Severe open tibiofibular fractures account for approximately 28.1% of all open fractures. Among them, Gustilo-Anderson type IIIB/C fractures present significant clinical challenges due to associated bone and soft tissue defects, high infection rates, and risk of amputation. Inadequate preoperative assessment may lead to suboptimal emergency surgical planning or intraoperative complications. Historically, external fixation was often preferred, but this approach has been associated with limitations such as restricted joint mobility, delayed bone union, joint stiffness, and disuse osteoporosis, resulting in poor functional recovery. With advancements of debridement techniques, standardization of antibiotic use, and popularization of early soft tissue coverage, early internal fixation has gained broader acceptance. Nevertheless, controversies persist regarding the choice of fixation method, timing of definitive fixation, use of reamed versus unreamed intramedullary nailing, and necessity of fibular fixation. To standardize the diagnosis and early management of severe open tibiofibular fractures, reduce complication rates, and improve functional recovery, the Society of Microsurgery of the Chinese Medical Association organized a panel of domestic experts to develop the Evidence-based guideline for the diagnosis and early fixation of severe open tibiofibular fractures ( version 2025), using evidence-based methodology. The guidelines provided 12 recommendations covering diagnostic and early fixation strategies of severe open tibiofibular fractures, aiming to provide clinicians with scientifically grounded and standardized guidance.

ObjectiveTo investigate the spontaneous premature cardiac aging in SHJH^hr mice. MethodsA comparative study was conducted between SHJH^hr mice (SHJH^hr group) and wild-type ICR mice (WT group) at different ages (10 and 24 weeks). Cardiac function was analyzed using a small animal in vivo ultrasound imaging system. After euthanasia, organs were collected and weighed to assess the extent of cardiac atrophy. Cardiac pathological damage was observed using hematoxylin-eosin (HE) staining. Cardiac fibrosis was analyzed using Masson staining. Myocardial cell area was analyzed after wheat germ agglutinin (WGA) staining. The activities of oxidative damage indicators in myocardial tissue, including superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT), as well as the content of 8-hydroxy-2'-deoxyguanosine (8-OHdG), were measured using enzyme-linked immunosorbent assay. Real-time fluorescence quantitative PCR was used to measure the mRNA expression levels of factors associated with inflammation, fibrosis, and oxidative stress. Colorimetric assay was used to measure malondialdehyde (MDA) levels. ResultsCompared to WT group mice of the same age, 10-week-old mice in the SHJH^hr group showed no significant differences in stroke volume (SV), ejection fraction (EF), fractional shortening (FS), or heart and lung weights. However, at 24 weeks of age, mice in the SHJH^hr group had significantly lower SV, EF, and FS values compared to mice of the same age in the WT group (P<0.05), with no significant change in lung weight but a significant reduction in heart weight (P<0.05). Histological analysis of heart tissue from 24-week-old mice revealed no significant difference in cardiac fibrosis levels between SHJH^hr and WT groups, but WGA staining showed a significant reduction in myocardial cell area in mice in the SHJH^hr group (P<0.05). PCR analysis revealed a significant downregulation of mRNA levels of oxidative stress factors Sod2, Gpx1, and Cat genes (P<0.05). Biochemical assays indicated significantly reduced activities of oxidative damage-related enzymes SOD, GPX, and CAT in myocardial tissue (P<0.05), while the levels of oxidative damage markers 8-OHdG and MDA significantly increased (P<0.05). ConclusionMice in the SHJH^hr group exhibit premature cardiac aging, which may be associated with oxidative stress damage in myocardial tissue.

Hand degloving injury represents one of the most severe forms of hand trauma, characterised by challenging treatment and a complex prognostic outcome. It is crucial to effectively utilise the degloved tissues in emergency or primary repair of a hand degloving injury. This consensus provides a comprehensive review of the existing literature on definition, classification, emergency assessment, debridement, judgment of skin viability, in situ repair of the degloved skin, and adjunctive treatment for degloving injury of hand. Based on conclusion of both domestic and international experiences, this expert consensus on the classification of hand degloving injury and the emergency repair with the avulsed skin is established, aiming to provide a guidance to surgeons on standardised treatment strategy and improve the management of hand degloving injury.

Severe open tibiofibular fractures account for approximately 28.1% of all open fractures. Among them, Gustilo-Anderson type IIIB/C fractures present significant clinical challenges due to associated bone and soft tissue defects, high infection rates, and risk of amputation. Inadequate preoperative assessment may lead to suboptimal emergency surgical planning or intraoperative complications. Historically, external fixation was often preferred, but this approach has been associated with limitations such as restricted joint mobility, delayed bone union, joint stiffness, and disuse osteoporosis, resulting in poor functional recovery. With advancements of debridement techniques, standardization of antibiotic use, and popularization of early soft tissue coverage, early internal fixation has gained broader acceptance. Nevertheless, controversies persist regarding the choice of fixation method, timing of definitive fixation, use of reamed versus unreamed intramedullary nailing, and necessity of fibular fixation. To standardize the diagnosis and early management of severe open tibiofibular fractures, reduce complication rates, and improve functional recovery, the Society of Microsurgery of the Chinese Medical Association organized a panel of domestic experts to develop the Evidence-based guideline for the diagnosis and early fixation of severe open tibiofibular fractures ( version 2025), using evidence-based methodology. The guidelines provided 12 recommendations covering diagnostic and early fixation strategies of severe open tibiofibular fractures, aiming to provide clinicians with scientifically grounded and standardized guidance.

Hand degloving injury represents one of the most severe forms of hand trauma, characterised by challenging treatment and a complex prognostic outcome. It is crucial to effectively utilise the degloved tissues in emergency or primary repair of a hand degloving injury. This consensus provides a comprehensive review of the existing literature on definition, classification, emergency assessment, debridement, judgment of skin viability, in situ repair of the degloved skin, and adjunctive treatment for degloving injury of hand. Based on conclusion of both domestic and international experiences, this expert consensus on the classification of hand degloving injury and the emergency repair with the avulsed skin is established, aiming to provide a guidance to surgeons on standardised treatment strategy and improve the management of hand degloving injury.

Objective:To investigate the therapeutic effect of exosomes derived from remote ischemic conditioning on neurological dysfunction after cardiopulmonary resuscitation in a rat model of cardiac arrest and the relationship with glycocalyx protection.Methods:Exosomes were isolated from the blood of healthy adult male Sprague-Dawley rats using ultracentrifugation after undergoing remote ischemic conditioning for use as intervention drugs. Nanoparticle tracking analysis technology was used for exosome detection. Thirty-six adult male Sprague-Dawley rats were randomly assigned to 3 groups ( n=12 each) :Sham group, Control group and Exosome group. Cardiac arrest was induced by asphyxia for 7 min in the Control and Exosome groups. Placebo or exosomes (1×10 10 Particles) were infused intravenously at 5 min after the rats had returned of spontaneous circulation. Neuropsychological deficit score (NDS), open field test, Y maze and Morris water maze were used to assess neurological outcomes. The levels of plasma Hyaluronic acid (HA) and syndecan-1 (Sdc-1) were detected by Elisa. The expression levels of matrix metalloproteinase-2/9 (MMP-2/9) in hippocampal CA1 region were detected by Western blot. Results:After undergoing remote ischemic conditioning, the plasma levels of exosomes were elevated in rats compared to normal rats. Compared with the control group, the behavioral experiment of rats in the exosomes group were significantly improved, as evidenced by an increase in horizontal locomotor distance (5.86±2.89 vs. 17.53±5.51, P< 0.05), an increase in the correct rate of spontaneous alternation (13.29±15.07 vs. 42.63±10.25, P< 0.05), and a shortening of avoidance latency (25.83±8.54 vs. 13.49±4.55, P< 0.05). Plasma HA and Sdc-1 levels were significantly lower 24 h after resuscitation (HA: 26.34±9.83 vs. 14.84±6.26, P< 0.05; Sdc-1: 0.05±0.03 vs. 0.02±0.02, P<0.05), along with significantly lower MMP-2/9 levels in hippocampal tissue. Conclusions:Exosomes extracted from the plasma of rats undergoing remote ischemic conditioning can improve neurological dysfunction after cardiac arrest in rats, and the mechanism may be related to the inhibition of metalloproteinases and the reduction of endothelial glycocalyx degradation.

Objective:To explore the effects of tensile force on vascular lumen formation in three-dimensional printed tissue.Methods:The experimental research method was used. Human umbilical vein endothelial cells (HUVECs) were extracted from discarded umbilical cord tissue of 3 healthy women (aged 22 to 35 years) who gave birth in the Department of Gynaecology and Obstetrics of Suzhou Ruihua Orthopaedic Hospital from September 2020 to May 2021. Human skin fibroblasts (HSFs) were extracted from discarded normal skin tissue of 10 male patients (aged 20 to 45 years) who underwent wound repair in the Department of Hand Surgery of Suzhou Ruihua Orthopaedic Hospital from September 2020 to September 2022. After identification of the two kinds of cells, the 4 th to 6 th passage of cells were taken for the follow-up experiments. HUVECs and HSFs were used as seed cells, and polycaprolactone, gelatin, hyaluronic acid, and fibrin were used as scaffold materials, and the three-dimensional printed vascularized tissue was created by three-dimensional bioprinting technology. The printed tissue with polycaprolactone scaffold of 6 and 10 mm spacing, and without polycaprolactone scaffold were set as 6 mm spacing polycaprolactone group, 10 mm spacing polycaprolactone group, and non-polycaprolactone group, respectively. After 4 days of culture, the printed tissue in 10 mm spacing polycaprolactone group was selected to detect the cell survival by cell viability detection kit, and the cell survival rate was calculated. After 14 days of culture, the printed tissue in three groups were taken, and the shape change of tissue was observed by naked eyes; immunofluorescence staining was performed to observe the arrangement of filamentous actin, and lumen diameter, total length, and number of branches of vessel in the tissue. The tissue with micro-spring structure in the above-mentioned three groups was designed, printed, and cultured for 9 days, and the tensile force applied in the printed tissue was measured according to the force-displacement curve. The number of samples was all 3 in the above experiments. Data were statistically analyzed with one-way analysis of variance and Tukey test. Results:After 4 days of culture, the cell survival rate in printed tissue in 10 mm spacing polycaprolactone group was (91.3±2.2)%. After 14 days of culture, the shape change of printed tissue in non-polycaprolactone group was not obvious, while the shape changes of printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group were obvious. After 14 days of culture, the arrangement of filamentous actin in the printed tissue in non-polycaprolactone group had no specific direction, while the arrangement of filamentous actin in the printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group had a specific direction. After 14 days of culture, The vascular lumen diameters of the printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group were (6.0±1.3) and (10.8±1.3) μm, respectively, which were significantly larger than 0 μm in non-polycaprolactone group ( P<0.05), and the vascular lumen diameter of printed tissue in 10 mm spacing polycaprolactone group was significantly larger than that in 6 mm spacing polycaprolactone group ( P<0.05); the total length and number of branches of blood vessel in the printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group were significantly shorter or less than those in non-polycaprolactone group ( P<0.05), and the total length and number of branches of blood vessel in the printed tissue in 10 mm spacing polycaprolactone group were significantly shorter or less than those in 6 mm spacing polycaprolactone group. After 9 days of culture, the tensile forces applied in the printed tissue in 6 mm spacing polycaprolactone group and 10 mm spacing polycaprolactone group were (2 340±59) and (4 284±538) μN, respectively, which were significantly higher than 0 μN in non-polycaprolactone group ( P<0.05), and the tensile force applied in the printed tissue in 10 mm spacing polycaprolactone group was significantly higher than that in 6 mm spacing polycaprolactone group ( P<0.05). Conclusions:The three-dimensional printed scaffold structure can exert different tensile force in the printed tissue, and the vascular lumen diameter of the printed tissue can be regulated by adjusting the tensile force.

Objective:To compare the clinical efficacy between robot-assisted and free-hand percutaneous cannulated screwing (PCS) in the treatment of femoral neck fractures in the middle-aged and young patients.Methods:A retrospective study was conducted to analyze the clinical data of 53 patients with femoral neck fracture who had been treated with PCS from May 2020 to May 2022 at Department of Traumatic Surgery, Maoming Hospital Affiliated to Southern Medical University. In the robot group of 25 patients subjected to robot-assisted PCS, there were 11 males and 14 females with an age of (48.2 ± 11.9) years; in the free-hand group of 28 patients subjected to free-hand PCS, there were 13 males and 15 females with an age of (48.5 ± 9.8) years. The 2 groups were compared in terms of operation time, intraoperative bleeding, intraoperative guide drills, intraoperative fluoroscopy frequency, fracture union time, Harris hip score at the last follow-up and postoperative complications. Postoperative imaging examination was performed to evaluate distribution accuracy of the cannulated screws in the femoral neck (deviation between the screws and the femoral neck axis, parallelism between the screws and distance between the screws and the neck cortex).Results:There was no statistically significant difference between the robot and free-hand groups in the general clinical data before operation, showing comparability ( P>0.05). The robot group showed significantly shorter operation time [(32.7 ± 4.8) min], significantly less intraoperative bleeding [(14.6 ± 4.8) mL], significantly less intraoperative guide drillings [(3.5 ± 0.7) times] and significantly less intraoperative fluoroscopy frequency [(7.9 ± 1.4) times] than the free-hand group [(56.9 ± 11.3) min, (27.0 ± 7.3) mL, (9.1 ± 1.8) times and (16.3 ± 6.0) times)] (all P<0.05). Postoperative imaging showed that the deviation between the screws and the femoral neck axis was 4.4° ± 1.1° on the anteroposterior X-ray film and 3.2° ± 0.8° on the lateral X-ray film, the parallelism between the screws 4.9° ± 0.8° on the anteroposterior X-ray film and 3.0° ± 0.7° on the lateral X-ray film, and the distance between the screws and the femoral neck cortex (10.4 ± 2.7) mm in the robot group, all significantly smaller than those in the free-hand group [10.5° ± 2.8°, 4.9° ± 1.1°, 12.1° ± 4.0°, 5.1° ± 1.3°, and (15.4 ± 3.2) mm] (all P<0.05). All the 53 patients were followed up for (22.2 ± 8.5) months. All fractures got united. The fracture union time in the robot group [(20.6 ± 4.6) weeks] was insignificantly shorter than that in the free-hand group [(23.7 ± 7.7) weeks] ( P>0.05). At the last follow-up, the Harris hip score in the robot group [(88.6 ± 5.6) points] was significantly higher than that in the free-hand group [(84.8 ± 6.3) points] ( P<0.05). Follow-ups revealed 2 cases of internal fixation loosening, 1 case of screw head cutting and 1 case of femoral head necrosis in the free-hand group but none of such complications in the robot group. Conclusion:In the treatment of femoral neck fractures in the middle-aged and young patients, compared with free-hand PCS, robot-assisted PCS shows advantages of shorter intraoperative time, less bleeding, less fluoroscopic radiation, higher accuracy of screw placement, a lower incidence of postoperative complications and better functional recovery of the hip joint.

ObjectiveTo introduce the Hr gene of spontaneously mutated SHJH^hr mice into BALB/cAShjh inbred mice with clear genetic background,and provide a basis for study on the molecular mechanism of Hr gene mutation-induced abnormal phenotype and the application of this model.Methods Using a backcross-intercross breeding method guided by phenotypic monitoring, mutant genes from SHJH^hr mice bred by spontaneous mutation were introduced into inbred BALB/cAShjh mice by homozygous mutation introgression, and the mice were bred into BALB/cA.Cg.SHJH^hr (abbreviated as C.Cg.SHJH^hr) mice after 10 generations. The genotypes of 90 single nucleotide polymorphism (SNP) detection sites were analyzed in C.Cg.SHJH^hr mice by multiplex PCR library construction followed by next generation sequencing. Then 14 biochemical locus marker genes were detected in C.Cg.SHJH^hr mice according to the method of GB/T 14927.1-2008. Finally, whole genome exon sequencing was utilized to detect the mutated genes in this mouse. ResultsFrom May 2018 to March 2022, a total of 10 generations of backcross-intercross were conducted to complete the construction of the C.Cg.SHJH^hr mouse line. Among the 90 SNPs loci detected, except for rs13484115 and rs13484116, all the other loci had the same genotype as the recipient mice BALB/cAShjh. The results of biochemical marker gene detection showed that all the 14 loci of the mouse were the same as those of the recipient mouse. Whole genome exon sequencing found that the mouse had 109 site mutations compared with the recipient mouse strain, including 71 synonymous mutations, 1 stopgain, 37 missense mutations, and 20 genes involved in protein sequence alterations (including the reported Hr gene). ConclusionC.Cg.SHJH^hr mice were created. Through exon sequencing and genetic analysis, three Hr mutated genes and associated mutated genes that mainly cause phenotypic variations were identified, which provides a basis for expanding the application of C.Cg.SHJH^hr mice in biomedical research.

Objective To measure and analyze biological characteristics and aging phenotype of SHJH^hr mice and provide basic data for the application of the mouse model in aging mechanisms research and antiaging drug development. MethodsWith ICR mice of the same age as control group, the body mass growth data of SHJH^hr mice at the age of 3 to 16 weeks, the reproduction ability of 1 to 4 fetuses and the life cycle of SHJH^hr mice were measured. Blood routine (30 items) and serum biochemical indexes (25 items) of 6-week-old SHJH^hr mice were measured. The venous blood of 8-week-old SHJH^hr mice was collected for flow cytometry analysis to determine the content of immune cells. The aging bone structure of the cancellous bone and bone mineral density of SHJH^hr mice aged 4, 8 and 26 weeks were measured by micro-CT. Histopathological changes of bone and joint of 8-week-old mice were observed. ResultsCompared with ICR mice, the female and male body mass of SHJH^hr mice were significantly lower at the age of 16 weeks (P < 0.05), and the reproductive performance of female mice was low (P < 0.01) or did not have normal reproductive capacity. The shortest survival time of SHJH^hr mice was 57 weeks and the longest was 71 weeks, which was shorter than those of normal ICR mice, showing obvious rapid aging phenomenon. At the same time, some physiological and biochemical indexes of blood and pathological changes of bone and cartilage tissues also showed the accelerated aging and abnormality of animal physiological functions. ConclusionSHJH^hr mice have some biological characteristics of rapid aging as well as some physiological and pathological changes caused by aging.