A novel primary antibiotic cement-coated locking plate as a temporary fixation for the treatment of open tibial fracture.

Complex lower extremity trauma reconstruction remains a challenge. This study used an internal fixation composite structure of antibiotic cement plates as a temporary fixation to treat lower extremity Grade III open fractures; thus, reducing the treatment period and complications of external fixation. We aimed to assess the safety and efficacy of this technique in the initial surgery stage. Between January 2018 and March 2021, 20 patients with Gustilo grade IIIB/C open fractures received an antibiotic cement-coated locking plate as a temporary internal fixator during initial surgery. Thorough debridement and temporary internal fixation were performed with a 3.5-mm system antibiotic cement-coated locking plate. Ten patients required free bone fragment removal, followed by bone cement packing. The final stage involved internal fixation and wound repair with a free anterolateral thigh flap. Clinical and imaging results were retrospectively analysed. The repair time ranged 1-7 days. All flaps survived. Two patients experienced wound infection, and one developed severe bone infection 3 months after three-stage bone graft surgery. Autologous cancellous bone grafting was performed on 10 patients with bone defects 6 weeks after surgery. Bone union was universally achieved after 1 year. This method proved safe and effective, successfully repairing Grade III open fractures of the lower extremity 1-7 days post-treatment.

[Effects of isopsoralen on tibial fracture and vascular healing in mice].

OBJECTIVE: To explore effects of isopsoralen (ISO) with different doses on fracture and vascular healing in mice. METHODS: Sixty 2-month-old male C57BL/6 mices with body mass of (20±2) g were selected and divided into 4 groups by random number table method:model group (model), low dose group (isopsoralen-low dose, ISO-L), medium dose group (isopsoralen-medium dose, ISO-M) and high dose group (isopsoralen-high dose, ISO-H), with 15 animals in each group. The right tibial fracture model was established. After operation, ISO-L group, ISO-M group and ISO-H group were given ISO concentration of 10 mg·kg-1, 20 mg·kg-1 and 40 mg·kg-1, respectively. Model group was given same volume of normal saline once a day for 28 days. Weighed once a week. X-ray was performed on 7, 14, 21 and 28 days, respectively, and modified I.R. Garrett scoring method was used to evaluate callus growth. After 28 days, the main organs were stripped and weighed, and organ coefficients were calculated. Hematoxylin eosin staining (HE staining) was performed on the organs to observe whether there were pathological structural changes. Micro-computed tomography (Micro-CT) was used to scan fracture area and conduct three-dimensional reconstruction to obtain the effect map, and quantify bone volume fraction (bone volume/total volume, BV/TV). After decalcification, the tibia was embedded in paraffin wax and sectioned. The healing and shape of fracture end were observed by HE staining and ferruxin solid green staining. The right tibia was removed and decalcified after intravascular infusion of Microfil contrast agent. Micro-CT was used to scan the callus microvessels in the fracture area, and the vascular volume fraction and vessel diameter were quantified. RESULTS: After 28 days of administration, there was no significant difference in body mass and organ coefficient among all groups (P>0.05), and no significant pathological changes were found in HE staining of organs. The results of X-ray and improved I.R. Garrett score showed that ISO-M group was higher than that of Model group at 28 days (P<0.05). Scores of ISO-H group at 14, 21 and 28 days were higher than those of the other 3 groups (P<0.05). Micro-CT results showed intracavitary callus in ISO-M group was significantly reduced, which was lower than that in Model group (P<0.05), most of the callus in ISO-H group were subsided, and BV/TV in ISO-H group was lower than that in the other 3 groups (P<0.05). The results of HE staining and ferrubens solid green staining showed fracture area of ISO-H group was closed, continuous laminar bone had appeared, and the fracture healing process was higher than that of other groups. Angiographic results showed vascular volume fraction in ISO-H and ISO-M groups was higher than that in Model and ISO-L groups (P<0.05), and the vascular diameter in ISO-H and ISO-M groups was higher than that in Model and ISO-L groups (P<0.05). CONCLUSION: In the concentration range of 10-40 mg·kg-1, ISO has no obvious toxic and side effects, and could improve bone microstructure, promote formation of callus microvessels, and accelerate healing of fracture ends in a concentration-dependent manner.

Estrogen deficiency impedes fracture healing despite eliminating the excessive absorption of the posterior callus in a semi-fixed distal tibial fracture mouse model.

BACKGROUND: Treatment of distal tibial fractures is a challenge due to their specific anatomical location. However, there is no appropriate mouse model to simulate a clinical distal tibial fracture for basic research. The aim of this investigation was to evaluate the feasibility of simulating a clinical fracture of the distal tibia of mice and to investigate the effect of ovariectomy (OVX)-induced osteoporosis on fracture healing in this model. METHODS: Sixty female 8-week-old C57BL/6 mice were randomly divided into two groups, either sham or OVX. A semi-fixation distal tibia fracture was established in the right tibia after 8 weeks of OVX. The right tibias were collected at 7, 14, 21, and 28 days post fracture. RESULTS: In the semi-fixation distal tibia fracture model, the posterior callus in the sham group showed excessive bone resorption and lower bone mass phenotype compared with the anterior site; a similar trend was not found in the OVX group. At 28 days post fracture, the posterior callus was more mineralized than the anterior callus in the OVX group. Although the fracture healing of the sham group showed a special phenotype in this mode, the progress and quality of fracture healing were still better than those of the OVX group. CONCLUSION: A semi-fixed distal tibial closed fracture mouse model was successfully established. In this model, excess bone resorption of the posterior callus impaired normal fracture healing, but not in OVX-induced osteoporotic bone. Although the stress shielding effect was not observed in the OVX group, impaired bone healing caused by OVX was still present. Our results suggest that this fracture model may have potential for studies on distal tibial fractures and stress shielding.

Effects of repeated intravenous doses of tranexamic acid on closed tibial fracture healing: Experimental study based on the rat model.

OBJECTIVE: The aim of this study was to assess the effects of tranexamic acid on fracture healing in the rat tibia closed fracture model. METHODS: Sixty-four male Sprague-Dawley rats were included in this study, where closed fracture and intramedullary nailing were performed on their right tibial diaphyses. They were divided into 2 main groups, the experimental group, which was given weekly tranexamic acid injections, and the control group, which received no additional treatment. Eight rats from each group were sacrificed and evaluated for fracture healing at the first experimental group and control group, second experimental group and control group, third experimental group and control group, and fourth experimental group and control group weeks. Fracture healing was radiologically assessed according to the "Spencer Index" and "Lane and Sandhu Scoring System," and histologically evaluated according to the scoring system devised by Huo et al. Results: According to the Spencer Index, the mean union score was statistically significantly higher in the E3 group than in the third con- trol group (P = .014). Furthermore, the mean union score was statistically significantly higher in the fourth experimental group compared to the fourth control group (P=.047). According to the Lane and Sandhu Scoring System, only the mean union scores of the E3-4 groups were statistically significantly higher than the mean union scores of the C3-4 groups (P=.048). There was no histological difference between groups in terms of union, according to the criteria defined by Huo et al (P > .05). CONCLUSION: This study showed us that repeated intravenous administrations of tranexamic acid had no negative effect on fracture heal- ing in the rat tibia fracture model. Although tranexamic acid demonstrated better radiological healing in the late period, it had no effect on histological union.

Cannabidiol and Cannabigerol, Nonpsychotropic Cannabinoids, as Analgesics that Effectively Manage Bone Fracture Pain and Promote Healing in Mice.

Bone fractures are among the most prevalent musculoskeletal injuries, and pain management is an essential part of fracture treatment. Fractures heal through an early inflammatory phase, followed by repair and remodeling. Nonsteroidal anti-inflammatory drugs (NSAIDs) are not recommended for fracture pain control as they potently inhibit the inflammatory phase and, thus, impair the healing. Opioids do not provide a better alternative for several reasons, including abuse potential. Accordingly, there is an unmet clinical need for analgesics that effectively ameliorate postfracture pain without impeding the healing. Here, we investigated the analgesic efficacy of two nonpsychotropic cannabinoids, cannabidiol (CBD) and cannabigerol (CBG), in a mouse model for tibial fracture. Mice with fractured tibiae exhibited increased sensitivity to mechanical, cold, and hot stimuli. Both CBD and CBG normalized pain sensitivity to all tested stimuli, and their analgesic effects were comparable to those of the NSAIDs. Interestingly, CBD and CBG promoted bone healing via multiple mechanisms during the early and late phases. During the early inflammatory phase, both cannabinoids increased the abundance of periosteal bone progenitors in the healing hematoma and promoted the osteogenic commitment of these progenitors. During the later phases of healing, CBD and CBG accelerated the fibrocartilaginous callus mineralization and enhanced the viability and proliferation of bone and bone-marrow cells. These effects culminated in higher bone volume fraction, higher bone mineral density, and improved mechanical quality of the newly formed bone. Together, our data suggest CBD and CBG as therapeutic agents that can replace NSAIDs in managing postfracture pain as both cannabinoids exert potent analgesic effects and, at the same time, promote bone healing. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Morphological and biomechanical effects of vitamin K2 on fracture healing: An animal study on the rat tibia fracture model.

OBJECTIVE: The aim of this study was to evaluate the effects of vitamin K2 on fracture healing. METHODS: Twenty-four 6-week-old male Wistar albino rats that had open tibia fractures induced were included in this study. They were divided into 2 groups of 12, a group that had vitamin K2 administered over 30 consecutive days and a control group. After 30 days, the rats were sacrificed, and from each group, 6 tibiae were selected for biomechanical testing to examine the mechanical strength of the callus tissue using the Instron 3-point bending test and 6 tibiae were selected for histological analysis to examine the density and organization of callus tissue using Allen's grading system and Huo et al's grading system. Furthermore, weekly x-rays were taken to evaluate bone union described by Lane and Sandhu, and osteocalcin, procollagen I N-terminal propeptide, and procollagen I C-terminal propeptide were examined in blood samples taken by intracardiac puncture during sacrification. RESULTS: Breaking force (P = .047), breaking time (P = .019), stiffness (P = .039), fracture strength (P = .041), and Young's modulus (P = .032) showed a statistically significant increase in the K2 group. Procollagen I C-terminal propeptide (P = .024), procollagen I N-terminal propeptide (.047), and osteocalcin (.048) levels were significantly higher in the K2 group compared to the control group. Furthermore, 3rd-week x-rays showed higher bone union scores according to the Lane and Sandhu method in the K2 group (P = .014). However, the histological grading systems of Allen and Huo et al did not show statistically significant differences between groups (P = .086, P = .07, respectively). CONCLUSION: In light of these findings, it could be concluded that vitamin K2 has a significant positive effect on fracture healing.

Antibiotic cement-coated rigid locked nails in infected femoral and tibial nonunion. Reoperation rates of commercial versus custom-made nails.

INTRODUCTION: The objective of this study is to assess bone union, infection control, and reoperation rates in a series of patients with infected femoral or tibial nonunion treated with antibiotic-cement-coated rigid nails and to compare the results obtained with custom-made nails versus commercial nails. METHODS: We retrospectively analyzed a series of consecutive patients with infected nonunion of the femur or the tibia treated with antibiotic-cement-coated rigid nails between January 2010 and 2020. We assessed patients' distinctive characteristics, initial injury, type of nail used (custom-made nail with vancomycin or commercial nail with gentamicin), success rate (bone union + infection control), reoperation rate, and failure rate. Comparative analyses were conducted between reoperated and non-reoperated patients regarding the type of nail used. A multivariate regression analysis was performed to assess the risk variables that impacted reoperation rates. RESULTS: We included 54 patients with 22 (40.74%) infected femoral nonunions and 32 (59.25%) tibial nonunions, who were treated with 38 (70.37%) custom-made antibiotic-cement coated nails and 16 (29.62%) commercial nails. Bone union and infection control were achieved in 51 (94.44%) cases. The reoperation rate was 40.74% (n = 22), and the failure rate was 5.55% (n = 3). The use of custom-made nails was associated with a higher risk of reoperation (Odds Ratio 4.71; 95% Confidence Interval 1.10 - 20.17; p = 0.036). CONCLUSION: Antibiotic-cement-coated nails reached a 94.44% success rate. Nails manufactured in the OR coated with vancomycin cement were associated with a higher risk of reoperation than commercial nails loaded with gentamicin cement. LEVEL OF EVIDENCE: III comparative, observational, non-randomized.

Irisin Modulates Inflammatory, Angiogenic, and Osteogenic Factors during Fracture Healing.

Bone fractures are a widespread clinical event due to accidental falls and trauma or bone fragility; they also occur in association with various diseases and are common with aging. In the search for new therapeutic strategies, a crucial link between irisin and bone fractures has recently emerged. To explore this issue, we subjected 8-week-old C57BL/6 male mice to tibial fracture, and then we treated them with intra-peritoneal injection of r-Irisin (100 µg/kg/weekly) or vehicle as control. At day 10 post fracture, histological analysis showed a significant reduced expression of inflammatory cytokines as tumor necrosis factor-alpha (TNFα) (p = 0.004) and macrophage inflammatory protein-alpha (MIP-1α) (p = 0.015) in the cartilaginous callus of irisin-treated mice compared to controls, supporting irisin's anti-inflammatory role. We also found increased expressions of the pro-angiogenic molecule vascular endothelial growth factor (VEGF) (p = 0.002) and the metalloproteinase MMP-13 (p = 0.0006) in the irisin-treated mice compared to the vehicle ones, suggesting a myokine involvement in angiogenesis and cartilage matrix degradation processes. Moreover, the bone morphogenetic protein (BMP2) expression was also upregulated (p = 0.002). Taken together, our findings suggest that irisin can contribute to fracture repair by reducing inflammation and promoting vessel invasion, matrix degradation, and bone formation, supporting its possible role as a novel molecule for fracture treatment.

Application of Bayesian Methods to Help Interpret the VANCO Trial Results.

OBJECTIVE: To determine whether a Bayesian analysis changes the results of the VANCO trial. DESIGN: A secondary analysis of a randomized clinical trial using Bayesian methods. SETTING: Thirty-six US trauma centers. PATIENTS: Patients ages 18-80 years with a tibial plateau or pilon fracture deemed high risk of infection and definitively treated with plate and screw fixation. INTERVENTION: Patients were randomly allocated to receive 1000 mg of intrawound vancomycin powder at their definitive fixation or to a control group that received no topical antibiotics. MAIN OUTCOME MEASUREMENTS: A deep surgical site infection requiring operative treatment within 6 months of definitive fixation. Secondary outcomes included gram-positive and gram-negative-only deep surgical site infections. RESULTS: Of the 980 patients randomized, 874 (89%) had at least 140 days of follow-up and were included in this Bayesian analysis. The estimated probability that intrawound vancomycin powder reduces the risk of a deep surgical site infection is >98% [relative risk (RR), 0.66; 95% credible interval (CrI), 0.46-0.98]. There is a >99% chance intrawound vancomycin powder reduces gram-positive infections and an 80% chance the magnitude of this risk reduction exceeds 35% (RR, 0.52; 95% CrI, 0.33-0.84) exists. It is unlikely (44%) that intrawound vancomycin powder prevents gram-negative surgical site infections (RR, 1.06; 95% CrI, 0.48-2.45). CONCLUSIONS: There is a high probability (>98%) that intrawound vancomycin powder reduces deep surgical site infections in patients with tibial plateau or pilon fractures at high risk of infection and even more likely it reduces deep infections with gram-positive pathogens (>99%). LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Suplementación efectiva de vitamina D en pacientes con fractura tibial / Effective vitamin D supplementation in patients with tibial fracture

OBJETIVOS Determinar la prevalencia de déficit de vitamina D, así como evaluar la seguridad y efectividad de un nuevo método de carga con colecalciferol en pacientes adultos con fractura de tibia. MATERIALES Y MÉTODOS Se reclutaron a 56 pacientes consecutivos con edades entre 18 y 65 años con fractura de tibia ingresados en nuestro hospital durante 1 año. Se determinó el nivel de 25-hidroxivitamina D ([25(OH)-D]) al ingreso y tras suplementación con 100.000 UI semanales de colecalciferol, durante 3 o 5 semanas, en casos de insuficiencia ([25(OH)-D] entre 20 ng/mL y 29,9 ng/mL) o deficiencia ([25(OH)-D] < 20 ng/mL), respectivamente. Se determinó la prevalencia de hipovitaminosis D, el porcentaje de normalización de [25(OH)-D], y los efectos adversos. RESULTADOS Se evaluaron 56 pacientes; 98,2% presentó hipovitaminosis D, y 28 (73,7%) y 10 (26,3%) presentaron déficit e insuficiencia, respectivamente. Tras la suplementación, 92,1% alcanzaron niveles [25(OH)-D] normales. Ningún paciente presentó efectos adversos. DISCUSIÓN La prevalencia de deficiencia de vitamina D en nuestra población fue mayor a la reportada en la literatura. Comprobamos que un esquema de suplementación en altas dosis de vitamina D es seguro, y más efectivo que los previamente recomendados. Este esquema de suplementación puede ser implementado en futuros estudios randomizados. CONCLUSIÓN La prevalencia de hipovitaminosis D en pacientes adultos chilenos con fractura de tibia fue alta (98,2%). El esquema de suplementación con vitamina D propuesto fue efectivo y seguro.

OBJETIVOS Determinar la prevalencia de déficit de vitamina D, así como evaluar la seguridad y efectividad de un nuevo método de carga con colecalciferol en pacientes adultos con fractura de tibia. MATERIALES Y MÉTODOS Se reclutaron a 56 pacientes consecutivos con edades entre 18 y 65 años con fractura de tibia ingresados en nuestro hospital durante 1 año. Se determinó el nivel de 25-hidroxivitamina D ([25(OH)-D]) al ingreso y tras suplementación con 100.000 UI semanales de colecalciferol, durante 3 o 5 semanas, en casos de insuficiencia ([25(OH)-D] entre 20 ng/mL y 29,9 ng/mL) o deficiencia ([25(OH)-D] < 20 ng/mL), respectivamente. Se determinó la prevalencia de hipovitaminosis D, el porcentaje de normalización de [25(OH)-D], y los efectos adversos. RESULTADOS Se evaluaron 56 pacientes; 98,2% presentó hipovitaminosis D, y 28 (73,7%) y 10 (26,3%) presentaron déficit e insuficiencia, respectivamente. Tras la suplementación, 92,1% alcanzaron niveles [25(OH)-D] normales. Ningún paciente presentó efectos adversos. DISCUSIÓN La prevalencia de deficiencia de vitamina D en nuestra población fue mayor a la reportada en la literatura. Comprobamos que un esquema de suplementación en altas dosis de vitamina D es seguro, y más efectivo que los previamente recomendados. Este esquema de suplementación puede ser implementado en futuros estudios randomizados. CONCLUSIÓN La prevalencia de hipovitaminosis D en pacientes adultos chilenos con fractura de tibia fue alta (98,2%). El esquema de suplementación con vitamina D propuesto fue efectivo y seguro.

Deer antler extract promotes tibia fracture healing in mice by activating BMP-2/SMAD4 signaling pathway.

BACKGROUND: Deer antler is a traditional Chinese medicine with the function of tonifying kidney and strengthening bone, which is often used to treat orthopedic diseases. METHODS: Eight-week-old C57BL/6 mice were used as the fixation model of open tibial fracture with intramedullary nail. The mice were treated with deer antler extract (DAE) or PBS by oral gavage once daily. The tibial fracture samples were collected and performed to the tissue analysis, including X-ray, micro-CT, histology, qRT-PCR, immunohistochemistry. MC3T3-E1 cells were used to detect the effect of deer antler extract on ability of cell proliferation and migration by CCK-8 assay and cell scratch test. RESULTS: Imaging and micro-CT showed that DAE could promote the healing of tibial fracture in mice, and histological analysis showed that DAE could promote the transformation of cartilage callus to bone callus in fracture area. The results of qRT-PCR and immunohistochemistry showed that DAE could promote intrachondral ossification in fracture zone and the mechanism of promoting fracture healing may be related to the activation of BMP-2/SMAD4 signaling pathway. In the cytological experiment of DAE, it can be found that DAE promoted the proliferation of MC3T3-E1 cells and the migration of MC3T3-E1 cells at a certain concentration, which is also related to the promotion of fracture healing by DAE. CONCLUSION: DAE can promote fracture healing by activating BMP-2/SMAD4 signaling pathway. DAE has the potential to be used in clinic as an important means of promoting fracture healing.

Acute shortening and re-lengthening versus antibiotic calcium sulfate-loaded bone transport for the management of large segmental tibial defects after trauma.

BACKGROUND: The purpose of this paper was to compare the clinical effects of acute shortening and re-lengthening (ASR) technique with antibiotic calcium sulfate-loaded bone transport (ACSBT) technique for the management of large segmental tibial defects after trauma. METHODS: In this retrospective study, 68 patients with large segmental tibial defects were included and completely followed. The bone loss was 3-10 cm. ASR group included 32 patients, while ACSBT group contained 36. There was no significant difference in demographic information between the two groups. The external fixation time (EFT) and external fixation index (EFI) were compared. Bone defect healing and limb functions were evaluated according to the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria. Complications were compared by Paley classification. RESULTS: The mean EFT was 9.2 ± 1.8 months in ASR group and 10.1 ± 2.0 months in ACSBT group, respectively. The mean EFI was 1.5 ± 0.2 month/cm and 1.4 ± 0.3 month/cm. According to the ASAMI criteria, in ASR group bone defect healing was excellent in 22 cases, good in 7 cases and fair in 3 cases. In ACSBT group, it was excellent in 23 cases, good in 11 cases and fair in 2 cases. In ASR group, the limb function was excellent in 15 cases, good in 7 cases and fair in 10 cases, while it was excellent in 14 cases, good in 9 cases and fair in 13 cases with ACSBT group. There was no significant difference in EFI, bone defect healing and limb functions between the two groups (p > 0.05). The mean number of complications per patient in ACSBT group was significantly lower than that in ASR group (p < 0.05). CONCLUSION: Both techniques can be successfully used for the management of large segmental tibial defects after trauma. There was no significant difference in EFI, limb functions and bone defect healing between the two groups. Compared with ASR group, the complication incidence in ACSBT group was lower, especially the infection-related complications. Therefore, for patients with large segmental bone defects caused by infection or osteomyelitis, ACSBT technique could be the first choice.

Proteasome inhibition-enhanced fracture repair is associated with increased mesenchymal progenitor cells in mice.

The ubiquitin/proteasome system controls the stability of Runx2 and JunB, proteins essential for differentiation of mesenchymal progenitor/stem cells (MPCs) to osteoblasts. Local administration of proteasome inhibitor enhances bone fracture healing by accelerating endochondral ossification. However, if a short-term administration of proteasome inhibitor enhances fracture repair and potential mechanisms involved have yet to be exploited. We hypothesize that injury activates the ubiquitin/proteasome system in callus, leading to elevated protein ubiquitination and degradation, decreased MPCs, and impaired fracture healing, which can be prevented by a short-term of proteasome inhibition. We used a tibial fracture model in Nestin-GFP reporter mice, in which a subgroup of MPCs are labeled by Nestin-GFP, to test our hypothesis. We found increased expression of ubiquitin E3 ligases and ubiquitinated proteins in callus tissues at the early phase of fracture repair. Proteasome inhibitor Bortezomib, given soon after fracture, enhanced fracture repair, which is accompanied by increased callus Nestin-GFP+ cells and their proliferation, and the expression of osteoblast-associated genes and Runx2 and JunB proteins. Thus, early treatment of fractures with Bortezomib could enhance the fracture repair by increasing the number and proliferation of MPCs.

Outcomes of Various Antibiotic Cement-Coated Intramedullary Implants on the Treatment of Long Bone Septic Nonunion.

OBJECTIVE: To determine the effectiveness of various types of antibiotic-coated intramedullary implants in the treatment of septic long bone nonunion. DESIGN: Retrospective chart review. SETTING: Level 1 trauma center. PARTICIPANTS: Forty-one patients with septic long bone nonunion treated with an antibiotic cement-coated intramedullary implant. INTERVENTION: Surgical debridement and placement of a type of antibiotic-coated intramedullary implant. MAIN OUTCOME MEASUREMENTS: Union and need for reoperation. RESULTS: At an average 27-month follow-up (6-104), 27 patients (66%) had a modified radiographic union score of the tibia of 11.5 or greater, 12 patients (29%) a score lower than 11.5, and 2 patients (5%) underwent subsequent amputation. Six patients underwent no further surgical procedures after the index operation. Patients treated with a rigid, locked antibiotic nail achieved earlier weight-bearing (P = 0.001), less frequently required autograft (P = 0.005), and underwent fewer subsequent procedures (average 0.38 vs. 3.60, P = 0.004) than those treated with flexible core antibiotic rods. CONCLUSIONS: Antibiotic-coated intramedullary implants are successful in the treatment of septic nonunions in long bones. In our cohort, rigid, statically locked nails allowed faster rehabilitation, decreased the need for autograft, and decreased the number of additional surgical procedures. Further study is needed to confirm these findings. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Analgesic effects of a 5-HT3 receptor antagonist in an animal model of complex regional pain syndrome.

OBJECTIVE: Complex regional pain syndrome (CRPS) is caused by injuries from fracture after trauma and orthopaedic surgical procedures in the hind limbs. The symptoms of CRPS include warmth, pain, allodynia, and hyperalgesia. It is known that 5-hydroxytryptamine 3 (5-HT3) receptors contribute to hyperalgesia, but their role has not yet been fully elucidated. This study investigated the mechanism of pain relief when a 5-HT3 receptor antagonist was administered in a CRPS animal model. MATERIALS AND METHODS: To establish a CRPS animal model, 10-week-old Sprague-Dawley rats were used in the experiment. On the fourth week post tibial fracture surgery, we performed the von Frey test to measure mechanical allodynia. After performing behavioural tests, we collected blood and tissue samples after sacrificing the animals. Enzyme-linked immunosorbent assay and western blot were also performed. RESULTS: The experimental tibia fracture model-induced CRPS animals elicited increased 5-HT3 receptor expression, and the 5-HT transporter was decreased in the brain stem after 4 weeks of surgical intervention. Additionally, in CRPS-induced animals, both the concentration of substance P and the level of interleukin 6 were increased peripherally and centrally. Treatment with the 5-HT3 receptor antagonist, ramosetron, exerted an analgesic effect in the paw withdrawal test and was dependent on the attenuation of the 5-HT3 receptor population with inflammatory pain mediators. CONCLUSIONS: These data suggest that treatment with the 5-HT3 receptor antagonist, ramosetron, in experimental CRPS animal models alleviated pain-related behaviours and may be a new therapeutic option or potential therapeutic agent for patients with CRPS.

Intra-medullary antibiotics perfusion (iMAP) for the control of fracture-related infection early after osteosynthesis.

PURPOSE: In our hospital, cases of bone and soft tissue infections have been treated with continuous local antibiotics perfusion that allows for continuous circulation of antibiotics throughout the infected lesion. We termed this treatment "intramedullary antibiotics perfusion (iMAP)" for bone infection such as fracture-related infection (FRI) and "intrasoft tissue antibiotics perfusion" for soft tissue infection. Many cases are treated with both modalities. To introduce iMAP, this study focused on the patients with FRI treated with iMAP and reviewed their treatment outcomes. METHODS: We included 10 patients with FRI treated with iMAP between 2004 and 2017. The iMAP needles were inserted near the infected lesion, and an aminoglycoside antimicrobial was continuously administered. Patient characteristics, pathogenic bacteria, administered antibiotics, duration of administration, concentrations of antibiotics in blood and leachate fluid, fracture union rate, implant retention rate, and complications were studied. RESULTS: The mean age of patients was 59.9 years, and the mean follow-up period was 2.5 years. Affected bones were the tibia (n = 8), humerus (n = 1), and fibula (n = 1). Deep infections developed on average 29.9 days after osteosynthesis. Pathogenic bacteria were methicillin-susceptible Staphylococcus aureus (n = 6), methicillin-resistant S. aureus (n = 2), and unknown (n = 2). Average iMAP duration was 17.1 days. In all patients, infection was eradicated while preserving the implants, and fracture union was achieved without complications. CONCLUSION: iMAP is a novel local drug delivery system allowing high concentrations of antibiotics to be administered without complications and is useful in the treatment of FRI.

Effects of icariin on the fracture healing in young and old rats and its mechanism.

CONTEXT: Icariin has attracted increasing attention because of its wide variety of pharmacological effects. OBJECTIVE: This study investigates whether icariin could promote fracture healing in young and old rats and its mechanisms. MATERIALS AND METHODS: A Wistar rat model for the tibia fracture in relatively young and old rats, respectively, was established. The rats were divided into four groups: model group, L-icariin (50 mg/kg icariin), M-icariin (100 mg/kg icariin) and H-icariin (200 mg/kg icariin), and intragastric administration of icariin was performed for 10 days or 20 days. In addition, isolated and cultured rat bone mesenchymal stem cells (rBMSCs) from young and old rats were cultured with 5% and 20% of icariin-containing serum, respectively, then cell viability and alkaline phosphatase (ALP) activity were measured. RESULTS: Icariin administration induced the expression of Runx2, Osterix, BMP-2, p-Smad5 and osteocalcin secretion (young rats: model: 2.50 ± 0.71; L-icariin: 10.10 ± 1.55; M-icariin: 24.95 ± 2.19; H-icariin: 36.80 ± 2.26; old rats: model: 1.55 ± 0.49; L-icariin:6.55 ± 0.50; M-icariin: 15.00 ± 0.85; H-icariin:20.50 ± 2.27) at the fracture site, and increased the levels of bone formation markers (OC, BAP, NTX-1 and CTX-1) in a dose-dependent manner. In vitro, icariin treatment promoted rBMSC viability, increased ALP activity and the expression of BMP-2/Smad5/Runx2 pathway proteins. DISCUSSION AND CONCLUSIONS: Icariin may accelerate fracture healing by activating the BMP-2/Smad5/Runx2 pathway in relatively young and old rats. The research on the mechanism of icariin to promote fracture healing can provide a theoretical basis for the clinical application and promotion of icariin.

Antibiotic calcium sulfate-loaded hybrid transport versus traditional Ilizarov bone transport in the treatment of large tibial defects after trauma.

BACKGROUND: The purpose of this study was to compare the clinical effects of antibiotic calcium sulfate-loaded hybrid transport (ACSLHT) and traditional Ilizarov bone transport (TIBT) in the treatment of large tibial defects after trauma. METHODS: Eighty-five patients with large tibial defects after trauma were selected for retrospective study. The range of tibial defects was 6-22 cm. After thorough debridement and infection controlled, bone transport technique was used to reconstruct tibial defects. Forty-four patients were treated with ACSLHT technique (the ACSLHT group), while the other 41 were treated with TIBT technique (the TIBT group). Time in external fixator was evaluated by EFI score. Enneking score was used to evaluate limb functions. SAS score was used to evaluate postoperative anxiety status. In addition, complication incidence was compared, including axis deviation, docking site nonunion, infection recurrence and so on. RESULTS: There was no significant difference in preoperative general data between ACSLHT and TIBT group. EFI score in ACSLHT and TIBT group was 0.6 ± 0.1 cm/month and 1.7 ± 0.3 cm/month, respectively (P < 0.05). Enneking score of ACSLHT and TIBT group was 86.5% and 75.1% (P < 0.05). SAS score of ACSLHT group was significantly lower than that of TIBT group (P < 0.05). Complication incidence in ACSLHT group was significantly lower than that in TIBT group (P < 0.05). CONCLUSIONS: Compared with TIBT group, ACSLHT group had shorter time in external fixator, better limb functions, lower postoperative anxiety score and lower complication incidence which is worth of clinical promotion.

Single-Stage Treatment of Fracture-related Infections.

SUMMARY: Fracture-related infections (FRIs) remain a significant problem. Many approach FRI cases in a staged fashion, focusing on infection eradication initially and fracture union during subsequent procedures. The literature quotes high success rates with this strategy. However, associated patient morbidity and economic impact are noteworthy. A single-stage FRI treatment, using an antibiotic-coated locked intramedullary nail, also exists. This video details low-cost, antibiotic-coated locked intramedullary nail fabrication in the operating room alongside preliminary results using this technique for acute FRI and septic nonunion treatment.

Type II collagen from squid cartilage mediated myogenic IGF-I and irisin to activate the Ihh/PThrp and Wnt/ß-catenin pathways to promote fracture healing in mice.

Fractures are the most common large-organ, traumatic injury in humans. The fracture healing stage includes the inflammatory stage (0-5d), cartilage callus stage (5-14d) and hard callus stage (14-21d). All mice underwent open tibial fracture surgery and were treated with saline, Glu or SCII for 21d. Calluses were harvested 5d, 10d and 21d after fracture. Compared with the model group, SCII significantly decreased TNF-α and increased aggrecan serum levels by 5d. H&E results showed that fibrous calluses were already formed in the SCII group and that chondrocytes had begun to proliferate. By 10d, the chondrocytes in the SCII group became hypertrophic and mineralized, and the serum TGF-ß and Col-Iα levels were significantly increased, which indicated that the mice with SCII treatment rapidly passed the cartilage repair period and new bone formation was accelerated. Skeletal muscle repaired bones through muscle paracrine factors. IGF-1 and irisin are the two major secretory cytokines. The results showed that the content of muscle homogenate IGF-1 in the SCII group reached the peak at 10d, followed by the up-regulation of Ihh, Patched, Gli1 and Col10α in the callus through the bone surface receptor IGF-1R. Besides, SCII also significantly elevated the muscle irisin level (10 and 21d), and then increased Wnt10b, LRP5, ß-catenin and Runx2 expression in the callus by receptor αVß5. These results suggest that SCII can accelerate the process of endochondral osteogenesis and promote fracture healing through activating the Ihh/PThrp and Wnt/ß-catenin pathways by regulating muscle paracrine factors. To our knowledge, this is the first study to investigate the effect of marine-derived collagen on fracture healing. This study may provide a theoretical basis for the high-value application of the laryngeal cartilage of squid in the future.