Aberrant Expression of SLC7A11 Impairs the Antimicrobial Activities of Macrophages in Staphylococcus Aureus Osteomyelitis in Mice.

Staphylococcus aureus (S. aureus) persistence in macrophages, potentially a reservoir for recurrence of chronic osteomyelitis, contributes to resistance and failure in treatment. As the mechanisms underlying survival of S. aureus in macrophages remain largely unknown, there has been no treatment approved. Here, in a mouse model of S. aureus osteomyelitis, we identified significantly up-regulated expression of SLC7A11 in both transcriptomes and translatomes of CD11b+F4/80+ macrophages, and validated a predominant distribution of SLC7A11 in F4/80+ cells around the S. aureus abscess. Importantly, pharmacological inhibition or genetic knockout of SLC7A11 promoted the bactericidal function of macrophages, reduced bacterial burden in the bone and improved bone structure in mice with S. aureus osteomyelitis. Mechanistically, aberrantly expressed SLC7A11 down-regulated the level of intracellular ROS and reduced lipid peroxidation, contributing to the impaired bactericidal function of macrophages. Interestingly, blocking SLC7A11 further activated expression of PD-L1 via the ROS-NF-κB axis, and a combination therapy of targeting both SLC7A11 and PD-L1 significantly enhanced the efficacy of clearing S. aureus in vitro and in vivo. Our findings suggest that targeting both SLC7A11 and PD-L1 is a promising therapeutic approach to reprogram the bactericidal function of macrophages and promote bacterial clearance in S. aureus osteomyelitis.

Cat-scratch disease: a rare cause of osteomyelitis.

Cat-scratch disease is a zoonosis caused by Bartonella henselae, characterised by regional lymphadenopathy. Rarer presentations, such as osteomyelitis, can occur.We present an adolescent girl with severe right lumbar pain and fever, without animal contacts or recent travels. On examination, pain on flexion of torso, movement limitation and marked lordosis were noted, but there were no inflammatory signs, palpable masses or lymph nodes. Serological investigations revealed elevated inflammatory markers. Imaging revealed a paravertebral abscess with bone erosion. Several microbiological agents were ruled out. After a second CT-guided biopsy, PCR for Bartonella spp was positive. At this point, the family recalled having a young cat some time before. Cat-scratch disease was diagnosed, and complete recovery achieved after treatment with doxycycline and rifampicin.Cat-scratch disease is a challenging diagnosis in the absence of typical features. However, B. henselae must be investigated if common pathogens are ruled out and response to therapy is poor.

Prospects and challenges for the application of tissue engineering technologies in the treatment of bone infections.

Osteomyelitis is a devastating disease caused by microbial infection in deep bone tissue. Its high recurrence rate and impaired restoration of bone deficiencies are major challenges in treatment. Microbes have evolved numerous mechanisms to effectively evade host intrinsic and adaptive immune attacks to persistently localize in the host, such as drug-resistant bacteria, biofilms, persister cells, intracellular bacteria, and small colony variants (SCVs). Moreover, microbial-mediated dysregulation of the bone immune microenvironment impedes the bone regeneration process, leading to impaired bone defect repair. Despite advances in surgical strategies and drug applications for the treatment of bone infections within the last decade, challenges remain in clinical management. The development and application of tissue engineering materials have provided new strategies for the treatment of bone infections, but a comprehensive review of their research progress is lacking. This review discusses the critical pathogenic mechanisms of microbes in the skeletal system and their immunomodulatory effects on bone regeneration, and highlights the prospects and challenges for the application of tissue engineering technologies in the treatment of bone infections. It will inform the development and translation of antimicrobial and bone repair tissue engineering materials for the management of bone infections.

Shotgun metagenomic analysis of saliva microbiome suggests Mogibacterium as a factor associated with chronic bacterial osteomyelitis.

Osteomyelitis of the jaw is a severe inflammatory disorder that affects bones, and it is categorized into two main types: chronic bacterial and nonbacterial osteomyelitis. Although previous studies have investigated the association between these diseases and the oral microbiome, the specific taxa associated with each disease remain unknown. In this study, we conducted shotgun metagenome sequencing (≥10 Gb from ≥66,395,670 reads per sample) of bulk DNA extracted from saliva obtained from patients with chronic bacterial osteomyelitis (N = 5) and chronic nonbacterial osteomyelitis (N = 10). We then compared the taxonomic composition of the metagenome in terms of both taxonomic and sequence abundances with that of healthy controls (N = 5). Taxonomic profiling revealed a statistically significant increase in both the taxonomic and sequence abundance of Mogibacterium in cases of chronic bacterial osteomyelitis; however, such enrichment was not observed in chronic nonbacterial osteomyelitis. We also compared a previously reported core saliva microbiome (59 genera) with our data and found that out of the 74 genera detected in this study, 47 (including Mogibacterium) were not included in the previous meta-analysis. Additionally, we analyzed a core-genome tree of Mogibacterium from chronic bacterial osteomyelitis and healthy control samples along with a reference complete genome and found that Mogibacterium from both groups was indistinguishable at the core-genome and pan-genome levels. Although limited by the small sample size, our study provides novel evidence of a significant increase in Mogibacterium abundance in the chronic bacterial osteomyelitis group. Moreover, our study presents a comparative analysis of the taxonomic and sequence abundances of all genera detected using deep salivary shotgun metagenome data. The distinct enrichment of Mogibacterium suggests its potential as a marker to distinguish between patients with chronic nonbacterial osteomyelitis and chronic bacterial osteomyelitis, particularly at the early stages when differences are unclear.

Osteomyelitis is associated with increased anti-inflammatory response and immune exhaustion.

Introduction: Osteomyelitis (OMS) is a bone infection causing bone pain and severe complications. A balanced immune response is critical to eradicate infection without harming the host, yet pathogens manipulate immunity to establish a chronic infection. Understanding OMS-driven inflammation is essential for disease management, but comprehensive data on immune profiles and immune cell activation during OMS are lacking. Methods: Using high-dimensional flow cytometry, we investigated the detailed innate and adaptive systemic immune cell populations in OMS and age- and sex-matched controls. Results: Our study revealed that OMS is associated with increased levels of immune regulatory cells, namely T regulatory cells, B regulatory cells, and T follicular regulatory cells. In addition, the expression of immune activation markers HLA-DR and CD86 was decreased in OMS, while the expression of immune exhaustion markers TIM-3, PD-1, PD-L1, and VISTA was increased. Members of the T follicular helper (Tfh) cell family as well as classical and typical memory B cells were significantly increased in OMS individuals. We also found a strong correlation between memory B cells and Tfh cells. Discussion: We conclude that OMS skews the host immune system towards the immunomodulatory arm and that the Tfh memory B cell axis is evident in OMS. Therefore, immune-directed therapies may be a promising alternative for eradication and recurrence of infection in OMS, particularly in individuals and areas where antibiotic resistance is a major concern.

Diabetic Foot Infections in the Emergency Department.

Diabetic foot infection (DFI) is among the most common diabetic complications requiring hospitalization. Prompt emergency department diagnosis and evidence-based management can prevent eventual amputation and associated disability and mortality. Underlying neuropathy, arterial occlusion, immune dysfunction, and hyperglycemia-associated dehydration and ketoacidosis can all contribute to severity and conspire to make DFI diagnosis and management difficult. Serious complications include osteomyelitis, necrotizing infection, and sepsis. Practice guidelines are designed to assist frontline providers with correct diagnosis, categorization, and treatment decisions. Management generally includes a careful lower extremity examination and plain x-ray, obtaining appropriate tissue cultures, and evidence-based antibiotic selection tailored to severity.

Osteotomía de descarga ambulatoria mínimamente invasiva en el tratamiento de la úlcera de pie diabético: análisis de 25 pacientes / Minimally invasive offloading osteotomy in the treatment of diabetic foot ulcer: Analysis of 25 patients

Introducción: La diabetes mellitus y sus complicaciones suponen uno de los mayores problemas sanitarios en la actualidad. La úlcera del pie diabético es una de las complicaciones más características. Material, métodos y objetivo: El objetivo es describir los resultados y complicaciones obtenidos en una serie de 25 casos de úlcera neuropática tratada mediante osteotomías de descarga mínimamente invasivas y ambulatorias. Resultados: Del total de intervenciones, 18 fueron sobre úlceras refractarias a un tratamiento conservador previo de una duración media±desviación estándar de 29,28±18,42 meses. El período de seguimiento fue 26,46±4,89 meses. Las tasas agrupadas de respuesta al tratamiento fueron: 100% cicatrización de la úlcera (tiempo medio de cicatrización 22,41±7,01 días), 5,56% recurrencia de la úlcera, 16,67% translocación de la úlcera. En 7 casos se realizó una intervención preventiva sobre áreas con lesiones preulcerosas. Del total, únicamente 3 presentaron infección leve en la zona de la intervención. Conclusiones: La osteotomía de descarga mínimamente invasiva ambulatoria es un procedimiento técnicamente sencillo, que presenta una alta tasa de éxito con mínimas complicaciones en nuestra serie. (AU)

Introduction: Diabetes mellitus and its complications are one of the main burdensome health problems at the present time. The diabetic foot is one of the most characteristic complications. Material, methods and objective: The objective of this work is to describe the results and complications obtained in a series of 25 cases of diabetic foot treated by minimally invasive offloading osteotomies. Results: Of the total number of interventions, 18 were performed on refractory ulcers with prior conservative treatment, for a mean (±SD) duration of 29.28±18.42 months. The mean follow-up period was 26.46±4.89 months. Weighted pooled rates of response to treatment were as follows: 100% for ulcer healing (with a mean healing time of 22.41±7.01 days), 5.56% for ulcer recurrence, and 16.67% for ulcer transfer. In 7cases, a preventive intervention was performed on areas with pre-ulcerative lesions. Of the total number of cases, only 3presented mild infection in the intervention area. Conclusions: Minimally invasive offloading osteotomy is a technically simple intervention, which presents a high success rate with minimal complications in our series. (AU)

Disseminated Cryptococcus neoformans infection involving multiple bones and lung in an immunocompetent patient: a case report.

BACKGROUND: Cryptococcal osteomyelitis is a rare and potentially serious condition, typically encountered in individuals with compromised immune systems. This case underscores the unusual occurrence of disseminated Cryptococcosis in an immunocompetent person, involving multiple bones and lungs, with Cryptococcus neoformans identified as the causative agent. CASE PRESENTATION: An Indonesian man, previously in good health, presented with a chief complaint of successive multiple bone pain lasting for more one month, without any prior history of trauma. Additionally, he reported a recent onset of fever. On physical examination, tenderness was observed in the left lateral chest wall and right iliac crest. Laboratory findings indicated mildly elevated inflammatory markers. A computed tomography (CT) scan of the chest revealed an ovoid solid nodule in the right lower lung and multifocal osteolytic lesions in the sternum, ribs, and humeral head. A magnetic resonance imaging (MRI) study of the sacrum showed multiple lesions in the bilateral iliac bone and the lower L4 vertebral body. Confirmation of Cryptococcal osteomyelitis involved a fine-needle biopsy and culture, identifying Cryptococcus neoformans in the aspirate. The patient responded positively to targeted antifungal treatments, leading to a gradual improvement in his condition. CONCLUSIONS: This case emphasizes the need to consider Cryptococcus neoformans osteomyelitis in immunocompetent patients with bone pain. A definitive diagnosis involves a fine-needle biopsy for pathology and culture, and prompt initiation of appropriate antifungal treatment has proven effective in preventing mortality.

Dilemma with implant placement in patients with florid cemento-osseous dysplasia: A literature review.

METHODOLOGY: An electronic search was done in PUBMED, SCOPUS, and a hand search was done in radiology, periodontology, and oral surgery journals. The search yielded 428 results, from which only 6 articles were selected for this literature review. Both prospective and retrospective studies were included. Clinical studies with information on the pre-implant condition of the site, detailed implant procedure, and follow-up after implant placement of more than 6 months were only considered for this review. RESULTS AND CONCLUSION: Limited clinical studies, shorter follow-up periods were the shortcomings of this review. However, it can be summarized that dental implants should not be placed at the site of FCOD, however can be placed at adjacent sites. Variations in implant type or the implant length had no bearing on the survival of implants at the sites of FCOD.

Causal associations between human gut microbiota and osteomyelitis: a Mendelian randomization study.

Background: Recent studies have emphasized the role of gut microbiota in the onset and progression of osteomyelitis. However, the exact types of gut microbiota and their mechanisms of action remain unclear. Additionally, there is a lack of theoretical support for treatments that improve osteomyelitis by altering the gut microbiota. Methods: In our study, we utilized the largest genome-wide association study (GWAS) meta-analysis to date from the MiBioGen consortium, involving 13,400 participants. The GWAS data for osteomyelitis were sourced from the UK Biobank, which included 4,836 osteomyelitis cases and 486,484 controls. We employed a two-sample Mendelian randomization framework for a detailed investigation into the causal relationship between gut microbiota and osteomyelitis. Our methods included inverse variance weighting, MR-Egger, weighted median, and weighted mode approaches. Additionally, we applied Cochran's Q statistic to assess the heterogeneity of the instrumental variable. Results: At the class level, Bacilli and Bacteroidia were positively correlated with the risk of osteomyelitis. At the order level, only Bacteroidales showed a positive association with osteomyelitis. At the genus level, an increased abundance of Butyricimonas, Coprococcus3, and Tyzzerella3 was positively associated with the risk of osteomyelitis, whereas Lachnospira was negatively associated. Sensitivity analyses showed no evidence of heterogeneity or pleiotropy. Conclusion: This study reveals that classes Bacilli and Bacteroidia, order Bacteroidales, and genera Butyricimonas, Coprococcus3, and Tyzzerella3 are implicated in increasing the risk of osteomyelitis, while the genus Lachnospira is associated with a reduced risk. Future investigations are warranted to elucidate the precise mechanisms through which these specific bacterial groups influence the pathophysiology of osteomyelitis.

Prevalence of multidrug-resistant bacterial infections in diabetic foot ulcers: A meta-analysis.

Multidrug-resistant (MDR) bacterial infections have become increasingly common in recent years due to the increased prevalence of diabetic foot ulcers (DFUs). We carried out a meta-analysis aimed at investigating the prevalence of MDR bacteria isolated from DFUs and analysing the risk factors for MDR bacterial infection in patients with DFUs. The PubMed/Medline, Web of Science, Embase, Cochrane Library, Ovid, Scopus, and ProQuest databases were searched for studies published up to November 2023 on the clinical outcomes of MDR bacteria in DFUs. The main outcome was the prevalence of MDR bacteria in DFUs. A total of 21 studies were included, representing 4885 patients from which 2633 MDR bacterial isolates were obtained. The prevalence of MDR bacteria in DFUs was 50.86% (95% confidence interval (CI): 41.92%-59.78%). The prevalence of MDR gram-positive bacteria (GPB) in DFUs was 19.81% (95% CI: 14.35%-25.91%), and the prevalence of MDR gram-negative bacteria (GNB) in DFUs was 32.84% (95% CI: 26.40%-39.62%). MDR Staphylococcus aureus (12.13% (95% CI: 8.79%-15.91%)) and MDR Enterococcus spp. (3.33% (95% CI: 1.92%-5.07%)) were the main MDR-GPB in DFUs. MDR Escherichia coli, MDR Pseudomonas aeruginosa, MDR Enterobacter spp., MDR Klebsiella pneumoniae, and MDR Proteus mirabilis were the main MDR-GNB in DFUs. The prevalence rates were 6.93% (95% CI: 5.15%-8.95%), 6.01% (95% CI: 4.03%-8.33%), 3.59% (95% CI: 0.42%-9.30%), 3.50% (95% CI: 2.31%-4.91%), and 3.27% (95% CI: 1.74%-5.21%), respectively. The clinical variables of diabetic foot ulcer patients infected with MDR bacteria and non-MDR bacteria in the included studies were analysed. The results showed that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization and previous use of antibacterial drugs were significantly different between the MDR bacterial group and the non-MDR bacterial group. We concluded that there is a high prevalence of MDR bacterial infections in DFUs. The prevalence of MDR-GNB was greater than that of MDR-GPB in DFUs. MDR S. aureus was the main MDR-GPB in DFUs, and MDR E. coli was the main MDR-GNB in DFUs. Our study also indicated that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization, and previous use of antibacterial drugs were associated with MDR bacterial infections in patients with DFUs.

Clinical outcomes of perforator-based propeller flaps versus free flaps in soft tissue reconstruction for lower leg and foot trauma: a retrospective single-centre comparative study.

BACKGROUND: The efficacy and safety of perforator-based propeller flaps (PPF) versus free flaps (FF) in traumatic lower leg and foot reconstructions are debated. PPFs are perceived as simpler due to advantages like avoiding microsurgery, but concerns about complications, such as flap congestion and necrosis, persist. This study aimed to compare outcomes of PPF and FF in trauma-related distal lower extremity soft tissue reconstruction. METHODS: We retrospectively studied 38 flaps in 33 patients who underwent lower leg and foot soft tissue reconstruction due to trauma at our hospital from 2015 until 2022. Flap-related outcomes and complications were compared between the PPF group (18 flaps in 15 patients) and the FF group (20 flaps in 18 patients). These included complete and partial flap necrosis, venous congestion, delayed osteomyelitis, and the coverage failure rate, defined as the need for secondary flaps due to flap necrosis. RESULTS: The coverage failure rate was 22% in the PPF group and 5% in the FF group, with complete necrosis observed in 11% of the PPF group and 5% of the FF group, and partial necrosis in 39% of the PPF group and 10% of the FF group, indicating no significant difference between the two groups. However, venous congestion was significantly higher in 72% of the PPF group compared to 10% of the FF group. Four PPFs and one FF required FF reconstruction due to implant/fracture exposure from necrosis. Additionally, four PPFs developed delayed osteomyelitis post-healing, requiring reconstruction using free vascularized bone graft in three out of four cases. CONCLUSIONS: Flap necrosis in traumatic lower-leg defects can lead to reconstructive failure, exposing implants or fractures and potentially causing catastrophic outcomes like osteomyelitis, jeopardizing limb salvage. Surgeons should be cautious about deeming PPFs as straightforward and microsurgery-free procedures, given the increased complication rates compared to FFs in traumatic reconstruction. DATA ACCESS STATEMENT: The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Identification of pathogen composition in a Chinese population with iatrogenic and native vertebral osteomyelitis by using mNGS.

BACKGROUND: Early antimicrobial therapy is crucial regarding the prognosis of vertebral osteomyelitis, but early pathogen diagnosis remains challenging. OBJECTIVE: In this study, we aimed to differentiate the types of pathogens in iatrogenic vertebral osteomyelitis (IVO) and native vertebral osteomyelitis (NVO) to guide early antibiotic treatment. METHODS: A total of 145 patients, who had confirmed spinal infection and underwent metagenomic next-generation sequencing (mNGS) testing, were included, with 114 in the NVO group and 31 in the IVO group. Using mNGS, we detected and classified 53 pathogens in the 31 patients in the IVO group and 169 pathogens in the 114 patients in the NVO group. To further distinguish IVO from NVO, we employed machine learning algorithms to select serum biomarkers and developed a nomogram model. RESULTS: The results revealed that the proportion of the Actinobacteria phylum in the NVO group was approximately 28.40%, which was significantly higher than the 15.09% in the IVO group. Conversely, the proportion of the Firmicutes phylum (39.62%) in the IVO group was markedly increased compared to the 21.30% in the NVO group. Further genus-level classification demonstrated that Staphylococcus was the most common pathogen in the IVO group, whereas Mycobacterium was predominant in the NVO group. Through LASSO regression and random forest algorithms, we identified 5 serum biomarkers including percentage of basophils (BASO%), percentage of monocytes (Mono%), platelet volume (PCT), globulin (G), activated partial thromboplastin time (APTT) for distinguishing IVO from NVO. Based on these biomarkers, we established a nomogram model capable of accurately discriminating between the two conditions. CONCLUSION: The results of this study hold promise in providing valuable guidance to clinical practitioners for the differential diagnosis and early antimicrobial treatment of vertebral osteomyelitis.

Occurrence and significance of elevated D-dimer levels in different types of osteomyelitis: a clinical study.

OBJECTIVE: Plasma D-dimer levels >0.5 mg/L are encountered in various conditions besides venous thromboembolism (VTE). Recent studies use them as a prognostic indicator for systemic and inflammatory diseases. The clinical significance of abnormal levels is unclear in osteomyelitis patients with baseline elevation. Our study reviews the occurrence and significance of >0.5 mg/L D-dimer levels in different types of osteomyelitis. PATIENTS AND METHODS: This study involved 125 individuals, out of which 94 were male and 31 were female. The patients were divided into two groups based on the results of bacterial culture testing. Group A comprised those who tested positive for bacterial culture, while group B included those who tested negative. Out of 68 samples tested, 56% were found to have Staphylococcus aureus. All 125 patients underwent blood testing, which included measuring the D-dimer levels, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), lymphocyte to monocyte ratio (LMR), and MHR monocyte to high-density lipoprotein cholesterol (HDL-C) ratio in different types of osteomyelitis. The statistical analysis of these tests was carried out. RESULTS: Although there were no significant differences in white blood cell (WBC) count, Neutrophil count, Lymphocyte count, or erythrocyte sedimentation rate (ESR) as well as the NLR, PLR, LMR, MHR, HDL-C ratio. The C-reactive protein (CRP) levels were significantly higher in group A (26.13±50.30) than in group B (10.76±18.70) (p<0.05). D-dimer levels were elevated in 40.8% of patients with bacterial culture-positive osteomyelitis, negative culture osteomyelitis, implants with fractures, and no trauma osteomyelitis. No correlation was found between the increase in D-dimer levels and the presence of bacterial culture or implant-related osteomyelitis in patients. CONCLUSIONS: No significant correlation was found between D-dimers and osteomyelitis, including positive bacterial cultures, implant-related osteomyelitis, or osteomyelitis without trauma. However, 40% of the patients had higher D-dimer levels.

Radiological manifestations and clinical findings of patients with oncologic and osteoporotic medication-related osteonecrosis of the jaw.

Medication-related osteonecrosis of the jaw (MRONJ) poses a challenging form of osteomyelitis in patients undergoing antiresorptive therapies in contrast to conventional osteomyelitis. This study aimed to compare the clinical and radiological features of MRONJ between patients receiving low-dose medications for osteoporosis and those receiving high-dose medications for oncologic purposes. The clinical, panoramic radiographic, and computed tomography data of 159 patients with MRONJ (osteoporotic group, n = 120; oncologic group, n = 39) who developed the condition after using antiresorptive medications for the management of osteoporosis or bone malignancy were analyzed. The osteoporotic group was older (75.8 vs. 60.4 years, p < 0.01) and had a longer duration of medication usage than the oncologic group (58.1 vs. 28.0 months, p < 0.01). Pus discharge and swelling were more common in the osteoporotic group (p < 0.05), whereas bone exposure was more frequent in the oncologic group (p < 0.01). The mandibular cortical index (MCI) in panoramic radiographs was higher in the osteoporotic group (p < 0.01). The mean sequestra size was larger in the oncologic group than in the osteoporotic group (15.3 vs. 10.6 mm, p < 0.05). The cured rate was significantly higher in the osteoporotic group (66.3% vs. 33.3%, p < 0.01). Oncologic MRONJ exhibited distinct clinical findings including rapid disease onset, fewer purulent signs, and lower cure rates than osteoporotic MRONJ. Radiological features such as sequestrum size on CT scan, and MCI values on panoramic radiographs, may aid in differentiating MRONJ in osteoporotic and oncologic patients.

Clinical and ultrasound features of 46 children with suppurative osteoarthritis: experience from two centers.

OBJECTIVE: Diagnosing musculoskeletal infections in children is challenging. In recent years, with the advancement of ultrasound technology, high-resolution ultrasound has unique advantages for musculoskeletal children. The aim of this work is to summarize the ultrasonographic and clinical characteristics of children with pyogenic arthritis and osteomyelitis. This study provides a simpler and more effective diagnostic basis for clinical treatment. METHODS: Fifty children with osteomyelitis or arthritis were diagnosed via ultrasound, and the results of the ultrasound diagnosis were compared with those of magnetic resonance imaging and surgery. Clinical and ultrasound characteristics were also analyzed. RESULTS: Out of 50 patients, 46 were confirmed to have suppurative infection by surgical and microbiological examination. Among these 46 patients, 26 were diagnosed with osteomyelitis and 20 had arthritis. The manifestations of osteomyelitis were subperiosteal abscess (15 patients), bone destruction (17 patients), bone marrow abscess (9 patients), and adjacent joint abscess (13 patients). Osteomyelitis mostly affects the long bones of the limbs, femur and humerus (10 and 9 patients, respectively), followed by the ulna, radius, tibia and fibula (one patient each). The manifestations of arthritis were joint pus (20 patients) and joint capsule thickening (20 patients), and hip dislocation (8 patients). All the patients had arthritis involving the hip joint. CONCLUSION: Subperiosteal abscess, bone destruction, and joint abscess with dislocation are ultrasonographic features of pyogenic osteoarthritis. The findings of this work can improve the early diagnosis and differentiation of pyogenic osteoarthritis and provide a reliable basis for treatment.

Infection After Lower-Limb Osseointegration: A Single-Center Retrospective Evaluation of Pathogens, Management, and Outcomes.

PURPOSE: Osseointegration (OI) is a novel alternative to traditional socket-suspended prostheses for lower-limb amputees, eliminating the socket-skin interface and allowing for weight bearing directly on the skeletal system. However, the stoma through which the implant attaches to the external prosthesis creates an ingress route for bacteria, and infection rates as high as 66% have been reported. The aims of this study are to classify infection management and long-term outcomes in this patient population to maximize implant salvage. METHODS: An institutional review board-approved retrospective analysis was performed on all patients who underwent lower-limb OI at our institution between 2017 and 2022. Demographic, operative, and outcome data were collected for all patients. Patients were stratified by the presence and severity of infection. Chi-square and t tests were performed on categorical and continuous data, respectively, using an alpha of 0.05. RESULTS: One hundred two patients met our study criteria; 62 had transfemoral OI and 40 had transtibial OI. Patients were followed for 23.8 months on average (range, 3.5-63.7). Osteomyelitis was more likely than soft tissue infection to be polymicrobial in nature (71% vs 23%, P < 0.05). Infections at the stoma were mostly (96%) managed with oral antibiotics alone, whereas deeper soft tissue infections also required intravenous antibiotics (75%) or operative washout (19%). Osteomyelitis was managed with intravenous antibiotics and required operative attention; 5 (71%) underwent washout and 2 (29%) underwent explantation. Both implants were replaced an average of 3.5 months after explantation. There was no correlation between history of soft tissue infection and development of osteomyelitis (P > 0.05). The overall implant salvage rate after infection was 96%. CONCLUSIONS: This study describes our institution's experience managing infection after OI and soft tissue reconstruction. Although infections do occur, they are easily treatable and rarely require operative intervention. Explantation due to infection is rare and can be followed up with reimplantation, reaffirming that OI is a safe and effective treatment modality.