OBJECTIVE: To review and summarize the research progress on repairing segmental bone defects using three-dimensional (3D)-printed bone scaffolds combined with vascularized tissue flaps in recent years. METHODS: Relevant literature was reviewed to summarize the application of 3D printing technology in artificial bone scaffolds made from different biomaterials, as well as methods for repairing segmental bone defects by combining these scaffolds with various vascularized tissue flaps. RESULTS: The combination of 3D-printed artificial bone scaffolds with different vascularized tissue flaps has provided new strategies for repairing segmental bone defects. 3D-printed artificial bone scaffolds include 3D-printed polymer scaffolds, bio-ceramic scaffolds, and metal scaffolds. When these scaffolds of different materials are combined with vascularized tissue flaps ( e.g., omental flaps, fascial flaps, periosteal flaps, muscular flaps, and bone flaps), they provide blood supply to the inorganic artificial bone scaffolds. After implantation into the defect site, the scaffolds not only achieve structural filling and mechanical support for the bone defect area, but also promote osteogenesis and vascular regeneration. Additionally, the mechanical properties, porous structure, and biocompatibility of the 3D-printed scaffold materials are key factors influencing their osteogenic efficiency. Furthermore, loading the scaffolds with active components such as osteogenic cells and growth factors can synergistically enhance bone defect healing and vascularization processes. CONCLUSION The repair of segmental bone defects using 3D-printed artificial bone scaffolds combined with vascularized tissue flap transplantation integrates material science technologies with surgical therapeutic approaches, which will significantly improve the clinical treatment outcomes of segmental bone defect repair.
Printing, Three-Dimensional ; Tissue Scaffolds ; Humans ; Surgical Flaps/blood supply* ; Tissue Engineering/methods* ; Plastic Surgery Procedures/methods* ; Bone and Bones/surgery* ; Biocompatible Materials ; Bone Regeneration ; Bone Transplantation/methods* ; Bone Substitutes ; Osteogenesis

OBJECTIVE: To summarize the biomechanical research progress on different fixation methods in medial opening-wedge high tibial osteotomy (MOWHTO) and provide references for selecting appropriate fixation methods in clinical applications of MOWHTO for treating knee osteoarthritis (KOA). METHODS: Recent domestic and international literature on the biomechanical studies of MOWHTO fixation methods was reviewed to analyze the characteristics and biomechanical performance of various fixation techniques. RESULTS: The medial-specific osteotomy plate system has become the mainstream due to its high stiffness and stability, but issues such as soft tissue irritation and stress shielding remain. The use of filler blocks significantly enhances fixation stability and promotes bone healing when the osteotomy gap is large, reducing axial displacement by 73%-76% and decreasing plate stress by 90%. Auxiliary screws improve axial and torsional stability, particularly in cases with large correction angles, effectively preventing lateral hinge fractures. Alternative fixation methods like external fixators hold unique clinical value by minimizing soft tissue irritation and allowing postoperative adjustment. CONCLUSION There is currently no unified standard for selecting MOWHTO fixation methods. Clinical decisions should comprehensively consider factors such as bone quality, correction angle, and postoperative rehabilitation needs.
Humans ; Osteotomy/instrumentation* ; Biomechanical Phenomena ; Tibia/surgery* ; Bone Plates ; Osteoarthritis, Knee/surgery* ; Bone Screws ; External Fixators ; Knee Joint/surgery*

Objective To investigate the effects of three-dimensional(3D)screws and circular plates on the biomechanical stability of Sanders ABⅢ calcaneal fractures.Methods Calcaneal computed tomography(CT)and magnetic resonance imaging(MRI)data from a 26-year-old volunteer were collected to establish a 3D finite element model of Sanders ⅢAB calcaneal fracture fixed with 3D screws and circular plates.A longitudinal load of 700 N was applied to compare the variations in the stress,displacement of the bone block,and internal fixation in the different models.Results Under 700 N longitudinal loads,the maximum displacement of the bone block and the maximum stress of the bone block and internal fixation were concentrated at the intersection of the posterior talar articular plane internal fixation and fracture line.The overall displacements of the bone blocks in the 3D screw and circular plate models were similar.Compared with the circular plate model,the maximum and average stresses of the bone block and internal fixation in the 3D screw model were lower,and the displacement and stress changes of the 3D screw model were closer to those of the complete calcaneal bone model.Conclusions In the fixation of Sanders ⅢAB calcaneal fractures,both 3D screw and circular plate fixation method can provide good stability.The biomechanical properties of the 3D screws were better than those of the circular plates,which is consistent with the biomechanical characteristics.

In order to provide basic information for the utilization and development of famous classical formulas containing Bletillae Rhizoma， this article systematically analyzes the historical evolution of the name， origin， harvesting and processing of Bletillae Rhizoma by reviewing the ancient materia medica， prescription books， medical books and modern literature. The research results showed that Baiji（白及） was the main name， some scholars took Baiji（白芨） as its main name， and there were many other names such as Baiji（白给）， Baigen（白根）， Baiji（白苙）. The mainstream source of Bletillae Rhizoma was the tubers of Bletilla striata， and drying， large， white， solid， root-free and skin removed completely were the good quality standards. With the promotion of wild to cultivated medicinal materials， there were certain differences between their traits， and the quality evaluation indexes should be adjusted accordingly. The origin of records in the past dynasties was widely distributed， with Guizhou and Sichuan having high production and good quality in modern times. The harvesting period is mostly in spring and autumn， and harvested in autumn was better. The processing and processing technology is relatively simple， and it was used fresh or powdered in past dynasties， while it is mainly sliced for raw use in modern times. Based on the results， it is suggested that the tubers of Bletilla striata of Orchidaceae should be used in the famous classical formulas， and it should be uniformly written as Baiji（白及）. And if the original formula indicates the requirement of processing， it should be operated according to the requirement， if the requirement of processing is not indicated， it can be used in raw form as medicine.

BACKGROUND:The traditional view is that proximal fibular fractures do not require fixation.Others and our research suggest that the proximal fibular structure plays an important role in the stability of the posterolateral structure of the knee joint,and its mechanism of action is worth studying. OBJECTIVE:To investigate the biomechanical effects of proximal fibular fractures on various structures of the knee joint in an extended state. METHODS:Finite element method was used to conduct simulated biomechanical experiments.A healthy young male volunteer was selected to establish a finite element model of the knee joint in an extended state using MRI and CT image data,and four proximal fibular shapes were simulated(Model A:intact,Model B:1 cm fracture below the fibular head,Model C:1 cm tip defect fracture from the proximal end of the fibula to the distal end,and Model D:2 cm bone defect from the proximal end of the fibula).A longitudinal concentrated load of 1 500 N was applied to the femoral shaft to compare and analyze the distribution and changing trend of the maximum equivalent stress and maximum first principal stress of each structure of the knee joint in an extended state under four working conditions. RESULTS AND CONCLUSION:(1)In Model A,the maximum equivalent stress in the tibial cartilage and lateral compartment of the meniscus was greater than that in the medial compartment,while the maximum first principal stress in the tibial plateau and medial compartment of the meniscus was greater than that in the lateral compartment.The maximum equivalent stress of the medial condyle of the femoral cartilage was greater than that of the lateral condyle,and the maximum first principal stress of the medial condyle of the femoral cartilage was greater than that of the medial condyle.(2)Compared to Model A,there was no significant difference in the magnitude and distribution of the maximum equivalent stress and maximum first principal stress in the cartilage and meniscus of Model C.(3)Compared to Model A,the maximum equivalent stress increase amplitude of Model B was in the order of medial tibial cartilage(14.9％),medial condyle of femoral cartilage(13.6％),and medial meniscus(6.6％).The maximum first principal stress increase amplitude was the medial meniscus(11.06％),the medial tibial cartilage(8.65％),and the medial condyle of the femoral cartilage(7.46％).The maximum equivalent stress increase amplitude of the ligament was as follows:popliteal arch ligament(33.2％)>anterior cruciate ligament(21.3％)>fibular collateral ligament(17％)>posterior cruciate ligament(14.3％)>anterior lateral collateral ligament(13.2％)>medial collateral ligament(10.1％).(4)Compared to Model A,the maximum equivalent stress increasing trend of Model D followed the medial tibial cartilage(19.5％),femoral cartilage medial condyle(17.9％),and medial meniscus(9.9％).The maximum first principal stress in sequence was the medial meniscus(14.04％),the medial tibial cartilage(13.03％),and the medial condyle of the femoral cartilage(11.37％).The increasing trend of maximum equivalent stress in ligaments was as follows:anterior cruciate ligament(25.2％)>posterior cruciate ligament(18.9％)>medial collateral ligament(18.5％)>anterior lateral collateral ligament(12.7％).(5)It is suggested that when the knee joint is extended,a 1 cm fracture below the fibular head and a 2 cm fibular tip bone defect have a significant impact on the structure of the medial ventricular cartilage,anterior cruciate ligament,and posterior lateral ligament complex.

AIM: To explore the mechanism of Ginkgo biloba in the treatment of steroid-induced osteonecrosis of the femoral head based on network pharmacology. METHODS: The active ingredients and targets of Ginkgo biloba were predicted by the TCMSP, ADME, and PharmMapper databases. The disease targets related to steroid-induced osteonecrosis of the femoral head were searched by the GeneCards and OMIM databases. Cytoscape 3.6.1 was used to construct a protein-protein interaction network. The core target analysis, modular analysis, GO enrichment analysis, and KEGG pathway analysis of the targets of Ginkgo biloba in the intervention of steroid-induced osteonecrosis of the femoral head were performed by the STRING database. RESULTS: In this study, a total of 16 active ingredients of Ginkgo biloba and 547 targets were screened, of which 133 targets were related to steroid-induced femoral head necrosis. By PPI network topology analysis, TP53, AKT1, IL6, VEGFA, MAPK1, JUN, MAPK8, EGFR, EGF, and MYC were identified as the core targets. GO modularization analysis showed that these core targets were mainly related to apoptosis and angiogenesis. GO enrichment analysis was used to analyze the biological processes, cellular localization, and molecular functions of the core targets. KEGG enrichment analysis showed that the targets were mainly involved in molecular signaling pathways, among which the PI3K/AKT signaling pathway was the most relevant. CONCLUSION: Ginkgo biloba can inhibit steroid-induced osteonecrosis of the femoral head through multiple components, targets, and pathways, which provides the theoretical basis and reference for subsequent cell and animal experiments.

OBJECTIVE: To review the research progress in the construction strategy and application of bone/cartilage immunomodulating hydrogels. METHODS: The literature related to bone/cartilage immunomodulating hydrogels at home and abroad in recent years was reviewed and summarized from the immune response mechanism of different immune cells, the construction strategy of immunomodulating hydrogels, and their practical applications. RESULTS: According to the immune response mechanism of different immune cells, the biological materials with immunoregulatory effect is designed, which can regulate the immune response of the body and thus promote the regeneration of bone/cartilage tissue. Immunomodulating hydrogels have good biocompatibility, adjustability, and multifunctionality. By regulating the physical and chemical properties of hydrogel and loading factors or cells, the immune system of the body can be purposively regulated, thus forming an immune microenvironment conducive to osteochondral regeneration. CONCLUSION Immunomodulating hydrogels can promote osteochondral repair by affecting the immunomodulation process of host organs or cells. It has shown a wide application prospect in the repair of osteochondral defects. However, more data support from basic and clinical experiments is needed for this material to further advance its clinical translation process.
Hydrogels ; Cartilage ; Bone and Bones ; Tissue Engineering/methods*

Znic (Zn) alloys with good cytocompatibility and suitable degradation rate have been a kind of biodegradable metal with great potential for clinical applications. This paper summarizes the biological role of degradable Zn alloy as bone implant materials, discusses the mechanical properties of different Zn alloys and their advantages and disadvantages as bone implant materials, and analyzes the influence of different processing strategies (such as alloying and additive manufacturing) on the mechanical properties of Zn alloys. This paper provides systematic design approaches for biodegradable Zn alloys as bone implant materials in terms of the material selection, product processing, structural topology optimization, and assesses their application prospects with a view to better serve the clinic.
Orthopedics ; Zinc ; Alloys ; Dental Materials ; Prostheses and Implants

Objective:To investigate the effect of a degradable high-purity magnesium screw in fixing the greater trochanter bone flap of a lateral circumflex femoral artery transverse branch in the treatment of ischemic necrosis of femoral head in young and middle-aged adults.Methods:From February 2017 to February 2019, 12 cases (15 hips) of young and middle-aged patients with avascular necrosis of femoral head were treated in the Department of Orthopaedic of Affiliated Zhongshan Hospital of Dalian University. The age of patients was 30-53 years old. According to Association Research Circulation Osseous (ARCO), 2 hips were graded in stage II b, 4 in ARCO II c, 1 in ARCO III a, 5 in ARCO III b, 2 in ARCO III c and 1 in ARCO IV. The greater trochanter bone flap with a lateral circumferential vascular branch was used to fill the necrotic area, and fixed by a biodegradable high purity magnesium screw in the bone flap transfer. At 3, 6 and 12 months postoperation, the patient came to the hospital outpatient clinic for follow-up, and then were reviewed once a year. Imaging efficacy was evaluated by comparing preoperative and postoperative imaging. The Harris score and Visual Anoalogue Scale (VAS) score were tested at 12 and 24 months after surgery. The Harris score and VAS score before and after surgery were compared by Friedman test, and P<0.05 was considered statistically significant. Results:All 12 patients (15 hips) were entered in the 24-36 months of follow-up. At 12 and 24 months after surgery, Harris score was found at 87 (86, 92) and 90 (87, 92) respertively, which were both higher than that before surgery [59 (52, 74)] with a significant statistical difference ( Z=-3.743, Z=-4.473, P<0.05). However, there was no significant difference in Harris scores between 12 and 24 months after the surgery ( Z=-0.730, P>0.05). At the 12 and 24 months after surgery, VAS score was found at 3 (2, 3) and 2 (1, 3) respertively, which were both lower than that before surgery [6 (5, 6) ] with a significant statistical difference ( Z=-3.560, Z=-4.656, P<0.05). There was no statistical difference in VAS scores between 12 and 24 months after surgery ( Z=-1.095, P>0.05). X-ray and CT scan showed that the bone flaps healed well and the areas of osteonecrosis were repaired. Thirteen femoral heads were in good shape, and 2 femoral heads had further collapse of hips. No patients underwent joint replacement surgery at the time of last follow-up. Conclusion:Fixation of the greater trochanter flap of lateral circumflex femoral artery transverse branch with a degradable high-purity magnesium screw can ensure the healing of the flap at the implantation site and avoid the displacement and shedding of the flap. It is a new therapeutic option to treat the avascular necrosis of femoral head of young and middle-aged people.

Objective:To investigate the effect of flap combined with 3D printed microporous titanium(tantalum)prosthesis in the treatment of lower extremity soft tissue defect with large bone defect.Methods:From January 2019 to December 2020, 2 patients with large soft tissue defects on dorsal foot together with large metatarsal bone defect and 4 patients with soft tissue defects of calf with large tibial bone defect were treated. The areas of soft tissue defect were 5.0 cm×8.0 cm-15.0 cm×10.0 cm. The length of the bone defect were 3.8 cm to 7.0 cm, 5.75 cm in average. In the first stage, metatarsal bone defect or tibial bone defect was filled with vancomycin blended bone cement, meanwhile, soft tissue defect was repaired with anterolateral femoral flap(ALTF) with vascular anastomosis in 2 cases of feet, and local fascia flap was trans-positioned in 4 cases of lower extremity defects. The sizes of repairing flap were 6.0 cm×8.5 cm-16.0 cm×11.0 cm. Two to 7 months after the initial surgery, the customer designed microporous titanium prostheses were used(5 cases with microporous titanium and 1 with microporous tantalum) to repair the bone defects. The wound healing, the integration of metatarsal and tibial fractures with 3D printed microporous titanium(tantalum) prostheses, and the walking condition were observed after surgery. The follow-up lasted from 6 to 25 months, with an average of 12.7 months.Results:The wound healing in 5 patients was good. The patients stood on the foot in 2 months after surgery, started to walk with the assistance of crutch in 3 months after surgery, and took walk without assistance in 5-6 months after surgery. Good osseous integration were achieved. One diabetic patient had infection of foot wound 3 months after surgery. After removal of microporous titanium prosthesis and replacement of vancomycin blended interstitial substance of bone cement, the wound healed and the patient resumed walking.Conclusion:It is an effective method to encourage the patients to take early ambulation after the surgery for lower extremity soft tissue defect with large bone defect that was repaired by a flap and 3D printed microporous titanium(tantalum)prosthesis. Further observations are required to investigate the long-term efficacy, and the reduction of prosthesis infection rate requires further exploration.