original article
Diagnostic performance of bone histopathology in fracture-related infection at a specialized hospital in Uruguay
Rendimiento diagnóstico de la histopatología ósea en la infección relacionada con fracturas en un hospital especializado en Uruguay
Karina Tenaglia¹
Pedro Catalurda2 Andrea Cristiani³ Agustín Villalba² Alejandro Azziz² Julio Medina¹
1 Universidad de la República, Faculty of Medicine, Academic Unit of Infectous Diseases, Montevideo, Uruguay.
² National Institute of Orthopedics and Traumatology, Montevideo, Uruguay.
³ Universidad de la República, Faculty of Medicine, Department of Pathology, Montevideo, Uruguay.
Open access
Received: 02/10/2025
Accepted: 21/05/2026
Correspondence: Karina Tenaglia, National Institute of Orthopedics and Traumatology, Infectious Diseases Unit, Faculty of Medicine, Universidad de la República, Montevideo, Uruguay. Email: ktenaglia2007@gmail.com.
How to cite: Tenaglia K, Catalurda P, Cristiani A, Villalba A, Azziz A, Medina J. Diagnostic performance of bone histopathology in fracture-related infection at a specialized hospital in Uruguay. Rev. colomb. Ortop. Traumatol. 2026; 40: e657. https://doi.org/10.58814/01208845.657
Cómo citar: Tenaglia K, Catalurda P, Cristiani A, Villalba A, Azziz A, Medina J. [Rendimiento diagnóstico de la histopatología ósea en la infección relacionada con fracturas en un hospital especializado en Uruguay]. Rev. colomb. Ortop. Traumatol. 2026; 40: e657. https://doi.org/10.58814/01208845.657
Copyright: ©2026 The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, as long as the original author and source are credited.
Abstract
Introduction: Fracture Related infections (FRI) are among the most complex complications in orthopedic trauma, with significant functional and economic impact. The AO/EBJIS 2018 consensus established standardized diagnostic criteria including bone histopathology as a confirmatory criterion; however, its performance has been scarcely evaluated in Latin America.
Objectives: To characterize FRI in a national referral center and evaluate the diagnostic performance of bone histopathology compared with intraoperative culture.
Methodology: A prospective observational study was conducted between January 1, 2021 and February 29, 2024 at the National Institute of Orthopedics and Traumatology (Montevideo, Uruguay). Adults (≥18 years) with suspected or confirmed FRI undergoing surgery with deep tissue sampling for microbiological culture and histopathology were included. Each patient was included once. Vertebral fractures, prosthetic joint infections, superficial samples, and cases without analyzable samples were excluded. AO/EBJIS 2018 criteria were applied. Histopathological performance was evaluated using culture as reference, calculating sensitivity, specificity, predictive values, and 95% confidence intervals.
Results: A total of 67 patients were analyzed (mean age 43 ± 17.80 years; 73.13% male). Predisposing factors were present in 73.13%, open fractures in 52.24%, and lower limb involvement in 94.03%. Positive cultures were obtained in 77.61% (52/67), with polymicrobial infections in 36.54%. The most frequent pathogens were Staphylococcus aureus (36.49%), Enterococcus spp. (9.46%), and Gram-negative bacilli (27%); 18.75% of Staphylococcus spp. were methicillin-resistant and 44.44% of Enterobacterales isolates were multidrug-resistant. Histopathology was positive in 65.67% (44/67), with sensitivity 73.08%, specificity 60%, PPV 86.36%, and NPV 39.13%. In non-union (n=31), sensitivity was 80% and PPV 76.19%.
Conclusions: Fracture-related infections are associated with high-energy trauma and a high proportion of multidrug-resistant organisms. Bone histopathology is a complementary diagnostic tool to culture, with greater confirmatory than exclusion value, particularly in non-union.
Keywords: Fractures; Fracture Fixation; Surgical Wound Infection; Histology; Diagnosis; Bone Diseases, Infectious (MeSH).
Resumen
Introducción: las infecciones relacionadas a fracturas (IRF) constituyen una de las complicaciones más complejas en la traumatología ortopédica, con alto impacto funcional y económico. El consenso internacional AO/EBJIS 2018 estableció criterios diagnósticos estandarizados que incluyen la histopatología ósea como criterio confirmatorio, aunque su rendimiento ha sido poco evaluado en América Latina.
Objetivos: caracterizar las IRF en un centro de referencia nacional y evaluar el rendimiento diagnóstico de la histopatología ósea en comparación con el cultivo intraoperatorio.
Metodología: estudio observacional prospectivo realizado entre el 1 de enero de 2021 y el 29 de febrero de 2024 en el Instituto Nacional de Ortopedia y Traumatología (Montevideo, Uruguay). Se incluyeron pacientes ≥18 años con sospecha o diagnóstico confirmado de IRF sometidos a cirugía con obtención de muestras profundas para cultivo microbiológico e histopatología ósea. Cada paciente fue incluido una sola vez. Se excluyeron fracturas vertebrales, infecciones protésicas, muestras superficiales y ausencia de muestras analizables. Se aplicaron los criterios AO/EBJIS 2018. El rendimiento de la histopatología se evaluó tomando el cultivo como estándar de referencia, calculando sensibilidad, especificidad, valores predictivos e IC95%.
Resultados: se analizaron 67 pacientes (edad media 43 ± 17,8 años; 73,13% varones). El 73,13% presentó factores predisponentes, el 52,24% fracturas expuestas y el 94,03% afectación de miembros inferiores. Se obtuvo aislamiento microbiológico en 77,61% (52/67), con infecciones polimicrobianas en 36,54%. Los microorganismos más frecuentes fueron Staphylococcus aureus (36,49%), Enterococcus spp. (9,46%) y bacilos Gram negativos (27%); el 18,75% de Staphylococcus spp. fueron resistentes a meticilina y el 44,44% de las Enterobacterales fueron multirresistentes. La histopatología fue positiva en 65,67% (44/67), con sensibilidad 73,08%, especificidad 60%, VPP 86,36% y VPN 39,13%. En pseudoartrosis (n=31), la sensibilidad fue 80% y el VPP 76,19%.
Conclusiones: las infecciones relacionadas a fracturas se asocian a traumatismos de alta energía y a una elevada proporción de microorganismos multirresistentes. La histopatología ósea constituye una herramienta diagnóstica complementaria al cultivo, con mayor valor confirmatorio que de exclusión, especialmente en pseudoartrosis.
Palabras clave: Fracturas; Fijación Interna de Fracturas; Infección de la Herida Quirúrgica; Histología; Diagnóstico Clínico; Enfermedades Óseas Infecciosas (DeCS).
Introduction
Fracture Related Infections (FRI) constitute a serious complication of traumatic bone injuries. The current definition was standardized by the international AO/EBJIS consensus, which establishes confirmatory and suggestive criteria integrating clinical, microbiological, and histopathological findings.1,2 These criteria have been validated, demonstrating adequate diagnostic performance in clinical practice.3
The incidence of FRI varies according to fracture type, with approximate rates of 1–2% in closed fractures and up to 25–30% in high-energy open fractures.4 Its clinical impact is considerable, as its management typically requires multiple surgical procedures, prolonged antibiotic therapy, and extensive hospitalizations.4 In addition, this scenario is associated with significant deterioration in quality of life and with long-term sequelae.5,6
Various risk factors have been associated with the development of FRI, including prior use of systemic antibiotics and immunosuppression.7 In certain contexts, such as high-energy trauma, the infection may present particular microbiological characteristics, resulting in greater complexity of management.8
In Latin America, available data on fracture-related infections are scarce and heterogeneous. In Uruguay, no national estimates exist; however, in a study conducted at a referral center, FRI accounted for approximately half of the osteoarticular infections treated.9
The diagnosis of FRI remains a challenge and requires a multimodal approach.2 International recommendations emphasize obtaining multiple deep-tissue samples and warn about the limitations of serum biomarkers in the context of recent trauma.10,11 In this regard, the proposed diagnostic criteria have proven to be useful for standardizing clinical evaluation.12
Among the diagnostic tools, bone histopathology has gained relevance as a complement to microbiological study.11,12 The combination of cultures and histology allows improvement in diagnostic accuracy compared with the isolated use of each technique.11 The heterogeneous distribution of the infectious process in bone tissue supports the need for an adequate sampling strategy.13 In specific situations, intraoperative histological analysis may provide additional diagnostic information.14
The presence of polymorphonuclear infiltrate in bone tissue constitutes a key criterion for the histopathological diagnosis of infection.15 Likewise, obtaining multiple deep-tissue samples is essential to optimize microbiological yield and to differentiate contamination from true infection.12
In this context, the objectives of this study were to characterize fracture-related infections at a national referral center and to evaluate the diagnostic performance of bone histopathology compared with intraoperative culture.
Methodology
Study type, population, and sample
The present study is a prospective observational cohort study. Adult patients (≥18 years) with suspected or confirmed diagnosis of FRI, treated between January 1, 2021, and February 29, 2024, at the National Institute of Orthopedics and Traumatology, Montevideo, Uruguay, were included. Sixty-seven patients were included. Each patient was included only once, regardless of the number of readmissions or interventions related to the same infection during the study period.
Inclusion criteria
Adult patients (≥18 years) with suspected or confirmed diagnosis of FRI in whom deep samples were obtained for microbiological culture and histopathological study, via open surgical procedure or percutaneous biopsy.
Exclusion criteria
Patients with vertebral fracture infections, infections associated with joint prostheses implanted in the context of a fracture, samples obtained during the first debridement of open fractures, and patients without samples available for microbiological or histopathological analysis were excluded.
Study variables
The diagnosis of FRI was established according to the criteria of the AO/EBJIS 2018 international consensus.1,2 Confirmatory criteria considered were: the presence of a bone or implant-related fistula, intraoperative pus, the isolation of the same microorganism in at least two deep samples, and compatible histopathological findings, defined as the presence of >5 polymorphonuclear cells (PMNs) per high-power field in samples that included bone trabeculae.1,15
The suggestive criteria included clinical, radiological, or microbiological findings compatible with infection, without confirmatory criteria.1 For open fractures, the Gustilo-Anderson classification was used.16 The non-union was defined as absence of consolidation at 9 months or lack of radiological progression over 3 consecutive months.17
Procedure
Only samples obtained in the operating room (open surgery or biopsy) were analyzed, excluding superficial samples. In patients with open fractures, cultures were obtained starting from the second surgical debridement. The sampling was performed after the debridement of necrotic tissue. The number of samples obtained per patient was not standardized, being left to the discretion of the treating surgical team, based on the characteristics of each case. Nonetheless, priority was given to obtaining multiple deep-tissue samples, in accordance with international recommendations.
The microbiological samples were processed in the institution’s microbiology laboratory according to standardized protocols, and results were obtained from the institutional information system (Plexus).
Histopathological samples were periodically sent to the Pathology Department of the Hospital de Clínicas for processing, carried out by the same team of pathologists throughout the whole study period. Processing included formalin fixation, 5 μm sections, and staining with hematoxylin-eosin, Giemsa, Gram, PAS, and Grocott. Two levels were analyzed with hematoxylin-eosin, and additional sections were prepared for special stains.
Analysis was performed without prior knowledge of the clinical situation or paraclinical results. The entirety of the tissue represented in the histological sections was evaluated, with a minimum of 100 high-power fields per sample, in accordance with the department’s methodology. Polymorphonuclear cell counts were performed using light microscopy.
Data collected
Demographic variables were recorded, and systemic risk factors (diabetes mellitus, immunosuppression) and local risk factors (smoking) were considered, as documented in the medical record. Additionally, clinical characteristics, inflammatory biomarkers, microbiological and histopathological results, surgical procedures, antimicrobial treatment, and clinical evolution were also collected.
Statistical analysis
Data were analyzed using Stata version 15.0 (StataCorp, College Station, TX, USA). The continuous variables were expressed as mean and standard deviation or median and interquartile range, according to their distribution, and categorical variables as frequencies and percentages.
The comparison of the continuous variables between groups was performed using Student’s t-test or the Mann–Whitney test, and categorical variables using chi-square or Fisher’s exact test, as appropriate.
The diagnostic performance of histopathology was evaluated using microbiological culture as the reference standard, by calculating sensitivity, specificity, positive predictive value, and negative predictive value, with 95% confidence intervals. Statistical significance was set at p<0.05.
Ethical Considerations
The study was approved by the Ethics Committee of the Faculty of Medicine (File No. 070153-000718-20, 12/2020) and was conducted in accordance with the principles of the Declaration of Helsinki,18 ensuring data confidentiality. The ethics committee authorized the use of clinical information for research purposes, without requiring individual informed consent.
Results
Sixty-seven patients diagnosed with fracture-related infection (FRI) were included. Epidemiological characteristics are presented in Table 1. Mean age was 43 ± 17.80 years, and 73.13% (n=49) were male. The median hospital stay was 22 days (IQR: 12–34).
A total of 73.13% (n=49) presented at least one risk factor for FRI, with smoking being the most frequent (79.59%; n=39). Open fractures accounted for 52.24% (n=35), and the predominant trauma mechanism was road traffic accidents (49.25%; n=33). The most frequent location was the lower limbs (94.03%; n=63).
Table 1. Baseline characteristics of the population (n=67).
|
Characteristic |
n (%) |
|---|---|
|
Age (years)* |
43 ± 17.80 |
|
Male sex |
49 (73.13) |
|
Hospital stay (days)** |
22 (12-34) |
|
Infection risk factors (n=49) |
|
|
Diabetes mellitus |
9 (18.37) |
|
Smoking |
39 (79.59) |
|
Immunosuppression |
4 (8.16) |
|
Fracture characteristics |
|
|
Lower limb |
63 (94.03) |
|
Open fracture |
35 (52.24) |
|
Mechanism of injury |
|
|
Road traffic accident |
33 (49.25) |
|
Other causes (including firearms and other mechanisms) |
34 (50.75) |
*Mean ± SD.**Median (IQR).
Source: Own elaboration.
Fracture and infection characteristics, clinical and paraclinical presentation
A total of 80.59% (54/67) of infections corresponded to chronic forms, predominantly affecting the tibia and femur.
The most frequent signs and symptoms were local inflammatory signs in 59.70% (n=40), pain in 47.76% (n=32), and fistula in 34.33% (n=23). Fever and other symptoms occurred in 20.90% (n=14). A total of 65.67% (n=44) presented two or more concomitant clinical manifestations.
C-reactive protein values were available for 66 patients on admission and 51 at hospital discharge.
On admission, 51.52% of patients presented values <50 mg/L, 28.79% had values between 50–200 mg/L, and 12.12% had values >200 mg/L, with 7.58% missing data. At discharge, values <50 mg/L predominated (70.59%), with a proportional decrease in values between 50–200 mg/L (13.73%) and >200 mg/L (5.88%), and 9.80% missing data (Table 2).
Table 2. Evolution of the C-reactive protein levels at admission and discharge in patients with fracture-related infection.
|
CRP (mg/L) |
Hospital admission n=66 (%) |
Hospital discharge n=51 (%) |
|
<50 |
34 (51.52) |
36 (70.59) |
|
50–200 |
19 (28.79) |
7 (13.73) |
|
> 200 |
8 (12.12) |
3 (5.88) |
|
Data not available |
5 (7.58) |
5 (9.80) |
Note: Percentages were calculated based on the number of patients at each time point. “Data not available” corresponds to absence of CRP recording at the time of discharge.Source: own elaboration.
Radiographic studies were available for all patients (n=67). A total of 44.78% (n=30) presented non-united fracture with bone lysis and/or implant loosening, 19.40% (n=13) presented acute nonunited fracture, 16.42% (n=11) showed bone consolidation, and 19.40% (n=13) presented other findings, including bone defect, non-union, or geodes.
Diagnosis of infection
94.03% (63/67) presented at least one major diagnostic criterion, and 95.52% (64/67) presented at least one minor criterion.
Among the 63 patients with at least one major criterion, the most frequent pattern was positive microbiological culture as the sole major criterion (26.98%; n=17), followed by the combination of pathology and microbiological culture (23.80%; n=15), and the association of fistula with microbiological culture (20.63%; n=13). Other patterns included fistula as the sole major criterion (9.52%; n=6), pathology as the sole major criterion (7.93%; n=5), the combination of fistula, pathology, and microbiological culture (9.52%; n=6), and fistula associated with pathology (1.58%; n=1).
Regarding suggestive (minor) criteria, 95.52% (64/67) presented at least one. Considering the coexistence of these criteria and assigning each patient a single combination, different patterns were identified, whose distribution is detailed in Table 3.
Table 3. Suggestive (minor) criteria for fracture-related infection according to the AO/EBJIS consensus present in the cohort (n=64).
|
Suggestive criteria |
n(%) |
|
1 positive culture |
1 (1.56) |
|
Non-union |
19 (29.69) |
|
Local inflammatory signs |
29 (45.31) |
|
Local inflammatory signs + joint effusion |
7 (10.94) |
|
Local inflammatory signs + non-union |
8 (12.50) |
Source: own elaboration.
Microbiological isolation was obtained in 77.61% (52/67) of patients; of these, 36.54% (19/52) corresponded to polymicrobial infections. Seventy-four microorganisms were identified (Table 4).
Table 4. Distribution of microorganisms isolated in fracture-related infections (n=74).
|
Microorganism |
n(%) |
|---|---|
|
Staphylococcus aureus |
27 (36.49) |
|
Enterococcus spp. |
7 (9.46) |
|
Streptococcus spp. |
6 (8.11) |
|
Enterobacter spp. |
7 (9.46) |
|
Coagulase-negative Staphylococcus |
5 (6.76) |
|
Bacillus spp. and other Gram-positives |
5 (6.76) |
|
Pseudomonas aeruginosa |
6 (8.11) |
|
Escherichia coli |
5 (6.76) |
|
Klebsiella pneumoniae, Proteus spp and Citrobacter spp. |
6 (8.10) |
Source: own elaboration.
Among Staphylococcus spp. isolates (n=32), 18.75% (n=6) were methicillin-resistant. Among Enterobacterales (n=18), 44.44% (n=8) presented multidrug resistance, and among non-fermenting Gram-negative bacilli (n=7), 28.57% (n=2) presented multidrug resistance.
Pathology
A total of 65.67% (44/67) of bone biopsies were positive for infection. Using microbiological culture as the reference, pathology showed a sensitivity of 73.08% (95% CI: 59.80–83.20), a specificity of 60% (95% CI: 35.80–80.20), a positive predictive value of 86.36% (95% CI: 73.30–93.60), and a negative predictive value of 39.13% (95% CI: 22.20–59.20) (Table 5).
Table 5. Diagnostic performance of pathology compared with microbiological culture.
|
Culture Positive |
Culture Negative |
Total |
|
|
Positive pathological anatomy |
38 |
6 |
44 |
|
Negative pathological anatomy |
14 |
9 |
23 |
|
Total |
52 |
15 |
67 |
Source: own elaboration.
Non-union
In patients with non-union (46.27%; 31/67), pathology showed a sensitivity of 80% (95% CI: 60.00–92.30), a specificity of 54.55% (95% CI: 28.00–78.70), a positive predictive value (PPV) of 76.19% (95% CI: 56.70–89.90), and a negative predictive value (NPV) of 60% (95% CI: 31.30–83.20) (Table 6).
Table 6. Diagnostic performance of pathology compared with microbiological culture.
|
Positive culture |
Negative culture |
Total |
|
|
Positive pathological anatomy |
16 |
5 |
21 |
|
Negative pathological anatomy |
4 |
6 |
10 |
|
Total |
20 |
11 |
31 |
Source: own elaboration.
Treatment
97.01% (65/67) of patients received medical-surgical treatment. Among patients with open fractures (n=35), 68.57% (24/35) required a single surgical debridement and 31.43% (11/35) required two or more.
Osteosynthesis material was removed in 50% (25/50) of patients who had it in place.
All patients received antimicrobial treatment; 88.06% (59/67) did so via dual-antibiotic regimens. The most commonly used parenteral antibiotics were trimethoprim-sulfamethoxazole, amikacin, cefazolin, vancomycin, and meropenem. Orally, trimethoprim-sulfamethoxazole, doxycycline, and cephalexin were mainly used. The median duration of intravenous treatment was 14 days (IQR: 8–20).
Discussion
In this cohort of patients with fracture-related infection (FRI), bone histopathology served as a complementary diagnostic tool, with greater capacity to confirm infection than to exclude it, consistent with the observed sensitivity (73.08%) and positive predictive value (86.36%), as well as with a low negative predictive value (39.13%). This behavior was more evident in the subgroup of patients with non-union, where diagnostic performance was higher.
The cohort was characterized by a predominance of young patients, with lower-limb involvement and a high proportion of chronic infections, in line with what has been described in contemporary FRI series.4,5
Clinically, male sex predominated, with a high frequency of predisposing factors, notably smoking and diabetes mellitus, consistent with previous studies.7,19
Likewise, FRI has been linked to high-energy trauma, open fractures, and predominant lower-limb involvement, which is reflected in this case series, where road traffic accidents were the main injury mechanism and more than half of the cases corresponded to open fractures.4,5,20
Regarding location, a clear predominance of lower-limb involvement was observed, with the tibia as the most frequently affected bone. This finding is consistent with what has been described in the international literature, where tibial fractures carry higher infection risk due to their limited soft-tissue coverage and greater exposure in high-energy trauma.4,5 Clinically, presentation was dominated by local inflammatory signs and pain, with a significant proportion of patients presenting active fistula and frequent coexistence of multiple clinical manifestations, reflecting the complexity of FRI in clinical practice.20
In the present study, systematic application of the AO/EBJIS 2018 international consensus diagnostic criteria allowed standardized identification of FRI.1 Most cases were confirmed by microbiological culture, although the presence of fistula and histopathological findings also contributed to diagnosis. These results reinforce the utility of a diagnostic approach based on defined criteria, facilitating comparability between studies and its application in clinical practice.1
The diagnostic performance of pathology demonstrated its role as a complementary tool in FRI, with greater confirmatory than exclusionary capacity. In the series studied, histopathological positivity was 65.67%, with a sensitivity of 73.08% and a positive predictive value of 86.36% using culture as the reference standard. In the non-union subgroup, performance was higher, suggesting a particularly relevant role in chronic or prolonged-course forms. These findings are consistent with previous studies that have demonstrated a high confirmatory value of bone histology.15 In this regard, the polymorphonuclear infiltrate cutoff significantly influences diagnostic specificity, reaching high values when strict thresholds are used.15 Consistently, greater inflammatory infiltrate is associated with a high positive predictive value for infection.15 In this context, the results reinforce the role of pathology as a complementary diagnostic tool, which should be interpreted together with clinical and microbiological findings.11,12 It should also be considered that microbiological culture, used as the reference standard, has limitations in sensitivity, especially in patients previously exposed to antimicrobials.12
From a microbiological standpoint, Staphylococcus aureus predominated in the present cohort, followed by Enterococcus spp. and Gram-negative bacilli. This pattern coincides with what has been described in the literature, where Gram-positive cocci are the most frequent organisms in FRI, although with a significant contribution from Gram-negative bacilli, especially in the context of open fractures and high-energy trauma.21,22 The proportion of polymicrobial infections observed reinforces the microbiological complexity of these infections, likely related to initial trauma contamination and to the need for repeated surgical procedures.20
A notable finding was the high proportion of antimicrobial resistance, both among Gram-positive cocci and Gram-negative bacilli. The presence of methicillin-resistant Staphylococcus spp. and multidrug-resistant Enterobacterales poses significant therapeutic challenges, limiting antimicrobial options with adequate bone penetration and safety for prolonged treatment. This issue is particularly relevant for multidrug-resistant Gram-negative bacilli, where therapeutic alternatives, especially oral ones, are limited. In this context, the findings are consistent with those reported in the international literature.21,23
Regarding treatment, most patients required medical-surgical management, with a need for debridement and, in a significant proportion, removal of osteosynthesis hardware, in accordance with current principles of FRI management.20,24 The antimicrobial strategy combined intravenous and oral antibiotics, with trimethoprim-sulfamethoxazole, doxycycline, and cephalexin being the most commonly used orally, in relation to their adequate bioavailability and bone-penetration profile.25-28
Among the strengths of the study are its prospective design, the systematic integration of microbiology and histopathology, and the application of international diagnostic criteria. As limitations, its single-center nature and sample size are recognized, which may restrict the generalizability of results, particularly in subgroup analyses.
Taken together, the results suggest that bone histopathology constitutes a valuable complementary diagnostic tool in FRI, with greater confirmatory than exclusionary capacity, which should be interpreted together with clinical and microbiological findings, supporting its integration within a diagnostic approach based on standardized criteria.1,2
Conclusions
FRI predominantly affect young adults in the context of high-energy trauma, with main involvement of the lower limbs and a high proportion of chronic infections. From a microbiological standpoint, they are characterized by the predominance of Staphylococcus aureus and a significant proportion of multidrug-resistant organisms.
Bone histopathology constitutes a diagnostic tool complementary to microbiological culture, with greater confirmatory than exclusionary value, particularly in patients with non-union. Its integration within a diagnostic approach based on international criteria contributes to improving diagnostic accuracy in FRI.
Conflicts of Interest
None reported by the authors.
Funding
None reported by the authors.
Acknowledgments
None reported by the authors.
Use of Artificial Intelligence
The authors declare having used artificial intelligence tools (ChatGPT, OpenAI) to support the drafting and editing of the manuscript. The scientific content, analysis, and interpretation of the data are the sole responsibility of the authors.
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