Use of 1.5-Stage Functional Articulating Hip Spacers for Two-Stage Treatment of Hip Infection.

BACKGROUND: A two-stage treatment is commonly used for chronic hip infections. This study compared the clinical efficacy and complications associated with 1.5-stage functional articulating hip spacers (FAHS) and handmade spacers utilized during two-stage treatment. METHODS: This retrospective study included 50 patients who had hip infections, of which 41 were periprosthetic joint infections, 3 were internal fixation infections, and 6 had septic arthritis. They were divided into two groups according to the spacer type: 23 patients treated with handmade spacers comprising 1 to 2 Kirschner wires as an endoskeleton (group A) and 27 patients treated with 1.5-stage FAHS comprising a cemented femoral stem, metal femoral head, and polyethylene acetabular liner or cemented acetabular cup (group B). Clinical characteristics, surgical data, infection control rate, spacer complications, modified Harris hip, visual analog scale, and 36-item short-form physical functioning scale scores were compared between the groups. All patients were followed up for at least 24 months after the last surgical procedure. RESULTS: No significant differences were noted in the infection eradication rate between the two groups (100 versus 96.30%, P = 1.0). The incidence of mechanical complications, especially spacer fracture, was significantly lower in group B than in group A (P = .044). Hip function and quality of life were significantly better in group B during the interim period. Group B patients had a longer interval time (median 7.40 versus 4.30 months, P = .004) and a lower reimplantation rate than group A patients (42.31 versus 82.61%, P = .004). CONCLUSIONS: The 1.5-stage FAHS surgical technique is feasible for the treatment of hip infection, with a lower mechanical complication rate, better hip function, and better quality of life during the interim period compared to that of handmade spacers. The 1.5-stage FAHS with maintained function could delay or negate the need for second-stage revision.

Trends in microbiological epidemiology of orthopedic infections: a large retrospective study from 2008 to 2021.

BACKGROUND: This study assessed the distribution characteristics of pathogens isolated from cases of orthopedic infections and focused on the antimicrobial susceptibility of the main pathogens. METHODS: This retrospective study involved patients with orthopedic infection in a tertiary medical center located in Shanghai, China, from 2008 to 2021.Pathogen information and the basic information of patients were identified from clinical microbiology laboratory data and the institutional medical record system. RESULTS: In total, the pathogen information of 2821 patients were enrolled in the study. S. aureus (37.71%) was the main causative pathogen responsible for orthopedic infection. Gender, pathogens distribution and polymicrobial infection rates were significantly different (P < 0.05) among patients with different orthopedic infection diseases.The trends in the distribution of pathogens in the total cohort, implant-related infection group (Group A), non-implant-related infection group (Group B), and the sub-group of cases with arthroplasty showed significant linear changes over time. And the polymicrobial infection rates of the total cohort (from 17.17% to 11.00%), Group B(from 24.35% to 14.47%), and the sub-group of cases with internal fixation (from 10.58% to 4.87%) decreased significantly. The antimicrobial susceptibility showed changing trends with time for some main pathogens, especially for S.aureus and Enterobacter spp. CONCLUSIONS: Our research indicated that the pathogen distribution and antimicrobial susceptibility in orthopedic infections changed over time. And the distribution of pathogens varied significantly among different types of orthopedic infectious diseases. These findings may serve as a reference for prophylaxis and empirical treatment strategies of orthopedic infection.

Macrophage-biomimetic porous Se@SiO2 nanocomposites for dual modal immunotherapy against inflammatory osteolysis.

BACKGROUND: Inflammatory osteolysis, a major complication of total joint replacement surgery, can cause prosthesis failure and necessitate revision surgery. Macrophages are key effector immune cells in inflammatory responses, but excessive M1-polarization of dysfunctional macrophages leads to the secretion of proinflammatory cytokines and severe loss of bone tissue. Here, we report the development of macrophage-biomimetic porous SiO2-coated ultrasmall Se particles (porous Se@SiO2 nanospheres) to manage inflammatory osteolysis. RESULTS: Macrophage membrane-coated porous Se@SiO2 nanospheres(M-Se@SiO2) attenuated lipopolysaccharide (LPS)-induced inflammatory osteolysis via a dual-immunomodulatory effect. As macrophage membrane decoys, these nanoparticles reduced endotoxin levels and neutralized proinflammatory cytokines. Moreover, the release of Se could induce macrophage polarization toward the anti-inflammatory M2-phenotype. These effects were mediated via the inhibition of p65, p38, and extracellular signal-regulated kinase (ERK) signaling. Additionally, the immune environment created by M-Se@SiO2 reduced the inhibition of osteogenic differentiation caused by proinflammation cytokines, as confirmed through in vitro and in vivo experiments. CONCLUSION: Our findings suggest that M-Se@SiO2 have an immunomodulatory role in LPS-induced inflammation and bone remodeling, which demonstrates that M-Se@SiO2 are a promising engineered nanoplatform for the treatment of osteolysis occurring after arthroplasty.

Reevaluating Current Cutoffs for Acute Periprosthetic Joint Infection: Current Thresholds Are Insensitive.

BACKGROUND: Diagnosing acute periprosthetic joint infection remains a challenge. Several studies have proposed different acute cutoffs resulting in the International Consensus Meeting recommending a cutoff of 100 mg/L, 10,000 cell/µL and 90% for serum C-reactive protein (CRP), synovial white blood cell count (WBC), and polymorphonuclear percentage (PMN%), respectively. However, establishing cutoffs are difficult as the control group is limited to rare early aseptic revisions, and performing aspiration in asymptomatic patients is difficult because of a fear of seeding a well-functioning joint arthroplasty. This study (1) assessed the sensitivity of current thresholds for acute periprosthetic joint infection (PJI) and (2) identified associated factors for false negatives. METHODS: We retrospectively reviewed patients with acute PJIs (n = 218), defined as less than 6 weeks from index arthroplasty, treated between 2000 and 2017. Diagnosis of PJI was based on 2 positive cultures of the same pathogen from the periprosthetic tissue or synovial fluid samples. Sensitivities of International Consensus Meeting cutoff values of CRP, synovial WBC, and PMN% were evaluated according to organism type. Multiple logistic regression analysis was performed to determine associated factors for false negatives. RESULTS: Overall, the sensitivity of CRP, synovial WBC, and PMN% for acute PJI was 55.3%, 59.6%, and 50.5%, respectively. Coagulase-negative Staphylococcus (CNS) demonstrated the lowest sensitivity for both CRP (37.5%) and WBC (55.6%). CNS infection was identified as an independent risk factor for false-negative CRP. CONCLUSIONS: Current thresholds for acute PJI may be missing approximately half of PJIs. Low virulent organisms, such as CNS, may be responsible for these false negatives. Current thresholds for acute PJI must be reexamined.

Two-Stage Exchange Arthroplasty for Periprosthetic Joint Infection: The Rate and Reason for the Attrition After the First Stage.

BACKGROUND: Two-stage exchange arthroplasty remains a popular surgical treatment for patients with chronic periprosthetic joint infection (PJI). Patients who do not receive reimplantation were largely overlooked in the current literature. We aimed at investigating the clinical outcomes of these patients. METHODS: Our institutional PJI database was retrospectively reviewed to identify 616 patients (237 hips, 379 knees) who were treated with an intended 2-stage exchange. Of them, 111 (18%) did not receive reimplantation within a minimum follow-up of 1 year. Chart review and targeted interviews were performed to elucidate the cause of attrition. Patients were considered to have failed treatment in the absence of reimplantation if they remained medically unfit for reimplantation, underwent a salvage procedure, or died during the study period. RESULTS: Of the 111 patients without reimplantation, 29 (26.1%) did well with their retained spacer and were unwilling to proceed with reimplantation, 23 (20.7%) underwent salvage procedures, and the remaining 59 (53.2%) were considered medically unfit for reimplantation, with 34 of them dying within 1 year of initial spacer insertion. The overall success rate for 2-stage exchange cohort at 2 years was 65.7% when treatment failure without reimplantation was taken into account. Several factors associated with increased risk of treatment failure without reimplantation were identified using a multivariate regression model. CONCLUSION: Almost 1 in 5 patients may never receive the intended reimplantation. Among many reasons for attrition, mortality appears to be a relatively common event. The current definition of treatment success does not take into account the attrition group and thus inflates the relative success of 2-stage exchange arthroplasty.

Longer Operative Time Results in a Higher Rate of Subsequent Periprosthetic Joint Infection in Patients Undergoing Primary Joint Arthroplasty.

BACKGROUND: Whether prolonged operative time is an independent risk factor for subsequent surgical site infection (SSI) and periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) remains a clinically significant and underexplored issue. The aim of this study is to investigate the association between operative time and the risk of subsequent SSI and PJI in patients undergoing primary TJA. METHODS: We retrospectively reviewed 17,342 primary unilateral total knee arthroplasty and total hip arthroplasty performed at a single institution between 2005 and 2016, with a minimum follow-up of 1 year. A multivariate logistic regression model was conducted to identify the association between operative time and the development of SSI within 90 days and PJI within 1 year. RESULTS: Overall, the incidence of 90-day SSI and 1-year PJI was 1.2% and 0.8%, respectively. Patients with an operative time of >90 minutes had a significantly higher incidence of SSI and PJI (2.1% and 1.4%, respectively) compared to cases lasting between 60 and 90 minutes (1.1% and 0.7%), and those lasting ≤60 minutes (0.9% and 0.7%, P < .01). In the multivariate model, the risk for infection increased by an odds ratio of 1.346 (95% confidential interval 1.114-1.627) for 90-day SSI and 1.253 (95% confidential interval 1.060-1.481) for 1-year PJI for each 20-minute increase in operative time. CONCLUSION: In patients undergoing primary TJA, each 20-minute increase in operative time was associated with nearly a 25% increased risk of subsequent PJI. We advocate that surgeons pay close attention to this underappreciated risk factor while maintaining safe operative practices, which minimize unnecessary steps and wasted time in the operating room.

The Presence of Sinus Tract Adversely Affects the Outcome of Treatment of Periprosthetic Joint Infections.

BACKGROUND: A sinus tract may be encountered in patients with periprosthetic joint infection (PJI) and constitutes a major criterion for diagnosis. The aim of this study is to identify associated factors for the presence of sinus tract and outcome of 2-stage exchange arthroplasty in these patients. METHODS: We retrospectively reviewed all patients with PJI following hip and knee arthroplasty from 2000 to 2017. Of them, 161 patients with a sinus tract had a minimum follow-up of 1 year following 2-stage exchange arthroplasty. These patients were matched 1:2 with those without sinus tract by using propensity score matching. Treatment success was assessed using the modified Delphi criteria. A multiple logistic regression analysis was performed to determine the effect of sinus tract on the outcome and associated factors for the presence of sinus tract. RESULTS: Factors significantly associated with sinus tract included smoking (odds ratio [OR] = 1.83), hypothyroidism (OR = 1.62), hypoalbuminemia (OR = 1.52), hip joint involvement (OR = 1.43), and prior revision surgery (OR = 1.37). Patients with sinus tract had a significantly higher rate of failure compared to those without sinus tract (OR = 2.94). CONCLUSION: This study demonstrates that the presence of sinus tract in patients with PJI adversely affects the outcome of treatment of these patients. The presence of sinus tract may be a proxy for other issues such as poor periarticular soft tissue, the poor nutritional status of the host, and multiple prior operations. These findings need to be borne in mind when treating patients with PJI and a concomitant sinus tract.

Surgical Treatment of Chronic Periprosthetic Joint Infection: Fate of Spacer Exchanges.

BACKGROUND: Patients with periprosthetic joint infection (PJI) undergoing 2-stage exchange arthroplasty may undergo an interim spacer exchange for a variety of reasons including mechanical failure of spacer or persistence of infection. The objective of this study is to understand the risk factors and outcomes of patients who undergo spacer exchange during the course of a planned 2-stage exchange arthroplasty. METHODS: Our institutional database was used to identify 533 patients who underwent a 2-stage exchange arthroplasty for PJI, including 90 patients with a spacer exchange, from 2000 to 2017. A retrospective review was performed to extract relevant clinical information. Treatment outcomes included (1) progression to reimplantation and (2) treatment success as defined by a Delphi-based criterion. Both univariate and multivariate Cox regression models were performed to investigate whether spacer exchange was associated with failure. Additionally, a propensity score analysis was performed based on a 1:2 match. RESULTS: A spacer exchange was required in 16.9%. Patients who underwent spacer exchanges had a higher body mass index (P < .001), rheumatoid arthritis (P = .018), and were more likely to have PJI caused by resistant (0.048) and polymicrobial organisms (P = .007). Patients undergoing a spacer exchange demonstrated lower survivorship and an increased risk of failure in the multivariate and propensity score matched analysis compared to patients who did not require a spacer exchange. DISCUSSION: Despite an additional load of local antibiotics and repeat debridement, patients who underwent a spacer exchange demonstrated poor outcomes, including failure to undergo reimplantation and twice the failure rate. The findings of this study may need to be borne in mind when managing patients who require spacer exchange.

Synergistic effects of intravenous and intra-articular tranexamic acid on reducing hemoglobin loss in revision total knee arthroplasty: a prospective, randomized, controlled study.

BACKGROUND: Tranexamic acid decreases blood loss in primary total knee arthroplasty, and no related prospective randomized clinical trials have been conducted to evaluate the effectiveness and safety of tranexamic acid in revision total knee arthroplasty. Thus, we conducted this work to evaluate the synergistic effects of intravenous plus intra-articular tranexamic acid on reducing hemoglobin loss compared with intra-articular tranexamic acid alone in revision total knee arthroplasty. STUDY DESIGN AND METHODS: This prospective, controlled study randomized 96 patients undergoing revision total knee arthroplasty into two groups: an intravenous plus intra-articular tranexamic acid group (48 patients who received 20 mg/kg intravenous tranexamic acid and 3.0 g intra-articular tranexamic acid); and an intra-articular tranexamic acid alone group (48 patients who received the same intravenous volume of normal saline and 3.0 g intra-articular tranexamic acid). The primary outcome was hemoglobin loss. Secondary outcomes included the volume of drain output, the percentage of patients who received transfusions, the number of units transfused, and thromboembolic events. RESULTS: The baseline data, preoperative hemoglobin, and tourniquet time were similar in both groups. There was significantly less hemoglobin loss in the intravenous plus intra-articular tranexamic acid group compared with the intra-articular tranexamic acid alone group (2.7 ± 0.6 g/dL and 3.7 ± 0.7 g/dL; p < 0.001). Compared with the intra-articular tranexamic acid alone group, the intravenous plus intra-articular tranexamic acid group also had significantly less drain output, fewer patients who received transfusions, and fewer units transfused (all p < 0.05). There were no significant differences in thromboembolic events in the two groups during the 3-month follow-up. CONCLUSION: Compared with intra-articular tranexamic acid alone, combined intravenous plus intra-articular tranexamic acid significantly reduced hemoglobin loss and the need for transfusion without an apparent increase in thromboembolic events in patients who underwent revision total knee arthroplasty.

A lithium-containing nanoporous coating on entangled titanium scaffold can enhance osseointegration through Wnt/ß-catenin pathway.

An entangled titanium wire porous (ETP) scaffold shows similar mechanical properties of cancellous bone and is a promising bone repair material. However, the ETP scaffold's inert biocompatibility and poor osteogenic ability limit its clinical application. In this study, a Li-containing nanoporous coating was added on ETP by micro-arc oxidation (MAO). The SEM results indicated that a hierarchical and compact coating was formed on the Li-MAO-ETP scaffold. In vitro cell tests showed improved osteoblast morphology, adhesion, and viability in the Li-MAO-ETP group. Moreover, the Li-MAO-ETP scaffold exhibited improved osteogenic differentiation properties by activating the Wnt/ß-catenin signal pathway based on the western blotting and RT-PCR results. The push-out test, sequential fluochrome labeling, and toluidine staining demonstrated that the Li-MAO-ETP scaffold contained improved osteogenic ability in vivo. The in vitro and in vivo experiments showed that the Li incorporated entangled porous titanium could be a suitable biomaterial for bone defect repair.

Comparable outcome of culture-negative and culture-positive periprosthetic hip joint infection for patients undergoing two-stage revision.

PURPOSE: Lack of peri-operative microbiological evidence is an unfavourable factor in one-stage revision. The objective of this study was to figure out whether being culture-negative was an unfavourable factor for periprosthetic hip joint infection (PHJI) in patients undergoing two-stage revision. METHODS: Records of PHJI patients treated between October 2003 and December 2016 were reviewed at our institution. Information such as microbiological data, clinical outcomes, and other details of patients' clinical courses were recorded. RESULTS: A total of the 58 cases were reviewed. The median follow-up duration was 68.5 months. The infection control rate of PHJI was 93.1% after two-stage revision. Kaplan-Meier analysis showed no significant difference in infection control rates between culture-negative and culture-positive groups. Culture-positive sinus secretions were significantly associated with an increased rate of reinfection (P = 0.039). CONCLUSIONS: Two-stage revision had a high success rate for eradication of PHJI. Culture-negative PHJI had a comparable outcome with culture-positive PHJI.

Comparison of 3 Routes of Administration of Tranexamic Acid on Primary Unilateral Total Knee Arthroplasty: A Prospective, Randomized, Controlled Study.

BACKGROUND: The mode of administration for tranexamic acid (TXA) to significantly reduce the decrease in hemoglobin (Hb), number of transfusions, relevant costs, and side effects in patients undergoing primary unilateral total knee arthroplasty (TKA) has not been resolved. METHODS: A total of 560 patients undergoing primary unilateral TKA were randomized into 4 groups: intravenous group (140 patients receiving 2 doses of 20 mg/kg intravenous TXA), topical group (140 patients administered 3.0 g topical TXA), oral group (140 patients given 2 doses of 20 mg/kg oral TXA), and a control group (140 patients not given TXA). The primary outcomes included postoperative 48-hour Hb loss and drainage volume, number of transfusions, transfusion and TXA costs, and thromboembolic complications. Secondary outcomes were postoperative inpatient time and wound healing 3 weeks after TKA. RESULTS: Baseline data among the 4 groups were similar. The 48-hour Hb loss and drainage volume in the intravenous, topical, and oral groups were significantly less (P < .05) than those in the control group, and the latter had significantly more transfusions and transfusion costs than the other 3 groups (P < .05). The TXA cost was lowest in the oral group compared with that in the topical and intravenous groups (P < .05). No differences in thromboembolic complications, postoperative inpatient time, or wound healing were observed among the groups. However, wound dehiscence and continuous wound discharge occurred in the topical group. CONCLUSION: All the 3 modes of TXA administration significantly reduced postoperative Hb loss, the number of transfusions, and transfusion costs compared with those in the control group. No pulmonary embolism or infection was observed. Oral TXA is recommended because it provided a similar clinical benefit and resulted in the lowest TXA cost compared with the other 2 modes of TXA administration.

Intra-articular Application is More Effective Than Intravenous Application of Tranexamic Acid in Total Knee Arthroplasty: A Prospective Randomized Controlled Trial.

BACKGROUND: The optimal administration route of tranexamic acid (TXA) in total knee arthroplasty (TKA), and the effect of TXA on hidden blood loss and total blood loss are undetermined. The purpose of this study was to compare the effectiveness of intravenous versus intra-articular application of tranexamic acid in patients undergoing knee arthroplasty. METHODS: A total of 150 patients undergoing primary unilateral total knee arthroplasty were randomly distributed to 3 groups (IV, intra-articular, and control group; each 50 patients) and administrated TXA (1 g IV and 50 mL intra-articular saline, 1 g intra-articularly and 50 mL intra-articular saline, and 0 g and 50 mL intra-articular saline, respectively). The amount of total and hidden blood loss (HBL), drainage, transfusion, changes in hemoglobin levels, and complications were recorded. RESULTS: Intra-articular use of TXA reduced more total blood loss (P = .011) and reduced more total 48 hours drainage volume than IV use of TXA (P < .001). Two patients received transfusion in IV and control group. No deep venous thrombosis or other severe complications had occurred. The HBL volume had no significant difference among the control, IV, and intra-articular groups (708.6 ± 308.2, 651.7 ± 302.9, and 625.2 ± 252.1 mL, respectively; which was 65.6%, 70.8%, and 81.1% of the total loss). CONCLUSION: Intra-articular administration of TXA significantly reduced total blood loss and drainage volume to a greater degree than IV injection in total knee arthroplasty without reduction of HBL.

Sonication of explanted prosthesis combined with incubation in BD bactec bottles for pathogen-based diagnosis of prosthetic joint infection.

Prosthetic joint infection (PJI) is a rare but refractory complication of arthroplasty. Accurate identification of pathogens is a key step for successful treatment of PJI, which remains a challenge for clinicians and laboratory workers. We designed a combined culture method with sonication of implants and incubation in a BD Bactec system to improve the effectiveness of pathogen diagnosis in PJI. The aims of this study were to investigate the diagnostic accuracy of sonicate fluid cultures in the BD Bactec system and to compare the results with those of synovial fluid cultures in the BD Bactec system. The prosthetic components removed were sonicated in Ringer's solution, and then sonicate fluid was incubated in Bactec bottles for 5 days. Synovial fluid was incubated in Bactec bottles for 5 days as a control. Synovial fluid cultures with Bactec bottles and sonicate fluid cultures with Bactec bottles showed sensitivities of 64% and 88%, respectively (P = 0.009), with specificities of 98% and 87% (P = 0.032), respectively. Sonicate fluid cultures with Bactec bottles were more sensitive than synovial fluid cultures with Bactec bottles regardless of whether antimicrobial agents were used within 14 days before surgery (81% versus 52%; P = 0.031) or not (93% versus 72%; P = 0.031). Sonication of explanted prostheses followed by incubation of the resulting sonicate fluid in Bactec bottles detected many more pathogens than did synovial fluid cultures with Bactec bottles. This method is also effective in cases with antibiotic treatment before surgery.

Effect of Posterior Cruciate Ligament Resection on Gap Balancing in Robot-assisted Total Knee Arthroplasty.

OBJECTIVE: Retention or sacrifice of the posterior cruciate ligament (PCL) is one of the most controversial issues while performing total knee arthroplasty (TKA). This study aimed to evaluate the impact of PCL resection on flexion-extension gaps, femoral component rotation, and bone resection amounts during robot-assisted TKA. METHODS: This prospective study included 40 patients with knee osteoarthritis who underwent robot-assisted posterior-stabilized (PS) TKA between September 2021 and February 2022. Of the patients, 75% were women (30/40) with a mean age and BMI of 72.6 years and 27.4 kg/m2, respectively. The guidance module and camera stand assembly were used to capture gaps before and after PCL resection. Measurements of femoral component rotation and bone resection amounts were made in cruciate-retaining (CR) TKA mode and PS-TKA mode. RESULTS: After PCL resection, the mean change in the medial and lateral compartments of flexion gaps increased by 2.0 and 0.6 mm, respectively (p < 0.001). Compared with the CR-TKA mode group, the bone resection amounts of the medial posterior condyle and the lateral posterior condyle in the PS-TKA mode group decreased by 2.0 ± 1.1 and 1.1 ± 1.1 mm, respectively, and the external rotation of the femoral prosthesis relative to the posterior condylar axis and trans-epicondylar line was reduced by 1.0° ± 1.3° and 1.2° ± 1.6°, respectively (p < 0.001). CONCLUSION: The release of the PCL did not affect the extension gap, but significantly increased the flexion gap. Moreover, the increases in the medial flexion gap were greater than those of the lateral flexion gap. After PCL resection, less external rotation of the femoral prosthesis and fewer bone cuts of the posterior femur were needed in PS-TKA.

Diagnostic Role of Metagenomic Next-Generation Sequencing in Tubercular Orthopedic Implant-Associated Infection.

Objective: The diagnosis of tubercular orthopedic implant-associated infection (TB-IAI) is challenging. This study evaluated the value of metagenomic next-generation sequencing (mNGS) for the diagnosis of TB-IAI and developed a standardized diagnostic procedure for TB-IAI. Methods: The records of all patients with TB-IAI diagnosed and treated at our institution between December 2018 and September 2022 were retrospectively reviewed. Patient demographic characteristics, medical history, laboratory test, microbial culture, histopathology, and mNGS results, and time to diagnosis were recorded. The diagnostic efficiency of mNGS for TB-IAI was assessed by comparing the results and diagnostic time with that of other diagnostic modalities. Results: Ten patients were included in the analysis, including eight with prosthetic joint infections and two with fracture-related infections. The mNGS positivity rate was 100% (10/10), which was higher than that of TB-antibody (11%, 1/9), real-time quantitative polymerase chain reaction (22%, 2/9), T-SPOT.TB (25%, 2/8), purified protein derivative (50%, 4/8), microbial culture (50%, 5/10), and histopathology (20%, 2/10). mNGS shortened the time to diagnosis of TB-IAI. A standardized diagnostic procedure for TB-IAI was developed based on the findings. Conclusion: mNGS is useful for the diagnosis of TB-IAI. mNGS is recommended in cases where it is difficult to identify a pathogen using routine diagnostic tests. The standardized diagnostic procedure might improve TB-IAI diagnosis. Importance: TB-IAI is a rare infection, which occurs after orthopedic surgery and hard to diagnose microbiologically. mNGS is a new detection technique not yet discussed in current literature as a means for TB-IAI diagnostics. Here we describe a cohort of patients with TB-IAI diagnosed by mNGS show high efficiency of mNGS for detection of this pathology and present a clinical algorithm supplementing conventional methods for TB-IAI assessment.