Osteomyelitis-relevant antibiotics at clinical concentrations show limited effectivity against acute and chronic intracellular S. aureus infections in osteocytes.

Osteomyelitis caused by Staphylococcus aureus can involve the persistent infection of osteocytes. We sought to determine if current clinically utilized antibiotics were capable of clearing an intracellular osteocyte S. aureus infection. Rifampicin, vancomycin, levofloxacin, ofloxacin, amoxicillin, oxacillin, doxycycline, linezolid, gentamicin, and tigecycline were assessed for their minimum inhibitory concentration (MIC) and minimum bactericidal concentrations against 12 S. aureus strains, at pH 5.0 and 7.2 to mimic lysosomal and cytoplasmic environments, respectively. Those antibiotics whose bone estimated achievable concentration was commonly above their respective MIC for the strains tested were further assayed in a human osteocyte infection model under acute and chronic conditions. Osteocyte-like cells were treated at 1×, 4×, and 10× the MIC for 1 and 7 days following infection (acute model), or at 15 and 21 days of infection (chronic model). The intracellular effectivity of each antibiotic was measured in terms of CFU reduction, small colony variant formation, and bacterial mRNA expression change. Only rifampicin, levofloxacin, and linezolid reduced intracellular CFU numbers significantly in the acute model. Consistent with the transition to a non-culturable state, few if any CFU could be recovered from the chronic model. However, no treatment in either model reduced the quantity of bacterial mRNA or prevented non-culturable bacteria from returning to a culturable state. These findings indicate that S. aureus adapts phenotypically during intracellular infection of osteocytes, adopting a reversible quiescent state that is protected against antibiotics, even at 10× their MIC. Thus, new therapeutic approaches are necessary to cure S. aureus intracellular infections in osteomyelitis.

Clinical outcomes and complications of S53P4 bioactive glass in chronic osteomyelitis and septic non-unions: a retrospective single-center study.

INTRODUCTION: Dead space management following debridement surgery in chronic osteomyelitis or septic non-unions is one of the most crucial and discussed steps for the success of the surgical treatment of these conditions. In this retrospective clinical study, we described the efficacy and safety profile of surgical debridement and local application of S53P4 bioactive glass (S53P4 BAG) in the treatment of bone infections. METHODS: A consecutive single-center series of 38 patients with chronic osteomyelitis (24) and septic non-unions (14), treated with bioactive glass S53P4 as dead space management following surgical debridement between May 2015 and November 2020, were identified and evaluated retrospectively. RESULTS: Infection eradication was reached in 22 out of 24 patients (91.7%) with chronic osteomyelitis. Eleven out of 14 patients (78.6%) with septic non-union achieved both fracture healing and infection healing in 9.1 ± 4.9 months. Three patients (7.9%) developed prolonged serous discharge with wound dehiscence but healed within 2 months with no further surgical intervention. Average patient follow-up time was 19.8 months ± 7.6 months. CONCLUSION: S53P4 bioactive glass is an effective and safe therapeutic option in the treatment of chronic osteomyelitis and septic non-unions because of its unique antibacterial properties, but also for its ability to generate a growth response in the remaining healthy bone at the bone-glass interface.

Management of infected bone defects of the femoral shaft by Masquelet technique: sequential internal fixation and nail with plate augmentation.

BACKGROUND: To evaluate the effectiveness of a sequential internal fixation strategy and intramedullary nailing with plate augmentation (IMN/PA) for bone reconstruction in the management of infected femoral shaft defects using the Masquelet technique. METHODS: We performed a retrospective descriptive cohort study of 21 patients (mean age, 36.4 years) with infected bone defects of the femoral shaft treated by the Masquelet technique with a minimum follow-up of 18 months after second stage. After aggressive debridement, temporary stabilisation (T1) was achieved by an antibiotic-loaded bone cement spacer and internal fixation with a bone cement-coated locking plate. At second stage (T2), the spacer and the locking plate were removed following re-debridement, and IMN/PA was used as definitive fixation together with bone grafting. We evaluated the following clinical outcomes: infection recurrence, bone union time, complications, and the affected limb's knee joint function. RESULTS: The median and quartiles of bone defect length was 7 (4.75-9.5) cm. Four patients required iterative debridement for infection recurrence after T1. The median of interval between T1 and T2 was 10 (9-19) weeks. At a median follow-up of 22 (20-27.5) months, none of the patients experienced recurrence of infection. Bone union was achieved at 7 (6-8.5) months in all patients, with one patient experiencing delayed union at the distal end of bone defect due to screws loosening. At the last follow-up, the median of flexion ROM of the knee joint was 120 (105-120.0)°. CONCLUSIONS: For infected femoral shaft bone defects treated by the Masquelet technique, sequential internal fixation and IMN/PA for the reconstruction can provide excellent mechanical stability, which is beneficial for early functional exercise and bone union, and does not increase the rate of infection recurrence.

Etiology and antimicrobial resistance patterns in chronic osteomyelitis of the tibia: an 11-year clinical experience.

PURPOSE: To analyze changes in tendency of etiology and of antimicrobial resistance patterns to most common local and systemic antibiotics in chronic osteomyelitis of the tibia (COM-T) in a Level I trauma center over an 11-year period. METHODS: A retrospective review including all patients with COM-T who were surgically treated from January 2009 to December 2019. Patients were divided into two period groups: 2009-2014 and 2015-2019. Microbiologic etiology was analyzed. Bacterial resistance patterns evaluation was based on the Magiorakos et al. classification, including proportions of multidrug-resistant organisms (MDROs, acquired non-susceptibility to at least one agent in three or more antimicrobial categories), extensively drug-resistant (XDR) and pan drug-resistant (PDR) organisms encountered. RESULTS: A total of 173 episodes of COM-T were identified. Monomicrobial infections represented 47.4% of all cases, while 28.3% had polymicrobial infections. Negative deep-bone cultures were identified in 24.3% of the patients. The most commonly isolated microorganisms were coagulase-negative Staphylococci (24.5%) and S. aureus (20.5%). No differences were found when comparing Gram-positive infections between periods (58.3% for 2009-2014 vs. 46.7% for 2015-2019; p = 0.10). Findings were similar for Gram-negative infections (37% vs. 33.7%; p = 0.62), although more polymicrobial infections were detected (24.7% vs. 33.3%, respectively; p = 0.359). MDROs were involved in 15% of the cases, with an upward trend when comparing both periods (12.8% vs. 23.6%; p = 0.07). The most-used combination of local antibiotics-glycopeptide (vancomycin) plus aminoglycoside (gentamicin or tobramycin)-was met with low rates of resistance in the most frequently isolated microorganisms. CONCLUSION: According to the results of the present study, rates of Gram-positive and Gram-negative infections remained consistent during the two study periods, but with an upward trend in MDRO and polymicrobial infections detected. The local combination of a glycopeptide plus an aminoglycoside was effective in treating the most frequently isolated microorganisms.

Composition of pathogenic microorganism in chronic osteomyelitis based on metagenomic sequencing and its application value in etiological diagnosis.

BACKGROUND: Traditionally, conventional microbiological culture methods have been used to detect pathogenic microorganisms in chronic osteomyelitis. However, these methods have been found to have a low detection rate, complicating the precise guidance of infection treatment. This study employed metagenomic next-generation sequencing (mNGS) to detect these microorganisms in chronic osteomyelitis with three main objectives: 1). Gain a deeper understanding of the composition of pathogenic microorganisms in chronic osteomyelitis. 2). Compare the microbial detection rates between mNGS and the standard culture methods used in laboratories to enhance the effectiveness of the traditional culture methods. 3). Explore the potential of mNGS in etiological diagnosis. METHODS: Fifty clinically confirmed intraoperative bone tissue samples of chronic osteomyelitis from January 2021 to December 2021 were collected and subjected to mNGS and microbiological testing, respectively. The orthopaedic surgeon combined clinical manifestations and related examinations to determine the causative pathogens. RESULTS: The culture method obtained 29 aerobic and parthenogenic anaerobic bacteria, 3 specific anaerobic bacteria, and 1 yeast-like fungus. Thirty-six aerobic and parthenogenic anaerobic bacteria, 11 specific anaerobic bacteria, and 1 yeast-like fungus were obtained by mNGS, and 2 Mycobacterium tuberculosis(MTB) strains were detected. However, there was no significant difference in the overall positive detection rate between mNGS and the culture method (P = 0.07), and the two were not statistically significant in detecting aerobic and partly anaerobic bacteria (P = 0.625). But, mNGS was significantly superior to culture in detecting anaerobic bacteria and Mycobacterium tuberculosis (P<0.05). CONCLUSIONS: The mNGS method has enhanced our understanding of the distribution of pathogenic microorganisms in chronic osteomyelitis. Traditional culture methods help isolate and cultivate aerobic and facultative anaerobic bacteria, and fungi, and are also utilized for antibacterial drug sensitivity tests. However, mNGS has shown superior capabilities in detecting anaerobic bacteria, MTB, and mixed infection bacteria. This finding offers invaluable guidance for improving laboratory microbial culture and detection conditions. Hence, mNGS should be judiciously used for chronic osteomyelitis, and PCR can be implemented for certain difficult-to-culture microorganisms, such as MTB.

Negative pressure wound therapy for flap closed-incisions after 3D-printed prosthesis implantation in patients with chronic osteomyelitis with soft tissue defects.

BACKGROUND: The flap closed-incisions healing after 3D-printed prosthesis implantation in Chronic Osteomyelitis with Soft Tissue Defects (COSTD) is critical. This study aimed to explore the safety and effectiveness of Negative Pressure Wound Therapy (NPWT) in promoting flap closed-incisions healing. METHODS: Retrospective analysis of clinical data was performed, including baseline, surgical and hospitalization information. The efficacy of NPWT was assessed by comparing the ASEPSIS scores, Visual Analogue Scale (VAS), Activity of Daily Living Scale (ADLS), and Lower Extremity Functional Scale (LEFS), as well as the major postoperative complications. RESULTS: The study included 20 patients, 13 received conventional dressing (Control group) and 7 received NPWT treatment (NPWT group). These two groups exhibited a notable disparity in the distribution of ASEPSIS scores, and the median scores were 24 in Control group and 9 in NPWT group (p = 0.001). Eight patients in the Control group experienced major incisional complications, including 7 cases of exudation, 3 cases of infection, 2 cases of non-healing, and 1 case of dehiscence, while none were observed in the NPWT group (p = 0.015). The VAS, ADLS, and LEFS scores were significantly improved in the NPWT group compared to the Control group (p = 0.003, 0.017, and 0.043, respectively). CONCLUSIONS: The study findings suggest that NPWT applied to the healing process of flap closed-incisions after 3D prosthesis implantation in patients with COSTD can reduce the occurrence of postoperative major complications and promote the recovery of lower limb function and daily activities, which should be recommended for clinical practice.

Localization of osteomyelitis lesions for operative eradication of chronic osteomyelitis of the lower extremities by bone SPECT/CT: a feasibility study.

PURPOSE: This study was performed to investigate the feasibility of bone single-photon emission tomography/computed tomography (SPECT/CT) for pre-operative planning of chronic osteomyelitis (COM) of the lower extremities by localization of osteomyelitis lesions. METHODS: From January 2016 to January 2020, we surgically treated ten adult patients with Cierny-Mader type III COM in the tibia or femur for a mean duration of 24.4 months (range 7.0-70.0 months). We conducted pre-operative planning by bone SPECT/CT and localization of osteomyelitis lesions. The treatment consisted of intra-operative eradication of the infective focus and antibiotic administration. The clinical and radiological outcomes were retrospectively analyzed after a minimum of one year of follow-up. RESULTS: The patients were surgically treated by thorough debridement, dead space management, and appropriate antibiotics without bone transport or an external fixator. The location of the hot uptake region on bone SPECT/CT coincided with that of the osteomyelitis lesion, which was confirmed intra-operatively in all patients. At an average of 16.5 ± 4.3 months (range, 13.0-25.0 months), clinical eradication of osteomyelitis was achieved in nine of the ten patients. One patient required amputation due to recurrence of osteomyelitis. A successful clinical outcome was achieved in eight patients; one suffered persistent ankle pain due to a destructive change in the ankle joint despite eradication of the infection. CONCLUSION: Bone SPECT/CT is a feasible method for the localization and eradication of osteomyelitis lesions in COM of the lower extremities and has favourable clinical outcomes. It can also be applied in cases of distorted bony structures caused by previous trauma or surgery, or in the presence of implants.

Surgical management of chronic osteomyelitis: Organisms, recurrence and treatment outcome.

PURPOSE: The study aimed to identify the risk factors of recurrence in chronic osteomyelitis (COM) and to document the microbiological patterns pre- and intra-operatively and at recurrence, if any. METHODS: We performed retrospective review on COM patients treated with surgical debridement and a 6-week course of antibiotics. The patients with symptoms of osteomyelitis for at least 6 weeks, present or past episodes of discharging sinus, documentation of bone sequestration in operative notes or preoperative images were included in the study. Patients with symptoms of osteomyelitis < 6 weeks, lack of history of discharging sinus or lack of evidence of sequestration in preoperative images or intraoperative notes were excluded. Logistic regression models were used to assess the impact of risk factors of recurrence. Cohen-Kappa scores were derived to see the concordance between pre-operative and intra-operative isolates and at recurrence. RESULTS: Totally, 147 COM patients (115 males and 32 females, mean age (33 ± 19) years) were included in this study. Recurrence was noted in 28 patients (19.0%). Polymicrobial growth and extended spectrum beta-lactamase producing Enterobacteriaceae increased the chance of recurrence. Cierny-Mader stage-1, hematogenous aetiology and negative intraoperative culture reduced the chance of recurrence. Concordance between pre-operative and intra-operative cultures was 59.85% (Kappa score 0.526, p < 0.001) and between index surgery and at recurrence was 23.81% (Kappa score 0.155, p < 0.001). Lack of knowledge of causative organism preoperatively did not affect outcome. At mean follow-up (42 ± 15) months, all patients were apparently infection free for at least 1 year. CONCLUSION: Polymicrobial growth and multi-drug resistant organisms increase the risk of recurrence in COM. Patients' age, gender, diabetes mellitus, previous failed treatment, duration of symptoms, haemoglobin, white cell count, C-reactive protein and erythrocyte sedimentation rate at presentation did not have any impact on the recurrence of infection. Pre-operative isolation of organism is of questionable value. Recurrences of infections do occur and are more of re-infections than relapses. Diligent isolation of organism must be attempted even in re-debridements. Even patients with recurrences do well with appropriate debridement and antibiotic therapy.

A Combination of Ilizarov Frame, Externalized Locking Plate and Tibia Bridging for an Adult with Large Tibial Defect and Severe Varus Deformity Due to Chronic Osteomyelitis in Childhood: A Case Report.

Background: Various techniques have been reported to treat large, segmental tibial defects, such as autogenous bone graft, vascularized free fibula transfer and bone transport. We present a case of a 24-year-old male with a 17-year history of chronic osteomyelitis with obvious lower limb length discrepancy and severe varus deformity of the tibia secondary to osteomyelitis in childhood. Aim: The aim of this work is to provide an alternative choice for treating patients in developing countries with severe lower limb deformity caused by chronic osteomyelitis. Case Presentations: Without surgical intervention for a prolonged period of time, the patient was admitted in our institute for corrective surgery. Corrective surgery consisted of three stages: lengthening with Ilizarov frame, removal of Ilizarov frame and fixation with externalized locking plate, and removal of externalized locking plate. Tibia bridging was achieved at the distal and proximal junction. The range of motion (ROM) of the knee joint was nearly normal, but the stiffness of the ankle joint was noticeable. The remaining leg discrepancy of 0.1 cm required no application of a shoe lift. Moreover, the patient could engage in daily activities without noted limping. Conclusions: Distraction-compression osteogenesis using the Ilizarov apparatus is a powerful tool to lengthen the shortened long bone and adjust the deformity of the lower limbs. Externalized locking plates provide an alternative to the traditional bulky external fixator, as its low profile makes it more acceptable to patients without compromising axial and torsional stiffness. In all, a combination of Ilizarov frame, externalized locking plate and tibia bridging is an alternative for patients in similar conditions.

Dead space management strategies in the treatment of chronic osteomyelitis: a retrospective review.

PURPOSE: Dead space management is critically important during the treatment of chronic osteomyelitis. Many dead space management strategies are available, each with their respective advantages and shortcomings. This study aims to present the outcomes and complications of dead space management strategies employed in the treatment of chronic osteomyelitis at a single tertiary level musculoskeletal unit. METHODS: A retrospective review of dead space management strategies employed at a tertiary-level musculoskeletal infection unit was conducted. Patients of any age treated for chronic osteomyelitis of the appendicular skeleton with a minimum follow-up of 6 months were included in the study. Data were collected regarding patient demographics, aetiology and site of infection, dead space management strategy employed, follow-up period and outcome in terms of resolution of infection. RESULTS: A final cohort of 132 patients underwent surgical treatment with a dedicated dead space management strategy for chronic osteomyelitis of the appendicular skeleton. Eleven patients (8%) experienced a recurrence of infection. Seven patients (63%) with recurrence were type B hosts, while four patients (37%) were type A hosts. CONCLUSION: Dead space management is an integral part of treating chronic osteomyelitis; however, no guidelines currently exist regarding the most appropriate strategy. Favourable results are achievable in low to middle-income countries, and it is evident that no dead space management strategy is superior to another. The pursuit for the ideal void filler is ongoing. LEVEL OF EVIDENCE: III.

Treatment of chronic osteomyelitis with antibiotic-impregnated polymethyl methacrylate (PMMA) - the Cierny approach: is the second stage necessary?

BACKGROUND: Chronic osteomyelitis is a challenge for orthopedic surgeons. Most patients with osteomyelitis receive two-stage management according to Cierny-Mader. The first stage includes radical debridement and insertion of an antibiotic-impregnated cement spacer (ACS) (beads, rods, nails, or blocks) into the bone defect. The second stage is performed 6-8 weeks later, when the spacer is removed and a cancellous autograft is placed within the bone defect. The possibility of ACS as definitive management for osteomyelitis, avoiding the second stage, is presented. METHODS: Sixteen patients with osteomyelitis received radical debridement and insertion of an ACS in all forms into the bone defect as a definitive management. In 8 patients, the tibia was infected, 4 had femur infection, 2 humerus, 1 fibula, and 1 ankle. The mean age at the time of the first stage of reconstruction was 49 years (range, 13-71 years). According to the Cierny-Mader classification, 1 patient was C-M IA, another was IB, 7 IIIA, 6 IIIB, and 1 was 4A. All B hosts had systemic illnesses. The mean follow-up period was 6 years (1.5-16 years). RESULTS: No patient exhibited radiographic evidence of excessive bone loss. Signs of recurrence of osteomyelitis were not noted in any of the patients, and no fractures had occurred by the last follow-up. CONCLUSION: Our study suggests that a proportion of patients with planned retention of ACS appear to function well without requiring further surgical intervention, especially in elderly or vulnerable patients.

Four cases of abdominal expander implantation in adult chronic osteomyelitis of lower extremity with soft tissue defect and literature review.

In this study, we intend to explore the clinical efficacy of abdominal expander implantation combined with flap technique in adult chronic osteomyelitis of lower limb with soft tissue defects, and to provide the basis for the promotion of the technique in clinical practice. Four patients diagnosed with chronic osteomyelitis of lower extremity with soft tissue defect were enrolled in this prospective study. Evaluation indicators included state of flap survival, state of abdominal incision, surrounding of abdominal wound scar, satisfaction of the patient, state of flap survival half a year after surgery, whether the 3D prosthesis is successfully implanted and limb movement. Four patients had complete flap survival, two of whom had a small amount of skin graft survival disorder in the vascular pedicle area, which improved after 1 month of dressing change. The expander had an average expansion time of 31.5 days, an average water injection of 525 mL, and an average skin volume taken of 159 cm2 . No incision exudation, incision dehiscence, subcutaneous exudate and other complications occurred. The mean Vancouver Scar Scale score at 3 months after surgery was 3.5 (range from 3 to 6) points. Four patients showed good flap survival at six-month follow-up. 3D printed prosthesis were all successfully implanted. The treatment of adult chronic osteomyelitis of lower extremities with lower abdominal implantable expander combined with flap technique can effectively increase the skin harvesting area, reduce the suture tension of abdominal skin harvesting area and the scar hyperplasia of abdominal skin harvesting area.

Influence of ß-lactam antibiotics on the activity of K. pneumoniae bacteria biofilm forms isolated from wounds of patients with chronic osteomyelitis.

One of the reasons for the emergence of highly resistant strains is associated with the ability of bacteria to form biofilms on various surfaces. The formation of a biofilm by pathogens leads to a decrease in the activity of the antibiotic, an increase in the time for the production of stress response genes by bacteria, and, as a result, an increase in antimicrobial tolerance. To investigate the effect of imipenem and cefepime on the activity of biofilm forms of K. pneumoniae bacteria isolated from the wounds of patients with chronic osteomyelitis. The object of the study is clinical strains of K. pneumoniae isolated from the wounds of patients with chronic osteomyelitis. In the control series, the level of biofilm formation of K. pneumoniae strains was assessed after 48 hours of cultivation on coverslips and 96-well polystyrene plates. In the second and third series, the biofilm form of K. pneumoniae bacteria was exposed to imipenem and cefepime, and after 24 hours the activity of biofilm formation was assessed according to previously developed criteria. The structure of the emerging biofilm on the surface of the coverslip in all series of the experiment was represented by single adherent cells and microcolonies of various sizes. Cultivation with antibiotics led to a decrease in the number of microcolonies ranging in size from 10 to 10,000 µm2 in the second and third series, however, significant differences from the control series were found only when exposed to cefepime. The intensity of film formation of K. pneumoniae in the control series by the tablet method was 0.350 (0.334; 0.368) units opt.pl. When cultivating biofilms together with antibacterial drugs, the biofilm-forming activity after 24 hours of the experiment was significantly lower than in the control group in all experimental series. K. pneumoniae bacteria isolated from patients with chronic osteomyelitis, when cultivated on polystyrene plates and on the surface of coverslips, actively form a biofilm, exhibiting highly adhesive properties. The studied antibiotics were shown to have a bacteriostatic effect on biofilm forms of K. pneumoniae bacteria. The bactericidal effect of imipenem and cefepime on biofilm forms was not revealed.

[SAPHO syndrome : An overview and nosological differentiation of 35 disease cases]. / SAPHO-Syndrom : Ein Überblick und nosologische Differenzierung von 35 Krankheitsfällen.

The SAPHO syndrome is not a single entity but an inhomogeneous, nosologically heterogeneous complex of symptoms with unknown etiology and heterogeneous pathogenesis. Clinically subacute, recurrent or chronic disease processes and a common skin-bone association (skibo disease) can be found. Under the acronym SAPHO, chronically recurrent multifocal osteomyelitis (CRMO) is the most common disease that can occur in youth as well as adolescence. Spondylarthritis hyperostotica pustulo-psoriatica with the triad palmoplantar pustulosis, sternoclavicular hyperostosis and ossifying spinal manifestations is the most common SAPHO form found in adults. Abortive disease forms are the inflammatory anterior chest wall syndrome, extended sternoclavicular hyperostosis syndrome of the clavicle bone, acne CRMO and acne spondylarthritis. The SAPHO disease usually heals with a relatively favorable prognosis but there are also unfavorable courses with functional limitations. The diagnosis should be made based on clinical examination, imaging (x-ray, scintigraphy, magnetic resonance imaging) and/or histological bone biopsy analysis. Treatment should be interdisciplinary. Antibiotic treatment is obsolete. This article provides an overview of the SAPHO syndrome and a clinical-rheumatological imaging differentiation as well as classification of 35 cases at first presentation.

Nonunion After an Open Trimalleolar Ankle Fracture: An Extended Clinical Course and a Novel Approach to Tibio-Talo-Calcaneal Arthrodesis.

Nonunion in the setting of chronic osteomyelitis after severe open ankle fractures is a feared outcome with severe loss in patient quality of life. Tibio-talo-calcaneal arthrodesis is a good salvage treatment option in this difficult patient cohort. We report a case of chronic osteomyelitis with severe destruction of the ankle joint after failed fracture fixation of an open trimalleolar ankle fracture. Fusion was ultimately achieved 5 years later using a novel-staged Masquelet technique with external ring fixator stabilization and bone graft reconstruction including femoral harvested autograft using reamer-irrigator-aspirator. This case shows that infection free arthrodesis of the ankle can be achieved even years after failed treatment. This procedure restored significant quality of life through pain relief and much improved mobility and may be a helpful technique in complex tibio-talo-calcaneal arthrodesis in the setting of chronic osteomyelitis and significant joint destruction.

Rare Intercondylar Distal Femoral Brodie's Abscess in a 21-Year-Old Man Who Refused Medical Care for Three Years after Initial Symptoms.

Brodie's abscess is a rare form of sub-acute osteomyelitis that implies the collection of pus inside bone tissue. The present paper presents an extremely rare case of Brodie's abscess located in the distal femur in a young male patient who refused medical care for three years and presented directly with spontaneous fistula and septic complications. Laboratory tests also suggested chronic septic alterations. Complex imaging investigations including X-ray (RX), computer tomography (CT) and Magnetic Resonance imaging (MRI) confirmed the diagnosis with characteristic aspects, such as the penumbra sign on the T1 weighted MRI image. Management included aggressive debridement, defect reconstruction, and long-term specific antibiotics according to culture harvested intra-operatively. Evolution was positive with inflammatory blood tests returning to physiological values within four weeks and patient full recovery within six months, without any physical deficits. The novelty aspect found in this case presentation is represented by the long-term natural evolution of this pathology, and the fact that even in these conditions, the Brodie's abscess did not evolve into a 'malignant' septic condition, but remained rather benign until the spontaneous fistula prompted the patient to seek medical care.

Chronic Recurrent Multifocal Osteomyelitis Involving the Mandible - A Rare Case Report.

Chronic recurrent multifocal osteomyelitis (CRMO) is an uncommon, aseptic, autoinflammatory condition characterized by multifocal bone lesions with pain, swelling, and frequent exacerbations and remissions. It is noteworthy that these lesions occur without any identifiable etiology or microbiologic finding. The clavicle and metaphyses of the long bones are often involved whereas involvement of the mandible is considered rare. It is usually diagnosed by exclusion of other diseases. As it shares most of its features with the more commonly occurring infective osteomyelitis, patients are often unnecessarily subjected to prolonged courses of antibiotics, serial radiation exposures, and repeated bone biopsies. We present a case of CRMO involving the mandible. Our primary objective is to demonstrate the clinical features of this uncommon disorder, highlighting the radiographic appearance. Familiarity with this condition among radiologists greatly increases the likelihood for early diagnosis and formulating an appropriate treatment plan.

Tibia gap nonunion following sequestrectomy treated with a nonvascularized fibula strut graft.

Chronic osteomyelitis of the tibia is a common sequela of acute osteomyelitis which may present with a bone defect following sequestrectomy. Treatment of the gap nonunion can be done with the ipsilateral fibula as a strut graft when harvested subperiosteally and this leads to good outcome. A 7-year-old girl presented to our facility with a 25 cm defect of her right tibia following sequestrectomy for chronic osteomyelitis in another facility. X-rays revealed a healthy tibia superiorly and inferiorly with an intact fibula. She subsequently had an ipsilateral subperiosteal nonvascularized fibula harvest which was used to fill the tibia defect as a strut graft. The synostosis healed perfectly and the fibula reossified, time to union was 17 weeks, and the patient commenced full weight-bearing thereafter. Management of bone gap following sequestrectomy for chronic osteomyelitis remains a challenge to the orthopedic surgeon. The subperiosteal fibular harvest and use as a strut graft is a viable option with good outcomes. Our experience with this case may serve as a way out of this usual challenge.

Long-Term Compassionate Use of Cefiderocol To Treat Chronic Osteomyelitis Caused by Extensively Drug-Resistant Pseudomonas aeruginosa and Extended-Spectrum-ß-Lactamase-Producing Klebsiella pneumoniae in a Pediatric Patient.

We report a 15 year-old Nigerian adolescent male with chronic osteomyelitis caused by an extensively drug-resistant (XDR) Pseudomonas aeruginosa strain of sequence type 773 (ST773) carrying blaNDM-1 and an extended spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae strain. The patient developed neurological side effects in the form of circumoral paresthesia with polymyxin B and asymptomatic elevation of transaminases with aztreonam (used in combination with ceftazidime-avibactam). Cefiderocol treatment for 14 weeks plus bone implantation resulted in apparent cure and avoided amputation.

Burkholderia pseudomallei peri-prosthetic infection following medial malleolar internal fixation: a case report.

BACKGROUND: Melioidosis-associated peri-prosthetic infection is extremely rare. To date, melioidosis associated septic arthritis of the ankle joint following a medial malleolar internal fixation has not been reported. CASE PRESENTATION: We describe a 49-year-old male with a history of long standing diabetes who presented with fever, constitutional symptoms and right ankle pain for 1 week. Ten years ago, he underwent a medial malleolar screw fixation following a traumatic closed fracture. His initial right ankle radiographs showed no evidence of osteomyelitis. He underwent a wound debridement and washout of the right ankle joint. The peripheral blood and pus from the ankle joint was culture positive for Burkholderia pseudomallei with very high antibody titres. His subsequent radiographs showed features of chronic osteomyelitis. He was treated with a prolonged course of antibiotics and repeated wound debridement. At follow up after 6 months, he had no clinical features of recurrent infection. CONCLUSIONS: Melioidosis should be entertained in the differential diagnosis of peri-prosthetic infections in high risk patients.