoperative antibiotic prophylaxis by maintaining concentrations above the minimum inhibitory concentration for extended durations, rather than relying solely on high concentrations.

Factors to improve odds of success following medial opening-wedge high tibial osteotomy: a machine learning analysis.

BACKGROUND: Although high tibial osteotomy (HTO) is an established treatment option for medial compartment osteoarthritis, predictive factors for HTO treatment success remain unclear. This study aimed to identify informative variables associated with HTO treatment success and to develop and internally validate machine learning algorithms to predict which patients will achieve HTO treatment success for medial compartmental osteoarthritis. METHODS: This study retrospectively reviewed patients who underwent medial opening-wedge HTO (MOWHTO) at our center between March 2010 and December 2015. The primary outcomes were a lack of conversion to total knee arthroplasty (TKA) and achievement of a minimal clinically important difference of improvement in the Knee Injury and Osteoarthritis Outcome Score (KOOS) at a minimum of five years postoperatively. Recursive feature selection was used to identify the combination of variables from an initial pool of 25 features that optimized model performance. Five machine learning algorithms (XGBoost, multilayer perception, support vector machine, elastic-net penalized logistic regression, and random forest) were trained using five-fold cross-validation three times and applied to an independent test set of patients. The performance of the model was evaluated by the area under the receiver operating characteristic curve (AUC). RESULTS: A total of 231 patients were included, and 200 patients (86.6%) achieved treatment success at the mean of 9 years of follow-up. A combination of seven variables optimized algorithm performance, and the following specific cutoffs increased the likelihood of MOWHTO treatment success: body mass index (BMI) ≤ 26.8 kg/m2, preoperative KOOS for pain ≤ 46.0, preoperative KOOS for quality of life ≤ 33.0, preoperative International Knee Documentation Committee score ≤ 42.0, preoperative Short-Form 36 questionnaire (SF-36) score > 42.25, three-month postoperative hip-knee-ankle angle > 1.0°, and three-month postoperative medial proximal tibial angle (MPTA) > 91.5° and ≤ 94.7°. The random forest model demonstrated the best performance (F1 score: 0.93; AUC: 0.81) and was transformed into an online application as an educational tool to demonstrate the capabilities of machine learning. CONCLUSIONS: The random forest machine learning algorithm best predicted MOWHTO treatment success. Patients with a lower BMI, poor clinical status, slight valgus overcorrection, and postoperative MPTA < 94.7 more frequently achieved a greater likelihood of treatment success. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Epidemiology and prognostic factors for new-onset deep venous thrombosis after unicompartmental knee arthroplasty: a retrospective study.

BACKGROUND: Patients who underwent knee joint arthroplasty were at risk of venous thromboembolic events (VTEs), however, less studies were conducted to demonstrate the epidemiology and risk factors of deep venous thrombosis (DVT) following unicompartmental knee arthroplasty (UKA). Objective of this study was to explore the incidence and prognostic factors of DVT after UKA. METHODS: Patients who underwent primary UKA from December 2018 to June 2022 were recruited in this study. Demographic characteristics, operation related variables and laboratory index were extracted and analyzed. Receiver operating characteristic analysis was performed to detect the optimum cut-off value for variables of interest. Univariate and multivariate logistic analysis were performed to identify risk factors of DVT. RESULTS: 351 UKAs with a mean age of 65.4 ± 7.1 years were reviewed. After 12.9 ± 11.2 months follow-up, 35 DVTs were confirmed which indicating an incidence of 9.9%. The results showed that occupation (agricultural laborer) (P = 0.008), disease duration > 8.5 years (P = 0.035), operation time > 169 min (P = 0.003), intraoperative blood loss > 102 ml (P < 0.001), BMI > 26.8 kg/m 2 (P = 0.001), preoperative D-dimer > 0.29 mg/L (P = 0.001), prothrombin time < 10.7 s (P = 0.033) and INR < 0.98 (P = 0.032) between DVT and Non-DVT group were significantly different. Multivariate logistic regression analysis showed intraoperative blood loss > 102 ml (OR, 3.707; P, 0.001), BMI > 26.8 kg/m 2 (OR, 4.664; P, 0.004) and D-dimer > 0.29 mg/L (OR, 2.882; P, 0.009) were independent risk factors of DVT after UKA. CONCLUSION: The incidence of DVT in the present study was 9.9%, extensive intraoperative blood loss, advanced BMI and high level of D-dimer would increase the risk of lower extremity thrombosis by 2-4 times.