Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Objective:To detect the microbial signals in the synovial fluid from knee osteoarthritis (KOA) patients using long-read metagenomic sequencing and assess the impact of intra-articular injection of sodium hyaluronate on the detection.Methods:This retrospective study enrolled 28 KOA patients [set as a KOA group: 13 males, 15 females; mean age of (65.5±5.7) years] who had undergone primary total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA) at Department of Knee Joint Surgery, Honghui Hospital between January 2021 and January 2023. At the same time, samples of instrument cleaning water used for the 28 KOA patients were collected (set as a rinse solution group), and the knee synovial fluid was collected from 10 healthy adult volunteers [set as a control group: 5 males and 5 females; mean age of (29.7±12.1) years]. The KOA patients were stratified into an injection group ( n=5) and a non-injection group ( n=23) according to the history of injection of sodium hyaluronate within 6 months before operation. All samples were subjected to standard procedures for nucleic acid extraction and Oxford Nanopore Technologies (ONT) metagenomic sequencing to compare microbial taxa and detection frequencies. Results:No periprosthetic joint infections or infection-related clinical events occurred in the KOA patients during the 12-month postoperative follow-up. A total of 10 microbial species (30 isolates) were identified in the KOA synovial fluid (5 Gram-positive and 5 Gram-negative). The species with the top 5 detection rates were Escherichia coli (20.0%), Propionibacterium spp. (20.0%), Staphylococcus spp. (16.7%), Acinetobacter spp. (13.3%), and Pseudomonas spp. (6.7%). From the samples in the rinse solution group, 9 species (11 isolates) were detected, reflecting background contamination. All the joint fluid from the healthy volunteers in the control group was negative. Six species of microorganisms were detected in the injection group while 3 species in the non-injection group, showing a statistically significant difference ( P<0.001). Conclusions:Long-read metagenomic sequencing detects diverse microbial signatures in the synovial fluid from KOA patients, and preoperative injection of sodium hyaluronate is associated with increased detection of microbial species.

Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Objective:To detect the microbial signals in the synovial fluid from knee osteoarthritis (KOA) patients using long-read metagenomic sequencing and assess the impact of intra-articular injection of sodium hyaluronate on the detection.Methods:This retrospective study enrolled 28 KOA patients [set as a KOA group: 13 males, 15 females; mean age of (65.5±5.7) years] who had undergone primary total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA) at Department of Knee Joint Surgery, Honghui Hospital between January 2021 and January 2023. At the same time, samples of instrument cleaning water used for the 28 KOA patients were collected (set as a rinse solution group), and the knee synovial fluid was collected from 10 healthy adult volunteers [set as a control group: 5 males and 5 females; mean age of (29.7±12.1) years]. The KOA patients were stratified into an injection group ( n=5) and a non-injection group ( n=23) according to the history of injection of sodium hyaluronate within 6 months before operation. All samples were subjected to standard procedures for nucleic acid extraction and Oxford Nanopore Technologies (ONT) metagenomic sequencing to compare microbial taxa and detection frequencies. Results:No periprosthetic joint infections or infection-related clinical events occurred in the KOA patients during the 12-month postoperative follow-up. A total of 10 microbial species (30 isolates) were identified in the KOA synovial fluid (5 Gram-positive and 5 Gram-negative). The species with the top 5 detection rates were Escherichia coli (20.0%), Propionibacterium spp. (20.0%), Staphylococcus spp. (16.7%), Acinetobacter spp. (13.3%), and Pseudomonas spp. (6.7%). From the samples in the rinse solution group, 9 species (11 isolates) were detected, reflecting background contamination. All the joint fluid from the healthy volunteers in the control group was negative. Six species of microorganisms were detected in the injection group while 3 species in the non-injection group, showing a statistically significant difference ( P<0.001). Conclusions:Long-read metagenomic sequencing detects diverse microbial signatures in the synovial fluid from KOA patients, and preoperative injection of sodium hyaluronate is associated with increased detection of microbial species.

Objective To assess the diagnostic efficacy of extracellular volume fraction(fECV)based on multi-slice spiral CT in evaluating lymph node metastasis of pancreatic ductal adenocarcinoma.Methods A total of 74 patients diagnosed as pancreatic ductal adenocarcinoma from March 2018 to March 2023 in the First Hospital of Jiaxing were retrospectively collected.All patients underwent enhanced multi-slice spiral CT examination.Hematocrit was collected before examination.CT values at the plain phase,portal phase,the equilibrium phase of the lesion and CT values of abdominal aorta at the same level were respectively measured after examination,and fECV was calculated.Using postoperative pathological results as the"gold standard",the efficacy of fECV in diagnosing lymph node metastases of pancreatic ductal adenocarcinoma was evaluated by receiver operating characteristic curve.Results There were 33 cases with lymph node metastasis in positive group and 41 cases in negative group.There was no statistically significant difference in fECV at the portal phase between lymph node metastasis positive group and negative group(t=0.80,P＞0.05).There was statistically significant difference in fECV at the equilibrium phase between positive and negative lymph node metastasis group(t=2.84,P＜0.001).The area under the curve of lymph node metastasis in portal phase and equilibrium phase were 0.517 and 0.870,respectively.Conclusion The fECV based on multi-slice spiral CT equilibrium phase can evaluate lymph node metastasis of pancreatic ductal adenocarcinoma.

Objective To investigate serum levels of soluble apoptosis-related factor ligand(sFasL)and stromal cell derived factor 1(SDF-1)in patients with aplastic anemia(AA)and their correlation with immunosuppressive treatment.Methods Forty-three AA patients who received immunosuppressive therapy for half a year were selected as the observation group,and another 43 healthy subjects at the same period were selected as the control group.Patients in the observation group received immunosuppressive therapy and hematopoietic propoietic therapy,and patients were divided into the ineffective group and the effective group according to the efficacy.Clinical data of patients were collected,and serum levels of sFasL,SDF-1,tumor necrosis factor-α(TNF-α)and interleukin-8(IL-8)were detected by enzyme-linked immunosorbent assay.The correlation between serum sFasL and SDF-1 levels was analyzed.Multivariate Logistic regression analysis was conducted to analyze influencing factors of immunosuppressive treatment in AA patients.The predictive values of serum sFasL and SDF-1 on immunosuppressive treatment were analyzed by receiver operating characteristic(ROC)curve.Results Serum levels of sFasL and SDF-1 were higher in the observation group than those in the control group(P＜0.05).Serum levels of TNF-α,IL-8,sFasL and SDF-1 were higher in the ineffective group than those in the effective group(P＜0.05).Serum sFasL level was positively correlated with SDF-1 level in AA patients(r=0.534,P＜0.001).Increased serum sFasL and SDF-1 levels were independent risk factors for ineffective immunosuppressive therapy in AA patients(P＜0.05).The area under the curve(AUC)of serum sFasL and SDF-1 combined to predict the immunosuppressive treatment effect of AA patients was 0.973(95%CI:0.872-0.999),which was better than that of single diagnosis(P＜0.05),and its sensitivity and specificity were 94.44%and 96.00%,respectively.Conclusion Serum levels of sFasL and SDF-1 are significantly increased in patients with AA.The combined detection of sFasL and SDF-1 has high predictive value for the immunosuppressive treatment effect of AA.

BACKGROUND:In recent years,tranexamic acid has been extensively used to mitigate the substantial blood loss associated with total knee arthroplasty.However,the optimal method of topical application has not yet been established. OBJECTIVE:To evaluate the effectiveness and safety of intraoperative topical application of tranexamic acid combined with physical compression dressing in reducing perioperative blood loss in total knee arthroplasty. METHODS:A retrospective analysis was conducted on 90 patients who underwent total knee arthroplasty at the Honghui Hospital in Xi'an from January 2021 to December 2022.Based on the different topical use methods of tranexamic acid during surgery,patients were divided into three groups,with 30 cases in each group.In the compression dressing group,2 g of tranexamic acid was placed in the articular cavity,and after packing the wound with gauze and cotton pads,a bandage was used to compress the wound.In the periarticular injection group,2 g of tranexamic acid was injected into the surrounding tissue of the articular cavity.In the intra-articular injection group,2 g of tranexamic acid was injected into the articular cavity.The blood loss,operation time,coagulation indicators,inflammatory indicators,and postoperative complications of the three groups were statistically analyzed. RESULTS AND CONCLUSION:(1)In terms of total blood loss,hidden blood loss,and maximum hemoglobin drop,the periarticular injection group had the least amount,and there was no statistically significant difference between the compression dressing group and periarticular injection group(P>0.05).In terms of intraoperative blood loss,the compression dressing group had the least amount,and there were statistically significant differences compared with the periarticular injection group and intra-articular injection group(P<0.05).There was no statistically significant difference in operation time among the three groups(P>0.05).(2)There were no statistically significant differences in coagulation indicators(D-dimer and fibrinogen degradation products)and inflammation indicators(C-reactive protein and erythrocyte sedimentation rate)among the three groups preoperatively and on the first and third days after operation(P>0.05).(3)There was no statistically significant difference observed among the three groups in terms of slow blood flow in the affected limb,intramuscular venous thrombosis,soft tissue swelling,and incidence of wound complications(P>0.05).Additionally,no cases of deep vein thrombosis or pulmonary embolism were detected in any of the groups.(4)The topical application of tranexamic acid combined with compression dressing achieves the same effect as a periarticular injection in terms of simplicity of operation and reduced perioperative blood loss.This method also avoids the trauma caused by repeated punctures and does not increase the incidence of postoperative complications,making it a worthwhile option for clinical promotion.

Objective:To evaluate the mechanical performance of customized metal prosthesis with tibia stems of varying lengths for tibial bone defects reconstruction.Methods:Morphologically matched postoperative finite element models of bone defect revision were developed, with three gradients (15 mm, 30 mm, and 45 mm) according to the degree of bone defect and were reconstructed with 3D printed tantalum metal prosthesis using three tibial stem lengths (80 mm, 120 mm, and 150 mm), respectively. Conventional static and dynamic (walking gait) loading was performed to analyze the peak tibial stress distribution and accumulated sliding distance at the prosthetic interface, and to assess the effects of the three tibial stems of different lengths on the stability of the customized tibial defect restorations and the internal tibial stress state.Results:The peak accumulated sliding distance of the dynamically loaded morphologically matched restorations ranged from 17.94 to 21.31 mm with static loading, which were 68% to 84.3% higher than those of 10.26 to 11.69 mm with static loading. The peak tibial stresses in the dynamically loaded model were greater than those in the statically loaded model, with an increase of 28%-49.2%, including 132.94-143.88 MPa in the statically loaded model and 170.41-200.14 MPa in the dynamically loaded model. The overall accumulated sliding distance of the tibia prosthetic model gradually decreased from the tibial osteotomy surface, and the accumulated peak sliding distances ranged from 10.26 to 11.69 mm for static loading, and from 17.94 to 21.31 mm for dynamic loading. The bone tissue stresses in the anterolateral and medial-posterior tibia increased gradually from top to bottom, and the maximum stress value in each section was in the posterior medial tibia (the maximum value was 200.14 MPa). The highest bone tissue stress in the lateral tibia was affected by the tibial stem length, which resulted in a different location, and it was the area most affected by stress shielding (maximum value of 170.65 MPa).Conclusion:For stability assessment of morphologically matched tantalum customized prosthesis, physiological gait dynamic loading studies are more reliable than static loading; the choice of tibial stem length depends on a combination of accumulated peak sliding distances and tibial bone stress distribution factors.

Objective:To explore the application value of Oxford nanopore technologies (ONT) in the diagnosis and treatment of periprosthetic joint infection (PJI).Methods:A prospective analysis was conducted on 32 patients with PJI admitted to the joint department of Xi'an Honghui Hospital from October 2021 to March 2023, who met the 2018 PJI diagnostic criteria of the American Skeletal Infection Society (MSIS), including 15 males and 17 females with an average age of 63.93±8.93 years. 32 revision patients who did not meet the 2018 MSIS PJI criteria during the same period were collected as controls (non PJI group), including 13 males and 19 females with an average age of 65.53±8.54 years. All patients underwent joint fluid puncture before or during surgery, and the specimens were tested by ONT, metagenomic next generation sequencing (mNGS), and general microbial culture. The receiver operating characteristic (ROC) curves were drawn for both groups, and the sensitivity, specificity, positive predictive value, negative predictive value, and Youden index of the three detection techniques were calculated and compared to evaluate the detection efficiency of different detection methods in PJI.Results:Among the 32 patients with PJI, 30 were positive for ONT, with a total of 30 pathogenic bacteria detected, and the detection time was 22.37±8.36 h. 31 were positive for mNGS, with a total of 33 bacterial species detected, and the detection time was 46.25±9.36 h. 17 were positive for microbial culture, with a total of 8 bacterial species detected, and the detection time was 96.23±15.62 h. Among the 32 patients with non PJI group, 1 was positive for ONT and 5 were positive for mNGS, with a total of 1 and 3 bacterial species detected, respectively. The results of microbial culture were all negative. The detection time and area under the curve (AUC) of ONT and mNGS were 22.37±8.36 h and 0.953[95% CI (0.901, 1.006)], 46.25±9.36 h and 0.906[95% CI (0.835, 0.977)], respectively, which were better than those of microbial culture 96.23±15.62 h and 0.766[95% CI (0.678, 0.853)], and the difference was statistically significant ( P<0.05). The sensitivity of ONT, mNGS, and microbial culture were 0.938, 0.969, and 0.531, respectively, and the specificity was 0.969, 0.844, and 1.000, respectively. The Jordan index was 0.906, 0.813, and 0.531, respectively. Conclusion:ONT testing has higher diagnostic efficacy than mNGS and microbial culture in the diagnosis of PJI, and also has advantages in detection time. It also suggests that some PJI are not caused by a single microbial infection.

Objective:To analyze the predictive value of magnetic resonance imaging (MRI) examination in secondary dementia of cognitive impairment of patients with Parkinson disease (PD). Methods:A total of 100 PD patients with cognitive dysfunction,who admitted to the Affiliated Suzhou Hospital of Nanjing University Medical School and the Second Affiliated Hospital of Soochow University,were selected. They were divided into observation group (30 cases) and control group (70 cases) according to the Hasegawa Dementia Scale (HDS) score. The HDS score of observation group was ≤ 21.5 points,which had occurred secondary dementia,while the HDS score of control group was>21.5 points,which had not occurred secondary dementia. The imaging parameters,which included apparent diffusion coefficient (ADC) and fractional anisotropy (FA) index of magnetic resonance imaging (MRI),between two groups were compared. Logistic regression analysis was used to identify the risk factors for secondary dementia of PD patients with cognitive impairment. Receiver operating characteristic (ROC) curve was used to analyze the predictive efficacy of MRI imaging parameters for the secondary dementia of PD patients with cognitive impairment. Results:Compared with substantia nigra of the control group,the observation group had higher ADC values and lower FA values in substantia nigra,and the differences of them between the two groups were statistically significant (t=2.837,4.581,P<0.05),respectively. The ADC value and FA value of substantia nigra,age,PD duration and homocysteine (Hcy) were risk factors for the secondary dementia of cognitive impairment of PD patients (OR=1.537,1.346,1.134,1.351,1.625,P<0.05),respectively. The area under curve (AUC) value,sensitivity,specificity of the combined detection of ADC value and FA value of substantia nigra were respectively 0.861,94.86％ and 82.18％ in predict the secondary dementia of cognitive impairment of PD patients,and the predictive efficiency of combined detection was higher (95％CI:0.812-0.960,P<0.05). Conclusion:The increase of ADC value and the decrease of FA value of substantia nigra closely relate to the secondary dementia of cognitive dysfunction of PD patients. The combined detection of ADC value and FA value of substantia nigra can improve predictive efficiency of dementia.