BACKGROUND: Managing wounds of the lateral malleolus is challenging owing to limited nearby tissues and possibly injured or inadequate vessels for free flaps, especially in case of underlying infections. Moreover, free flaps require specialized skills and are not suitable for every patient. Therefore, identifying reliable local alternatives is crucial. This retrospective study investigated the efficacy and safety of the distally based peroneus brevis muscle flap in treating complex and infected soft-tissue defects of the lateral malleolus.
METHODS: A retrospective medical chart review of all patients who underwent a distally based peroneus brevis muscle flap reconstruction in the context of an infected lateral malleolus defect at Geneva University Hospitals between October 2020 and January 2024 was performed.
RESULTS: Ten patients underwent lateral malleolus reconstruction using a distally based peroneus brevis muscle flap primarily to address post-traumatic infections. Flap coverage was performed within 4 weeks of infection onset for post-traumatic cases, alongside antibiotic treatment. The defects were moderate in size, with a median width of 2.5 cm and length of 5.5 cm. There were no complete or partial flap failures. All patients regained the ability to walk within 5 days after surgery.
CONCLUSIONS: The distally based peroneus brevis muscle flap was efficient in managing complex and infected soft-tissue defects of the lateral malleolus, with control of infection in all patients and minimal donor-site morbidity.

Osteomyelitis is an invasive bone infection that can lead to severe pain and even disability, posing a challenge for orthopedic surgery. Naringin can reduce bone-related inflammatory conditions. This study aimed to elucidate the function and mechanism of naringin in a Staphylococcus aureus-induced mouse model of osteomyelitis. Femurs of S. aureus-infected mice were collected after naringin administration and subjected to microcomputed tomography to analyze cortical bone destruction and bone loss. Bacterial growth in femurs was also assessed. Proinflammatory cytokine levels in mouse femurs were measured using enzyme-linked immunosorbent assays. Pathological changes and bone resorption were analyzed using hematoxylin and eosin staining and tartrate-resistant acid phosphatase staining, respectively. Quantitative reverse transcription polymerase chain reaction and western blot analysis were used to quantify the messenger RNA and protein expression of osteogenic differentiation-associated genes in the femurs. The viability of human bone marrow-derived stem cells (hBMSCs) was determined using cell counting kit-8. Alizarin Red S staining and alkaline phosphatase staining were performed to assess the formation of mineralization nodules and bone formation in vitro. Notch signaling-related protein levels in femur tissues and hBMSCs were assessed using western blot analysis. Experimental results revealed that naringin alleviated S. aureus-induced cortical bone destruction and bone loss in mice by increasing the bone volume/total volume ratio. Naringin suppressed S. aureus-induced bacterial growth and inflammation in femurs. Moreover, it alleviated histopathological changes, inhibited bone resorption, and increased the expression of osteogenic markers in osteomyelitic mice. It increased the viability of hBMSCs and promoted their differentiation and bone mineralization in vitro. Furthermore, naringin activated Notch signaling by upregulating the protein levels of Notch1, Jagged1, and Hes1 in the femurs of model mice and S. aureus-stimulated hBMSCs. In conclusion, naringin reduces bacterial growth, inflammation, and bone resorption while upregulating the expression of osteogenic markers in S. aureus-infected mice and hBMSCs by activating Notch signaling.

Background: Diabetic foot osteomyelitis (DFO) is a major complication and can lead to significant morbidity and mortality. Systemic antibiotic therapy is often initiated first line to achieve quiescence of infection. To perform a multi-centre case review of systemic antibiotic intervention to treat adults with DFO in England and Wales and compare with national guidelines \'Diabetic foot problems: prevention and management\'. Methods: Eight centres from England and Wales retrospectively collated data from a minimum of five adults (aged ≥ 18 years) from electronic case records. All patients were treated with systemic antibiotics following a new diagnosis of DFO (1 June 2021-31 December 2021). Results: 40 patients (35 males and 5 females) were included; the mean age was 62.3 years (standard deviation (SD) 13.0). Patients commenced systemic oral 14 (35%) or intravenous 26 (65%) antibiotic therapy following a new diagnosis of DFO. Twenty-seven (67.5%) patients were medically or surgically managed in the 12-week period with clinical quiescence of infection. Twenty-one patients (52.5%) had no recurrence of DFO infection within 12 weeks; seventeen (42.5%) of these patients had clinical quiescence of infection with systemic antibiotics alone without surgical intervention and nine (22.5%) of these cases had no recurrence of DFO. There were no cases of major amputation or death. All centres showed significant in-centre variability in systemic antibiotic management; variability was reported in the clinical and quantity indicators specifically to antibiotic selection, single versus dual therapy, mode of delivery and duration of treatment. Conclusions: This case review identifies there is existing variation when treating adults with systemic antibiotics for DFO. Further national guidance is required to standardise service delivery and care to improve patient outcomes.

BACKGROUND: Chronic osteomyelitis is a debilitating bone infection, characterized by a persistent infection over months to years, poses diagnostic and therapeutic challenges due to its insidious nature and potential for severe bone and soft tissue destruction. This systematic review and meta-analysis aims to review the literature on the treatment of chronic osteomyelitis in long bones and assess cure rates in single versus two-stage surgery.
METHODS: Following the PRISMA guidelines and registered with PROSPERO (ID: CRD42021231237), this review included studies that reported on the management of chronic osteomyelitis in long bones using either a planned one-stage or two-stage surgical approach in adult patients. Databases searched included Medline, Embase, Web of Science, CINAHL, HMIC, and AMED, using keywords related to osteomyelitis, long bones, and surgical management. Eligibility criteria focused on adults with chronic osteomyelitis in long bones, with outcomes reported after a minimum follow-up of 12 months. The meta-analysis utilized the random-effects model to pool cure rates.
RESULTS: The analysis included 42 studies with a total of 1605 patients. The overall pooled cure rate was 91% (CI 95%) with no significant difference observed between single-stage and two-stage surgeries (X2 = 0.76, P > 0.05). Complications were reported in 26.6% of cases in single-stage procedures and 27.6% in two-stage procedures, with prolonged wound drainage noted as a common issue. Dead space management techniques varied across studies, with antibiotic-loaded calcium sulphate beads used in 30.4% of cases.
CONCLUSIONS: This meta-analysis reveals no significant difference in cure rates between single and two-stage surgical treatments for chronic osteomyelitis in long bones, supporting the efficacy of both approaches. The current treatment strategy should include a combination of debridement, dead space management using local and systematic antibiotics and soft tissue reconstruction if necessary.

BACKGROUND: Antibiotic-containing carrier systems are one option that offers the advantage of releasing active ingredients over a longer period of time. In vitro sustained drug release from a carrier system consisting of microporous β-TCP ceramic and alginate has been reported in previous works. Alginate dialdehyde (ADA) gelatin gel showed both better mechanical properties when loaded into a β-TCP ceramic and higher biodegradability than pure alginate.
METHODS: Dual release of daptomycin and BMP-2 was measured on days 1, 2, 3, 6, 9, 14, 21, and 28 by HPLC and ELISA. After release, the microbial efficacy of the daptomycin was verified and the biocompatibility of the composite was tested in cell culture.
RESULTS: Daptomycin and the model compound FITC protein A (n = 30) were released from the composite over 28 days. A Daptomycin release above the minimum inhibitory concentration (MIC) by day 9 and a burst release of 71.7 ± 5.9% were observed in the loaded ceramics. Low concentrations of BMP-2 were released from the loaded ceramics over 28 days.

Stress-induced premature senescent (SIPS) cells induced by various stresses deteriorate cell functions. Dasatinib and quercetin senolytics (DQ) can alleviate several diseases by eliminating senescent cells. α-tricalcium phosphate (α-TCP) is a widely used therapeutic approach for bone restoration but induces bone formation for a comparatively long time. Furthermore, bone infection exacerbates the detrimental prognosis of bone formation during material implant surgery due to oral cavity bacteria and unintentional contamination. It is essential to mitigate the inhibitory effects on bone formation during surgical procedures. Little is known that DQ improves bone formation in Lipopolysaccharide (LPS)-contaminated implants and its intrinsic mechanisms in the study of maxillofacial bone defects. This study aims to investigate whether the administration of DQ ameliorates the impairments on bone repair inflammation and contamination by eliminating SIPS cells. α-TCP and LPS-contaminated α-TCP were implanted into Sprague-Dawley rat calvaria bone defects. Simultaneously, bone formation in the bone defects was investigated with or without the oral administration of DQ. Micro-computed tomography and hematoxylin-eosin staining showed that senolytics significantly enhanced bone formation at the defect site. Histology and immunofluorescence staining revealed that the levels of p21- and p16-positive senescent cells, inflammation, macrophages, reactive oxygen species, and tartrate-resistant acid phosphatase-positive cells declined after administering DQ. DQ could partially alleviate the production of senescent markers and senescence-associated secretory phenotypes in vitro. This study indicates that LPS-contaminated α-TCP-based biomaterials can induce cellular senescence and hamper bone regeneration. Senolytics have significant therapeutic potential in reducing the adverse osteogenic effects of biomaterial-related infections and improving bone formation capacity.

BACKGROUND: Heel puncture (HP) in neonates can result in osteomyelitis if done non-aseptically or with incorrect technique. This study summarizes clinical experience with heel puncture-related osteomyelitis of the calcaneus (HP-CO) in newborns.
METHODS: We systematically reviewed studies that examined HP-CO in newborn patients using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Our search included the PubMed, Embase, and Cochrane Library databases until December 31, 2023. We used the National Institutes of Health (NIH) assessment scale to evaluate the quality of our analyzed studies.
RESULTS: This study analyzed 15 neonatal calcaneal osteomyelitis (CO) cases due to HP conducted in six countries from 1976 to 2016. The average age of the cases was 8.87 ± 6.13 days, with an average birth weight of 2367.27 ± 947.59 g. The infants had undergone an average of 9.00 ± 8.90 HP, with 93.33% exhibiting swelling. Staphylococcus aureus was present in 80% of cases. Beta-lactam antibiotics were used, with satisfactory outcomes in 53.33% of cases. However, in seven cases, three patients had flatfoot due to calcaneal deformity, and other complications were observed in some patients after 7-8 years.
CONCLUSIONS: This study offers valuable insights into a rare condition, including its epidemiology, clinical and laboratory characteristics, and treatment options for infants with HP-CO. To prevent the risk of osteomyelitis in this vulnerable group of patients, increasing awareness and maintaining strict aseptic techniques is necessary. We recommend that infants presenting with tenderness, redness, purulent discharge, erythema, or fever and with a history of repeated HP and swollen ankles should be evaluated for suspicion of osteomyelitis. A graphical abstract is avilable for this article.

UNASSIGNED: Reliable animal models are critical for preclinical research and should closely mimic the disease. With respect to route of infection, pathogenic agent, disease progression, clinical signs, and histopathological changes. Sheep have similar bone micro- and macrostructure as well as comparable biomechanical characteristics to humans. Their use in bone research is established, however their use in bone infection research is limited. This systematic review will summarise the key features of the available bone infection models using sheep, providing a reference for further development, validation, and application.
UNASSIGNED: This systematic review was designed according to the PRISMA guidelines and registered with PROSPERO. Quality was assessed using SYRICLE\'s risk of bias tool adapted for animal studies. PubMed, MEDLINE, Web of Science and EMBASE were searched until March 2022.1921 articles were screened by two independent reviewers, and 25 were included for analysis.
UNASSIGNED: Models have been developed in nine different breeds. Staphylococcus aureus was used in the majority of models, typically inoculating 108 colony forming units in tibial or femoral cortical defects. Infection was established with either planktonic or biofilm adherent bacteria, with or without foreign material implanted. Most studies used both radiological and microbiological analyses to confirm osteomyelitis.
UNASSIGNED: There is convincing evidence supporting the use of sheep in bone infection models of clinical disease. The majority of sheep studied demonstrated convincing osteomyelitis and tolerated the infection with minimal complications. Furthermore, the advantages of comparable biology and biomechanics may increase the success for translating in vivo results to successful therapies.
UNASSIGNED: In the realm of preclinical research, the translation to viable clinical therapies is often perilous, and the quest for reliable and representative animal models remains paramount. This systematic review accentuates the largely untapped potential of sheep as large animal models, especially in bone infection research. The anatomical and biomechanical parallels between sheep and human bone structures position sheep as an invaluable asset for studying osteomyelitis and periprosthetic joint infection. This comprehensive exploration of the literature demonstrates the robustness and translational promise of these models. Furthermore, this article underscores the potential applicability for sheep in developing effective therapeutic strategies for human bone infections.

Transarticular external fixation is primarily used for open fractures involving the joint. However, its biggest drawback is the potential forjoint dysfunction. The article reports a successful case with complex open tibial plateau fracture treated using locked plate external fixation technique during bone callus formation stage to replace transarticular external fixation. We present a case of a 55-year-old male who sustained a complex open fracture of the tibial plateau. In addition, he also suffered from multiple rib fractures, a fibula fracture, a clavicle fracture, hemorrhagic shock, and lung contusion. The patient has occurred tibial bone infection after undergoing open reduction and transarticular external fixation for fracture management. Our team skillfully applied locked plate external fixation technique during bone callus formation stage to replace transarticular external fixation. Ultimately, the approach not only successfully controls infection and achieves fracture healing but also preserves knee joint function after five years of follow-up. In conclusion,the application of locked plate external fixation technique during bone callus formation stage to replace transarticular external fixation is a valuable approach that orthopedic clinicians should consider and learn from when managing complex intra-articular fractures.

UNASSIGNED: Distal tibial injuries combining bone loss, articular destruction and infection can be treated through distraction osteogenesis combined with ankle fusion. Bone transport is not without complications. This study investigates our preliminary results using a retrograde prefabricated gentamicin-coated nail (ETN PROtect®) to treat complications after infected bone defects of the distal tibial were managed by ankle arthrodesis and distraction osteogenesis.
UNASSIGNED: This is a retrospective case series study. All consecutive patients with bone transport complications after ankle arthrodesis and distraction osteogenesis who were subsequently operated on using a retrograde ETN PROtect® nail were analysed. The cases occurred between 2017 and 2020. The primary objective was to report on the resolution of the clinical problem and the risk of deep infection after nail implantation.
UNASSIGNED: Five patients have included: two docking site non-unions, two regenerated bone fractures and one hypotrophic regenerated bone. These complications were resolved in all patients (5/5, 100%). A painless, stable and plantigrade ankle arthrodesis was achieved in all cases. No patient developed a local infection or required nail removal (mean follow-up: 35.2 months). The mean LEFS score was 46.8 ± 13.8 and the mean knee ROM was 112 ± 12.7°. All patients tolerated full weight-bearing. All patients were very satisfied with the procedure (mean SAPS score was 93.8 points).
UNASSIGNED: The staged retrograde nailing technique using the ETN PROtect® nail may represent an effective and safe treatment for bone transport complications in high-infection-risk patients. Furthermore, the technique allows simultaneous achievement of ankle arthrodesis. The patients had good functional outcomes and were satisfied with the procedure.
UNASSIGNED: This strategy of using retrograde gentamicin-coated tibial nails offers a solution to resolve bone transport complications while simultaneously achieving functional ankle arthrodesis.
UNASSIGNED: Pujol O, Vicente M, Castellanos S, et al. Preliminary Outcomes of a Staged Percutaneous Retrograde Prefabricated Gentamicin-coated Intramedullary Nail to Manage Complications after Ankle Fusion through Tibial Bone Transport. Strategies Trauma Limb Reconstr 2023;18(3):155-162.