Objective To explore the mechanism of antibiotic delivery system targeting bacterial biofilm with linezolid (LZD) based on ε-poly-L-lysine (ε-PLL) and cyclodextrin (CD) (ε-PLL-CD-LZD), aiming to enhance antibiotic bioavailability, effectively penetrate and disrupt biofilm structures, and thereby improve the treatment of bone and joint infections. Methods ε-PLL-CD-LZD was synthesized via chemical methods. The grafting rate of CD was characterized using nuclear magnetic resonance. In vitro biocompatibility was evaluated through live/dead cell staining after co-culturing with mouse embryonic osteoblast precursor cells (MC3T3-E1), human umbilical vein endothelial cells, and mouse embryonic fibroblast cells (3T3-L1). The biofilm-enrichment capacity of ε-PLL-CD-LZD was assessed using Staphylococcus aureus biofilms through enrichment studies. Its biofilm eradication efficacy was investigated via minimum inhibitory concentration (MIC) determination, scanning electron microscopy, and live/dead bacterial staining. A bone and joint infection model in male Sprague-Dawley rats was established to validate the antibacterial effects of ε-PLL-CD-LZD. Results In ε-PLL-CD-LZD, the average grafting rate of CD reached 9.88%. The cell viability exceeded 90% after co-culturing with three types cells. The strong biofilm enrichment capability was observed with a MIC of 2 mg/L. Scanning electron microscopy observations revealed the effective disruption of biofilm structure, indicating potent biofilm eradication capacity. In vivo rat experiments demonstrated that ε-PLL-CD-LZD significantly reduced bacterial load and infection positivity rate at the lesion site (P<0.05). ConclusionThe ε-PLL-CD antibiotic delivery system provides a treatment strategy for bone and joint infections with high clinical translational significance. By effectively enhancing antibiotic bioavailability, penetrating, and disrupting biofilms, it demonstrated significant anti-infection effects in animal models.
Objective To compare the effectiveness of the intermittent suture and the cosmetic suture in total knee arthroplasty (TKA). Methods A clinical data of 48 patients with knee osteoarthritis, who underwent initial TKA between January 2017 and April 2018, was retrospectively analyzed. Among them, 23 patients underwent intermittent suture (group A) and 25 patients underwent cosmetic suture (group B). There was no significant difference in gender, age, body mass index, disease duration, degrees of varus and valgus deformities, knee society score (KSS), visual analogue scale (VAS) score, and levels of interleukin-6 (IL-6), procalcitonin (PCT), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) in serum before operation between the two groups (P>0.05). KSS scores at 1 and 6 months after operation were used to assess the knee function. VAS scores at 1, 3, and 5 days after operation were used to assess the pain degree of knee. Levels of IL-6, PCT, CRP, and ESR in serum at 1 day and 1 month after operation were recorded to evaluate the risk of periprosthetic infection. Likert score at 6 months after operation was used to evaluate the satisfaction of incision. The hospitalization time after operation was also recorded. Results All patients were followed up 7- 17 months (mean, 11.3 months). There was no significant difference in hospitalization time after operation between two groups (t=−1.907, P=0.063). The Likert score in group A was significantly lower than that in group B (t=−2.196, P=0.033). The VAS score, KSS clinical score and KSS functional score at different time points after operation were significantly better than those before operation in two groups (P<0.05). The VAS score at 5 days after operation was better than that at 1 day after operation in two groups, and the KSS clinical score and KSS functional score at 6 months after operation were better than those at 1 month after operation in two groups, all showing significant differences (P<0.05). The VAS scores at 3 and 5 days after operation were significantly lower in group B than in group A (P<0.05), and there was no significant difference in VAS score and KSS scores between two groups at other time points after operation (P>0.05). There was no significant difference in the levels of IL-6, PCT, CRP, and ESR between the two groups at different time points after operation (P>0.05). Conclusion Cosmetic suture is superior to intermittent suture in incision appearance and pain management, but there is no significant difference in short-term joint function and risk of periprosthetic infection after TKA.
Objective To investigate the diagnostic efficacy of silkworm larvae plasma (SLP) colorimetry in the accurate diagnosis of periprosthetic joint infection (PJI). Methods Ninety healthy male New Zealand white rabbits were used for knee arthroplasty with Swanson prosthesis. Then they were randomly divided into 3 groups according to different pathogenic bacteria: group A (Staphylococcus aureus group), group B (Staphylococcus epidermidis group) and group C (Escherichia coli group), with 30 rats in each group. The PJI model was prepared by knee injection with 1 mL of pathogenic bacteria of different concentrations. Samples were taken before inoculation and at 7, 14, and 21 days after inoculation, and based on the 2018 PJI Philadelphia International Consensus diagnostic criteria, the success rate of modeling among 3 groups of experimental animals was determined. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic efficiency of SLP colorimetry were calculated. Results At 21 days after inoculation, 26, 18, and 23 rabbits in groups A, B, and C were diagnosed as infection, respectively. The success rates of modeling were 86.7%, 60.0%, and 76.7%, respectively, showing no significant difference among the 3 groups (χ2=5.724, P=0.073). The results of PJI colorimetry showed that 1 false-positive animal (specificity 75.0%) appeared in group A at 7 days, and the specificity of SLP increased to 100.0% over time (on 14 and 21 days); on 14 and 21 days, another animal appeared false-negative results (sensitivity decreased from 100.0% to 96.2%). One false-positive animal appeared in group B at 7 days (specificity 91.7%), the specificity returned to 100.0% over time; 1 and 4 false-negative animals appeared at 14 and 21 days, respectively (sensitivity 94.4% and 83.3%, respectively). In group C, two false-positive animals (specificity 71.4%) were found at 7 days, and then returned to 100.0%. The diagnostic efficiency of groups A and C was very high at 21 days (96.7% and 100.0%), even for the low virulence Staphylococcus epidermidis in group B, the diagnostic efficiency could be maintained at 90.0% (21 days), and the overall diagnostic efficiency was very good (95.6%). Conclusion SLP colorimetry has high sensitivity, specificity, and diagnostic efficiency in the diagnosis of PJI, which is a potential diagnostic method.
ObjectiveTo explore the clinical value of metagenomic next-generation sequencing (mNGS) in diagnosis and treatment of periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). MethodsBetween April 2020 and March 2023, 10 patients with PJI after TKA were admitted. There were 3 males and 7 females with an average age of 69.9 years (range, 44-83 years). Infection occurred after 8-35 months of TKA (mean, 19.5 months). The duration of infection ranged from 16 to 128 days (mean, 37 days). The preoperative erythrocyte sedimentation rate (ESR) was 15-85 mm/1 h (mean, 50.2 mm/1 h). The C reactive protein (CRP) was 4.4-410.0 mg/L (mean, 192.8 mg/L). The white blood cell counting was (3.4-23.8)×109/L (mean, 12.3×109/L). The absolute value of neutrophils was (1.1-22.5)×109/L (mean, 9.2×109/L). After admission, the joint fluid was extracted for bacterial culture method and mNGS test, and sensitive antibiotics were chosen according to the results of the test, and the infection was controlled in combination with surgery. Results Seven cases (70%) were detected as positive by bacterial culture method, and 7 types of pathogenic bacteria were detected; the most common pathogenic bacterium was Streptococcus lactis arrestans. Ten cases (100%) were detected as positive by mNGS test, and 11 types of pathogenic bacteria were detected; the most common pathogenic bacterium was Propionibacterium acnes. The difference in the positive rate between the two methods was significant (P=0.211). Three of the 7 patients who were positive for both the bacterial culture method and the mNGS test had the same results for the type of pathogenic bacteria, with a compliance rate of 42.86% (3/7). The testing time (from sample delivery to results) was (4.95±2.14) days for bacterial culture method and (1.60±0.52) days for mNGS test, and the difference was significant (t=4.810, P<0.001). The corresponding sensitive antibiotic treatment was chosen according to the results of bacterial culture method and mNGS test. At 3 days after the one-stage operation, the CRP was 6.8-48.2 mg/L (mean, 23.6 mg/L); the ESR was 17-53 mm/1 h (mean, 35.5 mm/1 h); the white blood cell counting was (4.5-8.1)×109/L (mean, 6.1×109/L); the absolute value of neutrophils was (2.3-5.7)×109/L (mean, 4.1×109/L). All patients were followed up 12-39 months (mean, 23.5 months). One case had recurrence of infection at 6 months after operation, and the remaining 9 cases showed no signs of infection, with an infection control rate of 90%. Conclusion Compared with bacterial culture method, mNGS test can more rapidly and accurately detect pathogenic bacteria for PJI after TKA, which is important for guiding antibiotics combined with surgical treatment of PJI.
Objective To evaluate the effectiveness of Ilizarov technique and tibiotalar or tibiocalcanean arthrodesis for one-stage treatment of ankle joints infection and bone defects. Methods Between January 2014 and April 2016, 14 patients with ankle joints infection and bone defects were treated by Ilizarov technique and tibiotalar or tibiocalcanean arthrodesis for one-stage. There were 12 males and 2 females with an average age of 39.8 years (range, 25-61 years). The causes of ankle infection included falling from height injury in 5 cases, falling injury in 4 cases, traffic accident injury in 1 case, crushing injury in 1 case, sprain injury in 1 case, and hematogenous reason in 2 cases. All the patients received surgery for 0-8 times (mean, 3.7 times) before admission. The modified American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score was 30.25±3.54 before operation. The disease duration was 1-30 months (mean, 10.3 months). Results All the incisions healed by first intension without recurrence of infection, and two-stage bone grafting operation did not performed. One case felt slight local pain and swell of ankle joint after weight-bearing walking more than 30 minutes, and without special treatment. All the patients had different degree skin redness and swelling of Kirschner wire pinhole for 0-3 times, and relieved after symptomatic treatment. All the patients were followed up 6-27 months (mean, 16.8 months). Except for 2 cases who did not remove the external fixator (with external fixation time of 6 months and 8 months respectively), the other patients removed the external fixator at 6-14 months (mean, 9 months) after operation, all patients recovered the walk function and without ankle pain. The modified AOFAS ankle and hindfoot score after removal of external fixator (70.92±1.0) was significantly higher than preoperative one (t=–10.992, P=0.000). Conclusion It is a simple and effective method for one-stage treatment of ankle joints infection and bone defects by Ilizarov technique and tibiotalar or tibiocalcanean arthrodesis.
ObjectiveTo provide the evidence for diagnosis and treatment of the complication by describing the distribution and drug sensitivity of pathogens in patients with prosthetic joint infection (PJI) after primary total knee arthroplasty (TKA). MethodsBetween January 2003 and June 2013,65 cases (65 knees) with PJI after primary TKA were treated.There were 28 males and 37 females with an average age of 63.2 years (range,37-80 years).The median interval between PJI and primary TKA was 2.8 years (range,2 weeks to 11 years),including 29 left knees and 36 right knees.Prosthesis loosening could be found in 27 cases by X-ray examination.The average value of C-reactive protein and erythrocyte sedimentation rate was 37.4 mg/L (range,12.5-197.0 mg/L) and 63.2 mm/1 h (range,29.3-73.8 mm/1 h) respectively.Preoperative and intraoperative synovial fluid as well as intraoperative tissue samples should be submitted for aerobic and anaerobic culture.The four types of infections were made according to the Tsukayama et al.classification standards. ResultsThe patients were all diagnosed as having PJI.There were 5(7.69%) type I infections,4(6.15%) type ⅡA,8(12.31%) type ⅡB,3(4.62%) type Ⅲ,and 45(69.23%) type IV according to the Tsukayama et al.classification standard.Bacterial culture results were negative in 12 cases and positive in 53 cases,the main pathogen was Gram-positive cocci (39/53).The most common organism identified was Coagulase-negative Staphylococcus (24/53) followed by Staphylococcus Aureus (12/53).Resistant bacterium accounted for 61.11%(22/36) of Staphylococcus.These bacterium were all sensitive to vancomycin,linezolid,meropenem,and fluconazole;and highly resistant to erythrocin,penicillin,and cefoxitin.The main pathogenic bacteria of Coagulase-negative Staphylococcus and Staphylococcus aureus had highest resistant rate to penicillin. ConclusionGram-positive cocci is the main pathogen in patients with PJI after primary TKA,which is highly resistant to penicillin and macrolides.Antibiotic treatment of this complication should be based on the result of drug sensitivity test,vancomycin and linezolid may be used before the result of drug sensitivity test.It is important to pay attention to rare and multiple resistant bacteria.
It has been certificated that hip and knee arthroplasty can improve quality of life and relieving pain and discomfort for ageing population and patients with muscloskeletal disorders. However, the outcomes of prosthetic joint infections (PJI) after arthroplasty usually are disastrous. The incidence of PJI is lower, but the number of this population is huge, which makes the strong impacts on quality of life for patients and healthcare economics. This review discusses the prevention strategies of PJI based on clinical epidemiology, diagnostic definition, pathogenesis, microbiology and risk factors, combined with some guidelines for prevention surgical site infections published recently.
ObjectiveTo summarize the recent progress in prevention of prosthetic joint infection (PJI) so as to provide clinical references. MethodsThe publications concerning the etiology and surgical management of PJI were reviewed, analyzed, and summarized. ResultsThe prevention of PJI is related to preoperative, intraoperative, and postoperative aspects of PJI, comprehensive treatment is considered to be the most common method for PJI. ConclusionThese prevention strategies that may be utilized in all phases of perioperative care, a multifaceted approach to the patient undergoing total joint replacement will have the greatest positive effect
ObjectiveTo explore the clinical characters and histopathologic differences between patients with culture-positive and culture-negative prosthetic joint infection (PJI). MethodsBetween January 2012 and July 2013, 66 PJI patients in accord with diagnostic criteria were enrolled. According to the results of preoperative aspiration and intraoperative cultures, the patients were divided into culture-negative group (CN group, n=21) and culture-positive group (CP group, n=45). There was no significant difference in gender, age, height, weight, and body mass index between 2 groups (P>0.05). Preoperative C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and prosthesis survival time were compared between 2 groups. Intraoperative frozen sections and paraffin sections were both performed to identify infections, and histological typing was performed according to Morawietz's methods. ResultsThe preoperative CRP was (1.29±1.84) mg/ dL in CN group and (5.08±9.57) mg/dL in CP group, showing significant difference (t=2.094, P=0.038). The preoperative ESR was (22.86±28.42) mm/1 h in CN group and (36.74±31.26) mm/1 h in CP group, showing significant difference (t=7.761, P=0.000). The median survival time of prosthesis was 72 months (range, 8-504 months) in CN group and 25 months (range, 15 days-300 months) in CP group, showing significant difference (U=2.231, P=0.026). Morawietz's histological typing results showed that 2 cases were rated as type I, 7 cases as type II, and 12 cases as type III in CN group; 6 cases were rated as type I, 25 cases as type II, 13 cases as type III, and 1 case as type IV in CP group. The positive culture rate was 68.18% (45/66), and pathogenic bacteria was dominated by Staphylococcus, accounting for 68.89%. ConclusionThe patients with culture-negative PJI have slow onset and mild inflammatory response, so comprehensive diagnosis should be made based on pathological detection, laboratory examination, and intraoperative cultures.
ObjectiveTo summarize the research progress of two-stage revision for periprosthetic joint infection (PJI) after hip and knee arthroplasties.MethodsThe related literature on two-stage revision for PJI was summarized, and the new progress in the choice of spacers, systemic antibiotic therapy, and risk factors were analyzed.ResultsTwo-stage revision is a common way to treat infection after hip and knee arthroplasties. The types of spacers used in the one-stage operation are diverse and each has its own advantages and disadvantages. Non-articular spacers are mainly used for the patients with poor soft tissue conditions around the joints and severe bone defects. But the joint mobility is not good after the placement of the spacer. Articular spacers can restore the affected joint movement after operation, which is beneficial to the joint mobility after two-stage operation. The use of antibiotics is an indispensable part of the treatment process, and the effectiveness of short-term antibiotic treatment is similar to long-term treatment. Identifying the relevant risk factors that influence the prognosis of the two-stage revision can help preoperative management and reduce the recurrence rate of infection.ConclusionThere are still controversies about the choice of spacers and systemic antibiotic therapy during the two-stage revision and treatment of PJI. The factors affecting the prognosis of the two-stage revision need to be explored and the further high-quality research is needed.