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.

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.

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.

Objective To explore early postoperative gait characteristics and clinical outcomes after total knee arthroplasty(TKA).Methods From February 2023 to July 2023,26 patients with unilateral knee osteoarthritis(KOA)were treated with TKA,including 4 males and 22 females,aged from 57 to 85 years old with an average of(67.58±6.49)years old;body mass in-dex(BMI)ranged from 18.83 to 38.28 kg·m-2 with an average of(26.43±4.15)kg·m-2;14 patients on the left side,12 pa-tients on the right side;according to Kellgren-Lawrence(K-L)classification,6 patients with grade Ⅲ and 20 patients with grade Ⅳ;the courses of disease ranged from 1 to 14 years with an average of(5.54±3.29)years.Images and videos of standing up and walking,walking side shot,squatting and supine kneeling were taken with smart phones before operation and 6 weeks after operation.The human posture estimation framework OpenPose were used to analyze stride frequency,step length,step length,step speed,active knee knee bending angle,stride length,double support phase time,as well as maximum hip flexion angle and maximum knee bending angle on squatting position.Western Ontario and McMaster Universities(WOMAC)arthritis index and Knee Society Score(KSS)were used to evaluate clinical efficacy of knee joint.Results All patients were followed up for 5 to 7 weeks with an average of(6.00±0.57)weeks.The total score of WOMAC decreased from(64.85±11.54)before op-eration to(45.81±7.91)at 6 weeks after operation(P＜0.001).The total KSS was increased from(101.19±9.58)before opera-tion to(125.50±10.32)at 6 weeks after operation(P＜0.001).The gait speed,stride frequency and stride length of the affected side before operation were(0.32±0.10)m·s-1,(96.35±24.18)steps·min-1,(0.72±0.14)m,respectively;and increased to(0.48±0.11)m·s 1,(104.20±22.53)steps·min-1,(0.79±0.10)m at 6 weeks after operation(P＜0.05).The lower limb support time and active knee bending angle decreased from(0.31±0.38)sand(125.21±11.64)° before operation to(0.11±0.04)s and(120.01±13.35)° at 6 weeks after operation(P＜0.05).Eleven patients could able to complete squat before operation,13 patients could able to complete at 6 weeks after operation,and 9 patients could able to complete both before operation and 6 weeks after operation.In 9 patients,the maximum bending angle of crouching position was increased from 76.29° to 124.11° before operation to 91.35° to 134.12° at 6 weeks after operation,and the maximum bending angle of hip was increased from 103.70° to 147.25° before operation to 118.61° to 149.48° at 6 weeks after operation.Conclusion Gait analysis technology based on artificial intelligence image recognition is a safe and effective method to quantitatively identify the changes of pa-tients'gait.Knee pain of KOA was relieved and the function was improved,the supporting ability of the affected limb was im-proved after TKA,and the patient's stride frequency,stride length and stride speed were improved,and the overall movement rhythm of both lower limbs are more coordinated.

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.