Robotic joint surgery (RJS) has demonstrated high precision and reproducibility in total hip and knee arthroplasty,the integration of artificial intelligence(AI) has further enhanced the intelligence level of key processes,including surgical planning,registration,surgical manipulator control,and robot autonomy. AI-powered surgical planning improves implant positioning accuracy through deep learning,while AI-powered registration overcomes the limitations of traditional methods in precision and efficiency. Additionally,reinforcement learning and neural networks have optimized surgical manipulator control,improving operational accuracy and human-robot interaction. As AI continues to advance,RJS is expected to make significant strides in automation,multimodal sensing,and human-robot collaboration,driving arthroplasty surgeries toward higher levels of intelligence and individual treatment.

Robotic joint surgery (RJS) has demonstrated high precision and reproducibility in total hip and knee arthroplasty,the integration of artificial intelligence(AI) has further enhanced the intelligence level of key processes,including surgical planning,registration,surgical manipulator control,and robot autonomy. AI-powered surgical planning improves implant positioning accuracy through deep learning,while AI-powered registration overcomes the limitations of traditional methods in precision and efficiency. Additionally,reinforcement learning and neural networks have optimized surgical manipulator control,improving operational accuracy and human-robot interaction. As AI continues to advance,RJS is expected to make significant strides in automation,multimodal sensing,and human-robot collaboration,driving arthroplasty surgeries toward higher levels of intelligence and individual treatment.

BACKGROUND:The number of hip fracture patients with dementia is increasing with an aging population,posing challenges for surgical treatment. OBJECTIVE:To determine the effect of dementia on postoperative complications in older patients with hip fractures. METHODS:Patients aged over 60 years old with hip fractures from 2000 to 2019 at Chinese PLA General Hospital were included.Dementia patients with a preexisting diagnosis of dementia at admission were identified.Each dementia patient was matched,for age±5 years,gender,and fracture type with 10 non-dementia patients.The differences in postoperative complications were compared between the two groups,including pneumonia,respiratory failure,gastrointestinal bleeding,urinary tract infection,surgical site infection,deep venous thrombosis,pulmonary embolism,angina pectoris,arrhythmia,heart failure,myocardial infarction,stroke,and death.The impact of dementia on major complications was evaluated using multivariate conditional logistic regression. RESULTS AND CONCLUSION:A total of 2 887 patients were included,of whom 125(4.3%)were dementia patients and matched with 1 243 non-dementia patients.The average age of dementia patients was(80.6±7.4)years;64.8%were female;53.6%were intertrochanteric fractures,and 46.4%were femoral neck fractures.Major complications occurred in 25(20.0%)patients with dementia and 123(9.9%)patients without dementia(P<0.01).The risk of major complications was 200.0 per 1 000 persons(95%CI,139.3-278.6)in dementia patients and 99.0 per 1 000 persons(95%CI,83.6-116.9)in non-dementia patients.Multivariate conditional logistic regression showed that a 2-fold risk of major postoperative complications after hip fracture surgery was found in dementia patients than in those without dementia(adjusted OR,2.11;95%CI,1.08-4.10).The results show that dementia is an independent risk factor for postoperative complications in elderly patients with hip fractures.Appropriate preoperative risk assessment and corresponding preventive and therapeutic measures should be given to this vulnerable population to mitigate postoperative complications.

BACKGROUND:As tissue engineering brings new hope to the worldwide problem of articular cartilage repair,the construction of light-curing 3D printed hydrogel scaffolds with biomimetic composition is of great significance for cartilage tissue engineering. OBJECTIVE:To construct a biomimetic methacryloylated hyaluronic acid/acellular Wharton's jelly composite hydrogel scaffold by digital light processing 3D printing technology,and to evaluate its biocompatibility. METHODS:Wharton's jelly was isolated and extracted from human umbilical cord,then decellulated,freeze-dried,ground into powder,and dissolved in PBS to prepare 50 g/L acellular Wharton's jelly solution.Methylallylated hyaluronic acid was prepared,lyophilized and dissolved in PBS to prepare 50 g/L methylallylated hyaluronic acid solution.Acellular Wharton's jelly solution was mixed with methacrylyacylated hyaluronic acid solution at a volume ratio of 1:1,and was used as bio-ink after adding photoinitiator.Methylacrylylated hyaluronic acid hydrogel scaffolds(labeled as HAMA hydrogel scaffolds)and methylacrylylated hyaluronic acid/acellular Wharton's jelly gel scaffolds(labeled as HAMA/WJ hydrogel scaffolds)were prepared by digital light processing 3D printing technology,and the microstructure,swelling performance,biocompatibility,and cartilage differentiation performance of the scaffolds were characterized. RESULTS AND CONCLUSION:(1)Under scanning electron microscope,the two groups of scaffolds showed a three-dimensional network structure,and the fiber connection of HAMA/WJ hydrogel scaffold was more uniform.Both groups achieved swelling equilibrium within 10 hours,and the equilibrium swelling ratio of HAMA/WJ hydrogel scaffold was lower than that of HAMA hydrogel scaffold(P＜0.05).(2)CCK-8 assay showed that HAMA/WJ hydrogel scaffold could promote the proliferation of bone marrow mesenchymal stem cells compared with HAMA hydrogel scaffold.Dead/live staining showed that bone marrow mesenchymal stem cells grew well on the two groups of scaffolds,and the cells on the HAMA/WJ hydrogel scaffolds were evenly distributed and more cells were found.Phalloidine staining showed better adhesion and spread of bone marrow mesenchymal stem cells in HAMA/WJ hydrogel scaffold than in HAMA.(3)Bone marrow mesenchymal stem cells were inoculated into the two groups for chondrogenic induction culture.The results of qRT-PCR showed that the mRNA expressions of agglutinoglycan,SOX9 and type Ⅱ collagen in the HAMA/WJ hydrogel scaffold group were higher than those in the HAMA hydrogel scaffold group(P＜0.05,P＜0.01).(4)These findings indicate that the digital light processing 3D bioprinting HAMA/WJ hydrogel scaffold can promote the proliferation,adhesion,and chondrogenic differentiation of bone marrow mesenchymal stem cells.

BACKGROUND:Compared with traditional two-dimensional culture,three-dimensional microtissue culture can show greater advantages.However,more favorable cultivation methods in three-dimensional culture still need to be further explored. OBJECTIVE:To evaluate the cell behavior of microtissue and its ability to promote cartilage formation under two three-dimensional culture methods. METHODS:Cartilage-derived microcarriers were prepared by chemical decellularization and tissue crushing.DNA quantification and nuclear staining were used to verify the success of decellularization,and histological staining was used to observe the matrix retention before and after decellularization.The microcarriers were characterized by scanning electron microscopy and CCK-8 assay.Cartilage-derived microtissues were constructed by combining cartilage-derived microcarriers with human adipose mesenchymal stem cells through three-dimensional static culture and three-dimensional dynamic culture methods.The cell viability and chondrogenic ability of the two groups of microtissues were detected by scanning electron microscopy,live and dead staining,and RT-qPCR. RESULTS AND CONCLUSION:(1)Cartilage-derived microcarriers were successfully prepared.Compared with before decellularization,the DNA content significantly decreased after decellularization(P<0.001).Scanning electron microscope observation showed that the surface of the microcarrier was surrounded by collagen,maintaining the characteristics of the natural extracellular matrix of cartilage cells.CCK-8 assay indicated that microcarriers had no cytotoxicity and could promote cell proliferation.(2)Scanning electron microscopy and live and dead staining results showed that compared with the three-dimensional static group,the three-dimensional dynamic group had a more extended morphology of microtissue cells,and extensive connections between cells and cells,between cells and matrix,and between matrix.(3)The results of RT-qPCR showed that the expressions of SOX9,proteoglycan,and type Ⅱ collagen in microtissues of both groups were increased at 7 or 14 days.The relative expression levels of each gene in the three-dimensional dynamic group were significantly higher than those in the three-dimensional static group at 14 days(P<0.05).At 21 days,the three-dimensional static group had significantly higher gene expression compared with the three-diomensional dynamic group(P<0.001).(4)The results showed that compared with three-dimensional static culture microtissue,three-dimensional dynamic culture microtissue could achieve higher expression of chondrogen-related genes in a shorter time,showing better cell viability and chondrogenic ability.

BACKGROUND:Tissue engineering has brought new hope to the clinical challenge of liver failure,and the preparation of plant-derived decellularized fiber scaffolds holds significant importance in liver tissue engineering. OBJECTIVE:To prepare apple tissue decellularized scaffold material by using fresh apple slices and a solution of sodium dodecyl sulfate,and assess its biocompatibility. METHODS:Fresh apples were subjected to decellularization using phosphate buffer saline and sodium dodecyl sulfate solution,separately.Afterwards,the decellularized apple tissues and apple decellularized scaffold materials were decontaminated with phosphate buffer saline.Subsequently,scanning electron microscopy was used to assess the effectiveness of decellularization of the apple materials.Adipose-derived mesenchymal stem cells were extracted from the inguinal fat BALB/C of mice,and their expression of stem cell-related markers(CD45,CD34,CD73,CD90,and CD105)was identified through flow cytometry.The cells were then divided into a scaffold-free control group and a scaffold group.Equal amounts of adipose-derived mesenchymal stem cells were seeded onto both groups.The biocompatibility of the decellularized scaffold with adipose-derived mesenchymal stem cells was evaluated using CCK-8 assay,hematoxylin-eosin staining,and phalloidine staining.Cell adhesion and growth on the scaffold were observed under light microscopy and scanning electron microscopy.Furthermore,the scaffold was subdivided into the non-induced group and the hepatogenic-induced group.Adipose-derived mesenchymal stem cells were cultured on the decellularized apple scaffold,and they were cultured for 14 days in regular culture medium or hepatogenic induction medium for comparison.Immunofluorescent staining using liver cell markers,including albumin,cytokeratin 18,and CYP1A1,was performed.Enzyme-linked immunosorbent assay was used to detect the secretion of alpha fetoprotein and albumin.Additionally,scanning electron microscopy was employed to observe the morphology of the induced cells on the scaffold,verifying the expression of liver cell-related genes on the decellularized scaffold material.Finally,the cobalt-60 irradiated and sterilized decellularized apple scaffolds were transplanted onto the surface of mouse liver and the degradation of the scaffold was observed by gross observation and hematoxylin-eosin staining after 28 days. RESULTS AND CONCLUSION:(1)The scanning electron microscopy results revealed that the decellularized apple scaffold material retained a porous structure of approximately 100 μm in size,with no residual cells observed.(2)Through flow cytometry analysis,the cultured cells were identified as adipose-derived mesenchymal stem cells.(3)CCK-8 assay results demonstrated that the prepared decellularized apple tissue scaffold material exhibited no cytotoxicity.Hematoxylin-eosin staining and phalloidine staining showed that adipose-derived mesenchymal stem cells were capable of adhering and proliferating on the decellularized apple tissue scaffold.(4)The results obtained from immunofluorescence staining and enzyme-linked immunosorbent assay revealed that adipose-derived mesenchymal stem cells cultured on the decellularized apple scaffolds exhibited elevated expression of liver-specific proteins,including albumin,alpha-fetoprotein,cytokeratin 18,and CYP1A1.These results suggested that they were induced differentiation into hepatocyte-like cells possessing functional characteristics of liver cells.(5)The decellularized apple scaffold implanted at 7 days has integrated with the liver,with partial degradation of the scaffold observed.By 28 days,the decellularized apple scaffold has completely degraded and has been replaced by newly-formed tissue.(6)The results indicate that the decellularized scaffold material derived from apple tissue demonstrates favorable biocompatibility,promoting the proliferation,adhesion,and hepatic differentiation of adipose-derived mesenchymal stem cells.

Limb dismemberment injuries are common in clinical practice,and safe and effective protection of the dismembered limb is the key to successful limb replantation.Normothermic machine perfusion has made significant breakthrough in the field of organ transplantation,which may maintain the active function of organs and tissues for a long period of time and prolong the preservation time.These findings have been validated in large animal models and clinical trials.Meantime,this technology is expected to provide novel reference for the preservation and functional recovery of severed limbs.Therefore,this paper reviews the problems of static cold preservation in the preservation of disarticulated limbs,the development history of mechanical perfusion,the current status of clinical application of ambient mechanical perfusion of disarticulated limbs as well as the problems to be solved,and looks forward to the direction of its development and the prospect of its clinical application,with a view to promoting the wide application of this technology in the clinic.

Although blood banks based on human blood can provide blood transfusions for the wounded timely and effec-tively,scientific research has never given up on finding new blood sources due to the restrictions of human blood sources.With the application of transgenic technology and the successful breeding of gene-edited pigs,gene-edited pig blood as a po-tential source of clinical transfusion has attracted wide attention.Now there are preclinical studies showing the feasibility of transfusing gene-edited pig red blood cells into primates.This paper discusses the related research and future development of xenogeneic transfusion of porcine red blood cells by gene editing.

The technology in spinal surgery clinical treatment is undergoing revolutionary changes in recent years. Artificial intelligence shows promise in enhancing diagnosis, personalizing treatment, and predicting outcomes. Robotic surgery improves safety and precision but its cost-effectiveness limits widespread use. Augmented reality can enhance screw placement accuracy and efficiency, yet requires refinement in precision and user interaction. Three-dimensional printing, through personalized guides and implants, optimizes surgical procedures, though further clinical studies are needed to validate long-term benefits. New implant designs and materials, facilitated by topological optimization, carbon fiber composite polyetheretherketone, present opportunities for creating anatomically and biomechanically congruent spinal implants. This review analyzes the potential and challenges of these advancements in improving surgical accuracy, reducing complications, and meeting individualized treatment needs, aiming to foster the development of more effective and safer spinal surgical techniques. These technologies collectively offer enhanced precision and patient outcomes, signifying a transformative shift in spinal healthcare.

Objective To compare the biomechanical properties of new type of unicortical and unilateral external fixators by finite element analysis.Methods Firstly,a tibia model was reconstructed based on the CT data images using Mimics software,and then processed and modified by Geomagic Wrap software.Secondly,Solidworks software was used to establish the 3D models for new type of unicortical and unilateral external fixators,and fracture defect was made in the tibia model and then the model was assembled with the external fixators.Finally,mesh delineation was performed using ABAQUS software,and axial compression,torsion and bending loads were applied to the assemblies,respectively,to observe the stress distributions and fracture displacements and to evaluate the biomechanical properties of the 2 types of external fixators.Results The new type of unicortical external fixator had the mean and maximum stresses at the nail-bone interface and the stress distribution at the pin-bone contact surface lower than those of the unilateral external fixator under the three different loads,which behaved better in torsional resistance while worse in axial compression and bending resistance than the unilateral external fixator.Conclusion The new type of unicortical external fixator has the biomechanical stability slightly weaker than that of the unilateral external fixator,which shows sufficient stability and reasonable load distribution when used for temporary fixation with lower likelihood of nail breaking,periprosthetic fractures of the tibia pin tract and loosening of the bone pins when compared with the unilateral external fixator.[Chinese Medical Equipment Journal,2024,45(11):32-38]