Intramedullary Research Articles

Treatment of diametaphyseal forearm fractures in children and adolescents : Antegrade intramedullary nail osteosynthesis and its alternatives

Osteosynthesis in dislocated diametaphyseal forearm fractures is intended to restore anatomy and function. Antegrade intramedullary nailing in the radius is used to restore length, rotation, and axis within the age-specific correction limits. Sufficient stability ensures early functional postoperative treatment without load. Dislocated diametaphyseal forearm or radius fractures that cannot be closed, stably reduced, or remain outside the age-specific correction limits. Radius or forearm fractures located distal or proximal to the defined area. Soft tissue defects, contamination or infections located in the access path. In the course of the Thompson approach, the soft spot between the extensor digitorum and extensor carpi radialis brevis muscles is located and an approx. 3-4 cm skin incision is made. Then blunt preparation down to the bone, sparing the profundus and superficial radial nerve. Retraction of the musculature with two Langenbeck hooks. Opening of the cortex with an awl. If necessary, a2.5 mm drill with tissue protection can be used beforehand if the cortex is very hard. Atitanium elastic nail (TEN) diameter is selected so that it fills approximately 2/3 of the medullary canal. It is recommended to flatten the TEN runner with parallel flattening forceps. After closed reduction, the TEN is then brought up in front of the growth plate with slightly rotating movements. The TEN is bent over at the proximal end and pinched off above the muscle bellies. Alternative procedures include Kirschner wire osteosynthesis or retrograde TEN from radial or dorsal, with or without bending. The aim of osteosynthesis is early functional follow-up without load. Sports abstinence is recommended for 8weeks. Metal removal can be performed after consolidation between 3and 6months. Clearly dislocated or outside the correction limits infantile radius and forearm fractures show very good treatment results with alow risk profile after the described osteosynthesis technique. Pseudarthrosis and nerve damage were not observed. Secondary dislocation has not occurred.

Homozygous synonymous FAM111A variant underlies an autosomal recessive form of Kenny-Caffey syndrome.

FAM111A (family with sequence similarity 111 member A) is a serine protease and removes covalent DNA-protein cross-links during DNA replication. Heterozygous gain-of-function variants in FAM111A cause skeletal dysplasias, such as the perinatal lethal osteocraniostenosis and the milder Kenny-Caffey syndrome (KCS). We report two siblings born to consanguineous parents with dysmorphic craniofacial features, postnatal growth retardation, ophthalmologic manifestations, hair and nail anomalies, and skeletal abnormalities such as thickened cortex and stenosis of the medullary cavity of the long bones suggestive of KCS. Using exome sequencing, a homozygous synonymous FAM111A variant, NM_001312909.2:c.81 G > A; p.Pro27=, that affects the last base of the exon and is predicted to alter FAM111A pre-mRNA splicing, was identified in both siblings. We identified aberrantly spliced FAM111A transcripts, reduced FAM111A mRNA levels, and near-complete absence of FAM111A protein in fibroblasts of both patients. After treatment of patient and control fibroblasts with different concentrations of camptothecin that induces covalent DNA-protein cross-links, we observed a tendency towards a reduced proportion of metabolically active cells in patient compared to control fibroblasts. However, under these culture conditions, we did not find consistent and statistically significant differences in cell cycle progression and apoptotic cell death between patient and control cells. Our findings show that FAM111A deficiency underlies an autosomal recessive form of FAM111A-related KCS. Based on our results and published data, we hypothesize that loss of FAM111A and FAM111A protease hyperactivity, as observed for gain-of-function patient-variant proteins, may converge on a similar pathomechanism underlying skeletal dysplasias.

Quantitative ROI differences for assessment of occult intertrochanteric extension of greater trochanteric fractures on pelvis CT.

To determine if difference in Hounsfield Units (HU) of the medullary bone between the injured and non-injured femurs in patients with greater trochanteric fractures is associated with occult intertrochanteric (IT) extension. Retrospective review was performed of 81 patients (age range 54-102, 54 females and 27 males) who underwent CT and subsequent MRI after identification of a greater trochanteric fracture without evidence of IT extension on radiography and/or CT. Hounsfield units of the injured and non-injured femurs on CT were recorded at the level of the base of the greater trochanter centrally (ROI1) and the level of the upper border of the lesser trochanter posteromedially (ROI2). The difference between the injured and non-injured femur for each ROI1 and ROI2 were calculated. Absence or presence, and if present, extent of IT extension was assessed on MRI. Analysis was performed to determine if there is correlation of difference in density with presence, and extent of occult IT fractures. 81 cases met inclusion criteria, 14 (17%) had no IT extension, 11 (14%) had less than 50% IT extension and 56 (69%) had 50% or greater IT extension. There was statistical significance between presence and absence of IT extension between the injured and non-injured femur for ROI1 (HU) no IT extension median (IQR): 18.8(4-40), ROI1 (HU) present IT extension median (IQR): 65.5(46-90) p < .0001, and for ROI2 no IT extension median (IQR): 3(-8-25.5) and ROI2 present IT extension 51(40.5-76), p < .0001. There was statistical significance of the extent of IT extension: ROI1 less than 50% IT extension median (IQR): 37.5(27.5-57), ROI1 50% or greater IT extension median (IQR): 72.3(53.5-91.3), p < .0001, and for ROI2 less than 50% IT extension median (IQR): 17.5(8-49), and ROI2 50% or greater IT extension median (IQR): 55.8(45.3-81.5), p < .0001. A threshold ROI2 difference of 50 HU resulted in specificity of 92% and sensitivity 60.7% of for IT extension 50% or greater. Patients presenting with greater trochanteric fractures, an asymmetric increased density measured by ROI differences within the medullary space of the IT region between the injured and non-injured femur is associated with occult IT extension.

One-Stage Tibiotalocalcaneal Arthrodesis for Severe Septic Destruction of the Ankle Joint Using a Retrograde Intramedullary Nail: A Retrospective Cross-sectional Study.

Severe septic destruction of the ankle joint poses a therapeutic challenge but lacks a consensus optimal treatment. Tibiotalocalcaneal arthrodesis (TTCA) is considered as a valuable salvage procedure, but the literature remains scarce. Conventional treatment approaches, including 2-stage procedures, have been associated with prolonged recovery times and varying success rates. Many authors prefer classical external fixation in these scenarios, citing concerns that internal implants might pose a risk for recurrent infection. To date, no study has investigated the outcomes of 1-stage surgery using a retrograde intramedullary (IM) nail. The main purpose was to assess the rate of recurrent infection at 2 years following 1-stage TTCA using a retrograde IM nail in severe septic destruction of the ankle joint. Fusion rates and functional outcomes were evaluated as secondary purposes. The clinical and radiologic data of patients who underwent 1-stage TTCA with retrograde IM nail following severe septic destruction of the ankle joint with a minimal follow-up of 2 years were retrospectively analyzed. Reinfection rate, fusion rate, functional outcomes, and complications were evaluated. A total of 25 patients were included with a mean follow-up of 42 months (24-92 months). The mean age was 55 ± 18 years old. At the last follow-up, reinfection occurred in 6 patients (24%) and fusion was obtained in 19 patients (83%). Eight patients (32%) required revision surgery. The mean postoperative modified American Orthopaedic Foot & Ankle Society (AOFAS) score, 12-Item Short Form Health Survey physical and mental component summary scores were respectively 53 ± 19.5, 35.5 ± 11.4, and 46.7 ± 13.5 points. One-stage TTCA with retrograde IM nail appears to be an acceptable alternative in severe septic destruction of the ankle joint, with a high eradication rate of infection and ankle fusion.

Anaerostipes caccae CML199 enhances bone development and counteracts aging-induced bone loss through the butyrate-driven gut–bone axis: the chicken model

BackgroundThe gut microbiota is a key regulator of bone metabolism. Investigating the relationship between the gut microbiota and bone remodeling has revealed new avenues for the treatment of bone-related disorders. Despite significant progress in understanding gut microbiota-bone interactions in mammals, research on avian species remains limited. Birds have unique bone anatomy and physiology to support egg-laying. However, whether and how the gut microbiota affects bone physiology in birds is still unknown. In this study, we utilized laying hens as a research model to analyze bone development patterns, elucidate the relationships between bone and the gut microbiota, and mine probiotics with osteomodulatory effects.ResultsAging led to a continuous increase in bone mineral density in the femur of laying hens. The continuous deposition of medullary bone in the bone marrow cavity of aged laying hens led to significant trabecular bone loss and weakened bone metabolism. The cecal microbial composition significantly shifted before and after sexual maturity, with some genera within the class Clostridia potentially linked to postnatal bone development in laying hens. Four bacterial strains associated with bone development, namely Blautia coccoides CML164, Fournierella sp002159185 CML151, Anaerostipes caccae CML199 (ANA), and Romboutsia lituseburensis CML137, were identified and assessed in chicks with low bacterial loads and chicken primary osteoblasts. Among these, ANA demonstrated the most significant promotion of bone formation both in vivo and in vitro, primarily attributed to butyrate in its fermentation products. A long-term feeding experiment of up to 72 weeks confirmed that ANA enhanced bone development during sexual maturity by improving the immune microenvironment of the bone marrow in laying hens. Dietary supplementation of ANA for 50 weeks prevented excessive medullary bone deposition and mitigated aging-induced trabecular bone loss.ConclusionsThese findings highlight the beneficial effects of ANA on bone physiology, offering new perspectives for microbial-based interventions for bone-related disorders in both poultry and possibly extending to human health.3YvVhM8B6L-RxYm8AZskZyVideo Graphical

Risk Factors for Early Implant Failure in Geriatric Intertrochanteric Fractures Treated with Twin Interlocking Derotation and Compression Screw Cephalomedullary Nail (InterTAN).

Intertrochanteric hip fractures in elderly patients are a significant cause of morbidity and mortality, with increasing incidence due to the aging population. Despite advancements in intramedullary nailing (IMN) technology, fixation failure remains a concern. This study aims to evaluate pre-and postoperative radiographic risk factors for varus collapse in geriatric intertrochanteric fractures treated with twin interlocking derotation and compression screw cephalomedullary nail (InterTAN, Smith & Nephew). This retrospective study included patients over 60 years with AO 31A1 and 31A2 intertrochanteric femur fractures treated with InterTAN at a tertiary referral center from August 2012 to August 2017. Patients with high-energy fractures, AO 31A3 fractures, or those requiring open reduction were excluded. Data on demographics, fracture classification, implant sizes, imaging studies, and follow-up were collected. Radiographic assessments included Chang's medial cortical support concept, tip-apex distance (TAD), calcar-referenced TAD (CalTAD), neck-shaft angles (NSA), and screw placement according to Cleveland zones. Varus collapse was defined as a >5° change in NSA within three months postoperatively. Multivariate logistic regression analysis was used to identify risk factors for varus collapse. The study included 136 patients with a mean age of 79.8 years, of whom 38.2% were male. The early postoperative tipapex distance (TAD) averaged 21.9mm, with 30.1% of patients experiencing varus collapse greater than 5°. Positive medial cortical support (PMCS) or neutral position (NP) type reduction was highly protective against varus collapse (p < 0.001), as well as TAD less than 25mm (p < 0.001). Additionally, the placement of screws in the central-central or central-inferior zones provided a protective effect against varus collapse (p = 0.031). Conversely, having an OTA/AO type A2.2 or A2.3 fracture significantly increased the risk of varus collapse (p = 0.030). Other factors, such as CalTAD and the nail width to medullary canal ratio, did not significantly predict varus collapse (p = 0.831 and p = 0.952, respectively). Our findings align with previous studies highlighting TAD and screw placement as critical factors in preventing fixation failure. The protective effect of PMCS or NP reduction and the increased risk associated with OTA/AO type A2.2 and A2.3 fractures are noteworthy. Unlike previous studies, CalTAD was not significantly associated with varus collapse in our cohort. The study underscores the importance of surgical technique and radiographic parameters in optimizing outcomes for elderly patients with intertrochanteric fractures. In elderly patients treated with InterTAN nails, varus collapse is influenced by fracture type, TAD, reduction quality, and screw placement. Ensuring a TAD <25mm, achieving PMCS or NP reduction, and placing screws in central-central or central-inferior zones are crucial for minimizing varus collapse. These findings highlight the importance of meticulous surgical technique and radiographic assessment in managing intertrochanteric fractures in the elderly. hip fractures, intertrochanteric fractures, internal Fixation, geriatrics, cephalomedullary nail.

How compactness affects long bone resistance to compression-An investigation into the rhinoceros humerus.

The functional signal of bone internal structure has been widely studied. Isolated form-function relationships have often been assumed from the observation of presumed morphofunctional relationships, but have never been truly tested. Indeed, distinct bone microanatomical feature co-evolve in response to various constraints that are difficult to detangle. This study tested for the first time the impact of various microanatomical parameters taken one by one, plus some in pairs, on bone strength under compression using biomechanical modelling. We carried out finite element analyses on humerus models, obtained from a white rhinoceros, with different heterogeneous internal structures, and analysed the magnitude and distribution of von Mises stresses. These tests validated earlier hypotheses of form-function relationships about the greater resistance to compression provided by the thickening of the cortex and the filling of the medullary area by trabecular bone and highlighted the stronger impact of increasing trabecular bone compactness than of avoiding an open medullary cavity. By making it possible to estimate the relative impact of each parameter and ofcombinations of microanatomical features, they also showed the more limited impact of the trabecular bone compactness in the epiphyses to resist compression, and the fact that microanatomical changes of opposite but of similar amplitude impact can compensate each other, but that the impact of the sum of two negative microanatomical changes far exceeds the sum of the impacts of each of the two changes taken separately. These results contribute to a better understanding of bone adaptation and form-function relationships so that they later can be used with confidence for palaeobiological inferences on fossil specimens, contributing to a better understanding of skeletal evolution during the evolutionary history of vertebrates. They also highlight the potential of taking internal structure into account in the bone biomechanical analyses. In addition, they can be used in bioinspiration to design resistant structures subjected to compression.

Differences in Femoral Medullary Canal Dimensions in the USA and East Asian Populations

With emerging technologies and improved operative techniques, cementless total hip arthroplasty is becoming more popular and showing better results. The femoral prosthesis and intramedullary nail should precisely fit in the medullary canal to prevent micromotion and loosening. Most of the femoral prosthesis and nail designs are made from the data obtained from Caucasian femur and may not press fit if used in Asian populations. This study compares the femoral medullary canal diameter in American and Oriental populations at different bony levels. A total of 245 dry femora were collected which included 47 from United States, 77 from China, 44 from Japan, 50 from Korea and 27 from Taiwan, and plan radiographs were taken. Radiographs were digitized to measure the medullary canal width at 20% (lesser trochanter; LT), 35% (supra-isthmus; SI), 50% (mid-isthmus; MI), 65% and 80% of the total femur length. The results revealed significant differences in the medullary canal width between the US and East Asian Oriental populations. The medullary canal in the US population was significantly larger at the LT, SI, MI, and 65% but significantly smaller at 80% of the femoral shaft length compared to the East Asian populations. Among the East Asian populations, significant differences were obse4rved between the Chinese and Taiwanese populations as well as the Japanese and Taiwanese populations. The Taiwanese population had the smallest femoral medullary canal size among the east Asian populations. We conclude that there are significant differences in the femoral medullary width between the American and East Asian populations. These results will be useful for surgeons operating on the proximal or distal femur.

Dynamics of perifocal reactions to the application of antimicrobial gel in one-stage hip replacement under conditions of staphylococcal infection in the experiment

Background. Local antibacterial therapy in the treatment of osteomyelitis significantly increases the effectiveness of surgical debridement.The aim of the work. To assess in an in vivo experiment the dynamics of perifocal tissue reactions to the application of an original polyvinylpyrrolidone-based antimicrobial gel in a one-stage treatment of implant-associated infection in the hip joint in rabbits.Methods. Implant-associated infection was modeled by inserting Staphylococcus aureus-infected wires into the medullary canal of the femur of rabbits (n = 12). On the day 14, we removed the wire and performed radical surgical treatment of the suppurative focus and hip replacement. The animals were divided into two groups: experimental group – with application of the original antimicrobial gel at the stage of hip replacement (n = 6); comparison group – without gel application (n = 6). For morphological studies, animals were sacrificed on the days 10, 45 and 90 after hip replacement, changes in soft tissues and the bone marrow canal were assessed, and cell populations were counted with statistical data processing.Results. The application of the original antimicrobial gel causes statistically significant decrease in the number of neutrophils in the soft tissues surrounding the implant in the comparison group at all stages. Moreover, in the experimental group, at early stages the number of lymphocytes, plasmacytes and macrophages was statistically significantly higher; on the day 45, a statistically significantly larger number of lymphocytes was registered, and on the day 90 – a statistically significantly larger number of multinucleated and epithelioid cells.Conclusion. The experiment histologically confirmed the effectiveness of application of the original antimicrobial gel to stop infectious inflammation in soft tissues and the bone marrow canal during surgical debridement of an osteomyelitic lesion followed by hip replacement. A pronounced giant cell reaction aimed at removing the polyvinylpyrrolidone-based gel requires further research in terms of its outcomes.

Physiological changes in the regulation of calcium and phosphorus utilization that occur after the onset of egg production in commercial laying hens.

At the onset of egg production, physiological changes governing calcium and phosphorus utilization must occur to meet demands for medullary bone formation and eggshell mineralization. The objective of this study was to identify these changes and determine if they are influenced by dietary supplementation with 1α-hydroxycholecalciferol (AlphaD3™, Iluma Alliance). Commercial laying hens fed either a control or AlphaD3-supplemented diet beginning at 18 weeks of age were sampled at 18 (n = 8) and 31 weeks (n = 8/diet) to evaluate mRNA expression associated with calcium and phosphorus utilization in kidney, shell gland, ileum, and liver, circulating vitamin D3 metabolites, and bone quality parameters in humerus, tibia, and keel bone. Though diet did not heavily influence gene expression at 31 weeks, several significant differences were observed between 18- and 31-week-old hens. Heightened sensitivity to hormones regulating calcium and phosphorus homeostasis was observed at 31 weeks, indicated by increased parathyroid hormone receptor 1, calcium-sensing receptor, calcitonin receptor, and fibroblast growth factor 23 receptors in several tissues. Increased renal expression of 25-hydroxylase and vitamin D binding protein ( DBP ) at 31 weeks suggests kidney participates in local vitamin D3 25-hydroxylation and DBP synthesis after egg production begins. Biologically active 1,25(OH)2D3 was higher at 31 weeks, with correspondingly lower inactive 24,25(OH)2D3. Increased expression of plasma membrane calcium ATPase 1 and calbindin in kidney, shell gland, and ileum suggests these are key facilitators of calcium uptake. Elevated renal inorganic phosphorus transporter 1 and 2 and sodium-dependent phosphate transporter IIa at 31 weeks suggests increased phosphorus excretion following hyperphosphatemia due to bone breakdown for eggshell formation. Diet did influence bone quality parameters. Bone mineral density in both humerus and tibia was higher in AlphaD3-supplemented hens at 31 weeks. Tibial bone mineral content increased between 18 and 31 weeks, with AlphaD3-supplemented hens increasing more than control hens. Moreover, control hens exhibited diminished tibial breaking strength at 31 weeks compared to hens at 18 weeks, while AlphaD3-supplemented hens did not. Together, these results indicate supplementation with AlphaD3 enhanced bone mineralization during the medullary bone formation period and elucidate the adaptive pathways regulating calcium and phosphorus utilization after the onset of lay.

Osteomielitis en Brasil: Un análisis epidemiológico de 2019-2023

Introduction Osteomyelitis is a bone infection characterized by the progressive destruction of cortical bone and medullary cavity, and is a relevant disease due to its probable deleterious consequences for patients. Objective: The study aims to investigate the epidemiology of osteomyelitis in Brazil, focusing on hospitalizations by the SUS (Unified Health System) and deaths between 2019 and 2023, to understand regional disparities. Methodology: A cross-sectional descriptive study, with a quantitative approach to the data, through secondary data collected in the Department of Computer Science of the SUS (DATASUS). The data refer to hospital morbidity due to osteomyelitis during the years from 2019 to 2023, with the period evaluated being from January 2019 to December 2023. Results: There were 71,817 hospitalizations for osteomyelitis in Brazil. The Southeast region had the highest prevalence of cases (40.59%) and reached a higher mortality rate than the other regions. It was noted that the ages most affected by the disease are between 40 and 49 years old. Finally, it was verified that in all regions the male sex is more affected than the female sex. Conclusion: Some risk groups were identified in the study; among them, the male sex, age between 40-49 years and the Southeast region due to the high mortality rate from the disease. The high prevalence of the disease and its high morbidity and mortality reinforce the need for early diagnosis and appropriate treatment.

A sauropod tibia with initial fracture from the Middle Jurassic in Yunyang, Chongqing, southwest China

ABSTRACT Among the available palaeopathological results on non-avian dinosaurs, the fracture is the most documented category. Therein, only two sauropod fractured cases have been reported, and no sauropod tibial fracture has been mentioned. In this study, we report a special sauropod tibial fracture from the Middle Jurassic of Yunyang County, Chongqing, southwest China. The morphological observation shows a planar-shaped sauropod tibial fracture, with a rough surface without fracture callus, and does not exhibit other healing manifestations such as swelling. The CT images and energy spectrum data clearly demonstrate the injured cortical bone invaginated into the medullary cavity. Moreover, these data indicate that the tibia fracture is initial, the first valid record of initial fracture in non-avian dinosaurs. This study enhances our knowledge of sauropod limb bone fractures and enriches the pathological information about dinosaur fractures.

Magnetic resonance imaging characteristics of musculoskeletal hydatid disease

Background Hydatid disease is a parasitic infection seen in endemic areas. Musculoskeletal hydatid disease is rarely reported. Purpose To describe the magnetic resonance imaging (MRI) features of musculoskeletal hydatid disease and to highlight the specific findings in the diagnosis of hydatid cysts. Material and Methods The MRI scans of 29 cases diagnosed as musculoskeletal hydatid disease between 2000 and 2022 were retrospectively analyzed. The localization, size, appearance (unilocular or multilocular), signal characteristics, rim sign, presence of internal septa and membrane, and gadolinium enhancement pattern of hydatid cysts were evaluated. Results A total of 29 patients diagnosed with hydatid cyst were included in the study. Of the lesions, 18 were localized in bone and 11 were in soft tissue. The bone hydatid cysts on MRI showed heterogeneous low to intermediate signal intensity on T1-weighted images and high signal intensity on T2-weighted images in the medullary bone. In 15/18 patients, there was also cortical destruction and extension into the adjacent soft tissue planes. In 8/11 cases where the cyst was located in muscle tissue, the “cyst or cysts within a cyst” appearance was observed on MRI. The rim sign was observed in 7/11 cases and the “water lily” sign was noted in 2/11 cases. Conclusion MRI provides valuable information for the diagnosis of hydatid disease with its distinctive imaging features. Knowledge of the different patterns of hydatid cysts on MRI may be helpful in the diagnosis of this disease.

Intramedullary Cylindrical Grafting for Nonunions of the Proximal Fifth Metatarsal

Fractures affecting the proximal fifth metatarsal constitute 25% of all metatarsal fractures, being particularly prevalent in sports due to stress-related incidents. Recognizing fracture patterns and implementing precise management are pivotal to mitigate potential complications, given the proclivity for suboptimal bone healing, and high incidence of nonunions (up to 4% in zone 2/3 fractures). Various methods for graft collection and application have been outlined, ranging from inlay grafts to the straightforward application of bone grafts at the nonunion site. However, the use of inlay grafts may pose challenges in size accuracy and donor site morbidity. We present and describe a novel grafting technique, which we describe as intramedullary bone grafting, exposing its capacity to promote bone healing by filling the medullary canal with cancellous bone. Developed for the treatment of delayed unions or nonunions in zone 2 and 3 fractures of the proximal fifth metatarsal, this innovative technique amalgamates the advantages of both inlay grafting and cancellous grafting. Employing a compacted cylindrical graft, tailored to match the reamed canal’s dimensions, replaces the entire medulla, facilitating the bone healing process. The technique establishes an intramedullary bone bridge across the nonunion site without compromising cortical bone integrity, extending significantly above and below the site. This presents a possible alternative to conventional methods. Furthermore, we illustrate a case involving a professional athlete with a Torg-3 fracture nonunion in zone 3, who underwent this grafting technique alongside anatomic plate fixation. Following a 4-month follow-up, a CT scan revealed complete bone healing, yielding a painless and functionally restored foot. This success enabled the athlete to resume regular practice. Level of Evidence: Level IV.

3D-printed porous titanium rods equipped with vancomycin-loaded hydrogels and polycaprolactone membranes for intelligent antibacterial drug release

Implant-related infections pose significant challenges to orthopedic surgeries due to the high risk of severe complications. The widespread use of bioactive prostheses in joint replacements, featuring roughened surfaces and tight integration with the bone marrow cavity, has facilitated bacterial proliferation and complicated treatment. Developing antibacterial coatings for orthopedic implants has been a key research focus in recent years to address this critical issue. Researchers have designed coatings using various materials and antibacterial strategies. In this study, we fabricated 3D-printed porous titanium rods, incorporated vancomycin-loaded mPEG750-b-PCL2500 gel, and coated them with a PCL layer. We then evaluated the antibacterial efficacy through both in vitro and in vivo experiments. Our coating passively inhibits bacterial biofilm formation and actively controls antibiotic release in response to bacterial growth, providing a practical solution for proactive and sustained infection control. This study utilized 3D printing technology to produce porous titanium rod implants simulating bioactive joint prostheses. The porous structure of the titanium rods was used to load a thermoresponsive gel, mPEG750-b-PCL2500 (PEG: polyethylene glycol; PCL: polycaprolactone), serving as a novel drug delivery system carrying vancomycin for controlled antibiotic release. The assembly was then covered with a PCL membrane that inhibits bacterial biofilm formation early in infection and degrades when exposed to lipase solutions, mimicking enzymatic activity during bacterial infections. This setup provides infection-responsive protection and promotes drug release. We investigated the coating’s controlled release, antibacterial capability, and biocompatibility through in vitro experiments. We established a Staphylococcus aureus infection model in rabbits, implanting titanium rods in the femoral medullary cavity. We evaluated the efficacy and safety of the composite coating in preventing implant-related infections using imaging, hematology, and pathology. In vitro experiments demonstrated that the PCL membrane stably protects encapsulated vancomycin during PBS immersion. The PCL membrane rapidly degraded at a lipase concentration of 0.2 mg/mL. The mPEG750-b-PCL2500 gel ensured stable and sustained vancomycin release, inhibiting bacterial growth. We investigated the antibacterial effect of the 3D-printed titanium material, coated with PCL and loaded with mPEG750-b-PCL2500 hydrogel, using a rabbit Staphylococcus aureus infection model. Imaging, hematology, and histopathology confirmed that our composite antibacterial coating exhibited excellent antibacterial effects and infection prevention, with good safety in trials. Our results indicate that the composite antibacterial coating effectively protects vancomycin in the hydrogel from premature release in the absence of bacterial infection. The outer PCL membrane inhibits bacterial growth and prevents biofilm formation. Upon contact with bacterial lipase, the PCL membrane rapidly degrades, releasing vancomycin for antibacterial action. The mPEG750-b-PCL2500 gel provides stable and sustained vancomycin release, prolonging its antibacterial effects. Our composite antibacterial coating demonstrates promising potential for clinical application.

Silver-quercetin-loaded honeycomb-like Ti-based interface combats infection-triggered excessive inflammation via specific bactericidal and macrophage reprogramming

Excessive inflammation caused by bacterial infection is the primary cause of implant failure. Antibiotic treatment often fails to prevent peri-implant infection and may induce unexpected drug resistance. Herein, a non-antibiotic strategy based on the synergy of silver ion release and macrophage reprogramming is proposed for preventing infection and bacteria-induced inflammation suppression by the organic-inorganic hybridization of silver nanoparticle (AgNP) and quercetin (Que) into a polydopamine (PDA)-based coating on the 3D framework of porous titanium (SQPdFT). Once the planktonic bacteria (e.g., Escherichia coli, Staphylococcus aureus) reach the surface of SQPdFT, released Que disrupts the bacterial membrane. Then, AgNP can penetrate the invading bacterium and kill them, which further inhibits the biofilm formation. Simultaneously, released Que can regulate macrophage polarization homeostasis via the peroxisome proliferators-activated receptors gamma (PPARγ)-mediated nuclear factor kappa-B (NF-κB) pathway, thereby terminating excessive inflammatory responses. These advantages facilitate the adhesion and osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs), concomitantly suppressing osteoclast maturation, and eventually conferring superior mechanical stability to SQPdFT within the medullary cavity. In summary, owing to its excellent antibacterial effect, immune remodeling function, and pro-osteointegration ability, SQPdFT is a promising protective coating for titanium-based implants used in orthopedic replacement surgery.

Solitary medial proximal tibial osteochondromas cause pes anserinus syndrome in adolescents.

Osteochondromas are common bone tumors with hyaline cartilage-covered heads, arising from cortical and medullary bone. Solitary medial proximal tibial osteochondromas (MPTOs) can cause pes anserinus syndrome via compression. However, the literature lacks comprehensive studies on MPTO-related pes anserinus syndrome and its surgical outcomes. The study reviewed 227 patients diagnosed with osteochondroma between January 2018 and January 2022, with 21 patients meeting inclusion criteria: under 19 years, MPTO, surgical excision, histological diagnosis, ≥1-year follow-up. Cases with irregular follow-ups and multiple hereditary exostoses were excluded. Different surgical techniques were employed based on lesion characteristics. Postoperative weight bearing was allowed, and follow-ups involved postoperative complications assessment, clinical data collection, imaging, and functional evaluations using the International Knee Documentation Committee (IKDC) and Hospital for Special Surgery Pediatric Functional Activity Brief Scale scoring systems. The study involved 21 adolescents (15 ± 2 years). Lesion types were predominantly pedunculated (86%) and surgical interventions involved pes anserinus split (76%) or tenoplasty (24%). No significant correlations were observed between lesion dimensions and IKDC scores. Split intervention led to a significant improvement in IKDC scores (p < 0.01), while tenoplasty showed similar results (p < 0.05). Athlete status did not affect IKDC scores significantly, but both athletes and non-athletes demonstrated improvements (p < 0.05). The negative impact of MPTOs causing pes anserinus tendinitis on the patient's quality of life and activity can be completely corrected with surgical treatment. Complete pes anserinus tendon cutting and subsequent repair are recommended if they facilitate surgery. The study underscores the importance of surgical management for MPTO-related pes anserinus syndrome and provides insights into the effectiveness of different surgical techniques.

Ankle Fractures Treated with Locked Fibular Intramedullary Nailing: Description and Outcomes of a Minimally Invasive Open Technique

OBJECTIVES: To describe and report outcomes of a minimally invasive open intramedullary (IM) fibular nailing technique for fixation of ankle fractures. METHODS: Design: Case Series Setting: Urban Level 1 trauma center Patient Selection Criteria: Adult patients with ankle fractures (OTA 44A-C) treated with locked fibular IM nailing via a minimally invasive open technique for fracture and syndesmotic reduction between 2021 and 2024. Outcome Measures and Comparisons: Quality of reduction, complications, and patient-reported outcomes (PRO). RESULTS: A total of 150 consecutive patients operated by a single surgeon were included. Mean age was 53.3 (17-97) years, and mean BMI was 30.6 ± 7.4 kg/m2. 93(62%) patients were female, and 78 (52%) patients were Caucasian. 72 (48%) patients were obese, 40 (27.7%) patients were current/former smokers, 39 (26%) patients were diabetic, and 23 (15.3%) patients had open fractures. 37 (24.7%) patients had isolated lateral malleolus fractures, 48 (32%) had bimalleolar fractures, and 65(43.3%) had trimalleolar fractures. 123 (82%) patients had 2 syndesmotic screws placed, 26 (17.3%) had 1 screw, and 1 (0.7%) had none. Quality of reduction was good for 98%, fair for 2%, and poor for none per McLennan’s criteria. 113 patients (75.3%) were followed until clinical and radiographic union for a mean of 7.6 months (range 3-22) months). 110 patients (97.3%) went on to successful clinical and radiographic union following the index procedure. No patient had a superficial surgical-site infection, and 3 (2.6%) had deep surgical-site infections. 3 patients had a loss of reduction, and 6 patients had implant failure (5 broken syndesmotic screws, and 1 medial malleolus screw). 9 (8%) patients had unplanned reoperations (3 for debridement, 2 for loss of reduction, and 4 for removal of symptomatic implants). Mean ankle range of motion at final follow-up visit was 12.9° (0-40) of dorsiflexion, 39.6° (10-70) of plantarflexion, 23.5° (5-40) of inversion, and 18.2° (5-50) of eversion. Mean PROs at final follow-up visit were: Global Physical Health: 42.4 (23.5-67.6), Global Mental Health: 47.5 (21-67.6), Physical Function: 37.5 (14.7-57.8), Pain: 54.9 (22-72) and Mobility: 36.9 (16-65.3). CONCLUSIONS: Minimally invasive open fibular IM nailing allowed for excellent reduction and results in union with low rates of complications and good patient reported outcomes. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Three-dimensional printed calcium phosphate scaffolds emulate bone microstructure to promote bone regrowth and repair

The interconnected structures in a 3D scaffold allows the movement of cells and nutrients. Therefore, this study aimed to investigate the in-vivo bioactivity of 3D-printed β-tricalcium phosphate (β-TCP) and hydroxyapatite (HAP) scaffolds that replicate biological bone. This study included 24-week-old male New Zealand white rabbits. A cylindrical bone defect with a diameter of 4.5 mm and a depth of 8 mm was created in the lateral aspect of the distal femur. A 3D-printed scaffold was implanted in the right femur (experimental side), whereas the left femur was kept free of implantation (control side). Micro-CT analysis and histological observations of the bone defect site were conducted at 4, 8, and 12 weeks postoperatively to track the bone repair progress. No evidence of new bone tissue formation was found in the medullary cavity of the bone defect on the control side. In contrast, on the experimental side, the 3D scaffold demonstrated sufficient bioactivity, leading to the growth of new bone tissue. Over time, new bone tissue gradually extended from the periphery toward the center, a phenomenon evident in both micro-CT images and biopsy staining. In the current study, we observed that the cells involved in bone metabolism adhered, spread, and proliferated on our newly designed 3D-printed scaffold with a bone microstructure. Therefore, it is suggested that this scaffold has sufficient bioactivity to induce new bone formation and could be expected to be a more useful artificial bone than the existing version.Graphical

Distal blocking screw augmentation in ulnar intramedullary nail fixation of adult forearm diaphyseal fractures.

This study aimed to evaluate the effect of distal blocking screws on the stability and healing of ulnar diaphyseal fractures treated with intramedullary (IM) nails. The primary research question was whether the addition of distal blocking screws enhanced fracture stabilization and promoted faster healing than the standard IM nailing techniques. This retrospective study reviewed medical records of 30 patients with ulnar diaphyseal fractures treated from February 2018 to September 2023. The patients were divided into two groups: those treated using IM nails alone (n = 17) and those treated with using IM nails with distal blocking screws (n = 13). The surgical time, medullary canal space, fracture healing time, and complications were assessed. Functional outcomes were evaluated using the Grace and Eversmann rating system, the DASH scores, and the VAS scores. The addition of distal blocking screws resulted in a slightly longer surgical time (56min vs 47min). However, the group with distal blocking screws had smaller medullary canal space and showed significantly faster fracture healing times (2.3 months vs 3.9 months; p = .036). There were no reported complications of nonunion, nerve injury, or infection in the distal blocking screw group, whereas the IM nail-only group had one case of nonunion (5.7%). The use of distal blocking screws in conjunction with IM nails for ulnar diaphyseal fractures improves fracture stability and promotes faster healing.