New augmented reality remote for virtual guidance and education of fracture surgery: a retrospective, non-inferiority, multicenter cohort study.

BACKGROUND: The demand for telesurgery is rapidly increasing. Augmented reality (AR) remote surgery is a promising alternative, fulfilling a worldwide need in fracture surgery. However, previous AR endoscopic and Google Glass remotes remain unsuitable for fracture surgery, and the application of remote fracture surgery has not been reported. We aimed to evaluated the safety and clinical effectiveness of a new AR remote in fracture surgery. MATERIALS AND METHODS: This retrospective non-inferiority cohort study was conducted at three centres. Between January 1, 2018, and March 31, 2022, 800 patients who underwent fracture surgery were eligible for participation. The study enrolled 551 patients with fractures (132 patellae, 128 elbows, 126 tibial plateaus, and 165 ankles) divided into an AR group (specialists used AR to remotely guide junior doctors to perform surgeries) and a traditional non-remote group (specialists performed the surgery themselves). RESULTS: Among 364 patients (182 per group) matched by propensity score, seven (3.8%) in the AR group and four (3%) in the non-remote group developed complications. The 0.005 risk difference (95% confidence interval: -0.033 to 0.044) was below the pre-defined non-inferiority margin of a 10% absolute increase. A similar distribution in the individual components of all complications was found between the groups. Hierarchical analysis following propensity score matching revealed no statistical difference between the two groups regarding functional results at 1-year follow-up, operative time, amount of bleeding, number of fluoroscopies, and injury surgery interval. A Likert scale questionnaire showed positive results (median scores: 4-5) for safety, efficiency, and education. CONCLUSION: This study is the first to report that AR remote surgery can be as safe and effective as that performed by a specialist in person for fracture surgery, even without the physical presence of a specialist, and is associated with improving the skills and increasing the confidence of junior surgeons. This technique is promising for remote fracture surgery and other open surgeries, offering a new strategy to address inadequate medical care in remote areas.

Does a Video-Based and 3D Animation Hybrid Learning System Improve Teaching Outcomes in Orthopedic Surgery? A Randomized Controlled Trial.

OBJECTIVE: This study aims to evaluate the instructional efficacy of a 3D Surgical Training System (3DSTS), which combines real surgical footage with high-definition 3D animations, against conventional surgical videos and textbooks in the context of orthopedic proximal humerus fracture surgeries. DESIGN: Before the experiment, 89 participants completed a pre-educational knowledge assessment. They were then randomized into 3 groups: the 3DSTS group (n = 30), the surgical video (SV) group (n = 29), and the textbook group (n = 30). After their respective teaching courses, all participants took a posteducational assessment and completed a perceived cognitive load test. The 3DSTS group also filled out a satisfaction survey. Once all assessments were finished, the SV and textbook groups were introduced to the 3DSTS course and subsequently completed a satisfaction survey. All statistical analyses were executed using IBM SPSS version 24 (IBM Corp., Armonk, NY). For data fitting normal distribution, we employed one-way analysis of variance (one-way ANOVA) and Tukey HSD tests, whereas, for non-normally distributed data, we used Kruskal-Wallis H tests and Dunn's tests. The significance level for all tests was set at p < 0.05. SETTING: Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, P. R. China. PARTICIPANTS: About 89 doctors who undergoing standardized residents training. RESULT: The initial assessment scores among the three groups were comparable, showing no significant statistical difference. Post-education revealed a marked difference in the scores, with the 3DSTS group outperforming both the SV and textbook groups. Specifically, the 3DSTS group exhibited statistically greater improvement in areas such as procedural steps, and specialized surgical techniques compared to the SV and textbook groups. During the 3DSTS teaching process, participants reported the least perceived cognitive load and expressed strong satisfaction, highlighting that the instructional materials are well-prepared, and considering this teaching method superior and more innovative than previous courses they had encountered. CONCLUSION: The 3D Surgical Training System, integrating real videos with 3D animations, significantly enhances orthopedic surgery education over conventional methods, providing improved comprehension, lower cognitive load, and standardized learning outcomes. Its efficacy and high participant satisfaction underscore its potential for broader adoption in surgical disciplines. This study is registered with ClinicalTrials. gov ID: ChiCTR2300074730.

An oxidized dextran-composite self-healing coated magnesium scaffold reduces apoptosis to induce bone regeneration.

Self-healing coatings have shown promise in controlling the degradation of scaffolds and addressing coating detachment issues. However, developing a self-healing coating for magnesium (Mg) possessing multiple biological functions in infectious environments remains a significant challenge. In this study, a self-healing coating was developed for magnesium scaffolds using oxidized dextran (OD), 3-aminopropyltriethoxysilane (APTES), and nano-hydroxyapatite (nHA) doped micro-arc oxidation (MHA), named OD-MHA/Mg. The results demonstrated that the OD-MHA coating effectively addresses coating detachment issues and controls the degradation of Mg in an infectious environment through self-healing mechanisms. Furthermore, the OD-MHA/Mg scaffold exhibits antibacterial, antioxidant, and anti-apoptotic properties, it also promotes bone repair by upregulating the expression of osteogenesis genes and proteins. The findings of this study indicate that the OD-MHA coated Mg scaffold possessing multiple biological functions presents a promising approach for addressing infectious bone defects. Additionally, the study showcases the potential of polysaccharides with multiple biological functions in facilitating tissue healing even in challenging environments.

Mobilization Efficiency of Granulocyte Colony-stimulating Factor and Stem Cell Factor to Bone Marrow Mononuclear Cells and Mechanisms / 华中科技大学学报（医学）（英德文版）

The mobilization efficiency of granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF) to bone marrow mononuclear cells (MNCs) in mice was observed,and the changes of CXCL12/CXCR4 signal were detected in order to find out the mobilization mechanism of stem cells.Kunming mice were randomly divided into two groups.The mice in treatment group were subjected to subcutaneous injection of G-CSF at a dose of 100 μg/kg and SCF at a dose of 25 μg/kg every day for 5 days,and those in control group were given isodose physiological saline.The MNCs were separated,counted and cultured,and the colony-forming unit-fibroblast (CFU-F) was evaluated.CD34+CXCR4+ MNCs were sorted by flow cytometry.The expression of CXCL12 protein in bone marrow extracellular fluid was detected by ELISA,and that of CXCL12 mRNA in bone marrow was measured by RT-PCR.The results showed that the counts of MNCs in peripheral blood and bone marrow were increased after administration of G-CSF/SCF (P＜0.01).The factors had a dramatic effect on the expansion capability of CFU-F (P＜0.05).Flow cytometric of bone marrow MNCs surface markers revealed that CD34+CXCR4+ cells accounted for 44.6%±8.7% of the total CD34+ MNCs.Moreover,G-CSF/SCF treatment induced a decrease in bone marrowCXCL12 mRNA that closely mirrored the fall in CXCL12 protein.In this study,it is evidenced that G-CSF/SCF can effectively induce MNCs mobilization by disrupting the balance of CXCL12/CXCR4 signaling pathway in the bone marrow and down-regulating the interaction of CXCL12/CXCR4.

Isolation of Subtype Spermatogonia in Juvenile Rats / 华中科技大学学报（医学）（英德文版）

The present study was aimed at finding an effective method to isolate and purify the subtype of type A spermatogonial stem cells (SSCs) in juvenile rats. Testes from 9-days-old rats were used to isolate germ cells by using two-step enzymatic digestion. The expression of c-kit in the testes of the rats was immunohistochemically detected. After isolation, cell suspension was enriched further by discontinuous density gradient centrifugation. Then type A1-A4 spermatogonia was isolated from the purified spermatogonia with c-kit as the marker by using fluorescence-activated cell sorting(FACS). Electron microscopy was used to observe their ultrastructure. Finally, highly purified and viable subtype of SSCs was obtained. Cells separation with discontinuous density gradient centrifugation significantly increased the concentration of c-kit positive cells [(18.65±1.69)% after the centrifugation versus (3.16±0.84)% before the centrifugation, P＜0.01]. Furthermore, the recovery and viability were also high [(65.9±1.24)% and (85.6±1.14)%]. It is concluded that FACS with c-kit as the marker in combination with discontinuous density gradient centrifugation can well enrich type A1-A4spermatogonia from the testes of 9-days-old rats.