OBJECTIVE To investigate the mechanism of Xibining Ⅱ formula in alleviating synovial inflammation and fibrosis in knee osteoarthritis （KOA） rats based on Janus kinase 2 （JAK2）/signal transducer and activator of transcription 3 （STAT3） pathway. METHODS Seventy-five male SD rats were randomly divided into sham operation group （Sham group）， KOA group， Xibining Ⅱ low-dose group （XBNⅡ-L group， 4 g/kg）， Xibining Ⅱ high-dose group （XBNⅡ-H group， 8 g/kg）， and Xibining Ⅱ high-dose combined with STAT3 activator Colivelin trifluoroacetate （C-TFA） group [C-TFA group， 8 g/kg Xibining Ⅱ+ 1.0 mg/（kg·d） C-TFA]， with 15 rats in each group. Except for the Sham group， the KOA model was established by anterior cruciate ligament transection in the other groups. After successful modeling， each group was given corresponding drugs by intragastric administration and （or） intraperitoneal injection once daily for 28 consecutive days. After the last medication， the pathological changes of synovial tissue of knee joint in each group were evaluated and the indicators were calculated. The levels of serum inflammatory factors were detected. The positive expressions of phosphorylated JAK2 （p-JAK2） and phosphorylated STAT3 （p-STAT3） in synovial tissue of the knee joint were detected. The expressions of JAK2/STAT3 pathway-related proteins and mRNAs in synovial tissue were detected. RESULTS Compared with the Sham group， the synovial lining cells in the KOA group showed significant proliferation and disordered arrangement； the Krenn score， fibrosis ratio， positive area percentage of p-JAK2 and p-STAT3， p-JAK2/JAK2 and p-STAT3/STAT3， protein expression of Collagen-Ⅰ and α -smooth muscle actin， the mRNA expression of JAK2， STAT3， Collagen-Ⅰ and α -smooth muscle actin， as well as serum levels of interleukin-1β and interleukin-18 were significantly increased （ P ＜0.05）. Compared with the KOA group， the above pathological changes were significantly improved in each dose group of Xibining Ⅱ formula， and all indicators were significantly decreased （ P ＜0.05）， with the XBNⅡ-H group showing better effects than the XBNⅡ-L group （ P ＜0.05）. Compared with the XBNⅡ-H group， the above pathological damages were aggravated in the C-TFA group， and all indicators were significantly worsened （ P ＜0.05）. CONCLUSIONS Xibining Ⅱ formula can alleviate synovial inflammation and fibrosis in KOA rats， and its mechanism may be related to inhibiting the activation of JAK2/STAT3 pathway.

Objective:To investigate the change trend in the burden of 5 common malignant tumors of digestive system (esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer and liver cancer) in the Chinese population from 1990 to 2021.Methods:The descriptive epidemio-logic method was conducted. The number of new cases, crude incidence rate, age-standardized incidence rate, the number of deaths, crude mortality rate and age-standardized mortality rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021 of the Global Burden of Disease were collected. The age-standardized rate was calculated based on the standardized demographics of the whole world in the Global Burden of Disease for the year 2021. Observation indicators: (1) The incidence of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021; (2) the mortality of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021; (3) the change trend of age-standardized incidence rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021; (4) the change trend of age-standardized mortality rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The Joinpoint regression model was constructed for trend analysis, specifically to calculate the annual percentage change, average annual percentage change (AAPC), and their 95% confidence interval ( CI) for age-standardized incidence and mortality rates for each cancer type at different time periods. Results:(1) The incidence of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The number of new cases of esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer and liver cancer in the Chinese population changed from 207 495, 407 471, 158 389, 37 818 and 96 434 in 1990 to 320 805, 611 799, 658 321, 118 665 and 196 637 in 2021. The crude incidence rates of the above cancer types changed from 17.64/100 000, 34.64/100 000, 13.46/100 000, 3.21/100 000, 8.20/100 000 in 1990 to 22.55/100 000, 43.00/100 000, 46.27/100 000, 8.34/100 000, 13.82/100 000 in 2021. The new cases of esophageal cancer, stomach cancer, colorectal cancer, pancreatic cancer, and liver cancer all showed an increasing trend, with absolute changes of 54.61%, 50.15%, 315.64%, 213.78%, and 103.91%, respectively. (2) The mortality of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The number of deaths of esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer and liver cancer in the Chinese population changed from 210 821, 374 066, 119 303, 38 883 and 94 937 in 1990 to 296 443, 445 013, 275 129, 119 602 and 172 068 in 2021. The crude death rates of the above cancer types changed from 17.92/100 000, 31.80/100 000, 10.14/100 000, 3.31/100 000, 8.07/100 000 in 1990 to 20.84/100 000, 31.28/100 000, 19.34/100 000, 8.41/100 000, 12.09/100 000 in 2021. Death cases of esophageal cancer, stomach cancer, colorectal cancer, pancreatic cancer, and liver cancer all showed an increa-sing trend, with absolute changes of 40.61%, 18.97%, 130.61%,207.59%, and 81.24%, respectively. (3) The change trend of age-standardized incidence rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The change trends of age-standardized incidence rates of esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer, and liver cancer in the Chinese population were divided into 5, 5, 4, 5, and 5 periods, respectively, and the AAPCs of age-standardized incidence rates of the above cancer types were -1.60% (95% CI as -1.78% to -1.42%), -1.60% (95% CI as -1.78% to -1.43%), 1.66% (95% CI as 1.39% to 1.94%), 0.72% (95% CI as 0.36% to 1.08%), and -0.31% (95% CI as -0.39% to -0.23%). (4) The change trend of age-standardized mortality rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The change trend of age-standardized mortality rates of esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer, and liver cancer in the Chinese population were divided into 5, 5, 4, 5, and 4 periods, respectively, and the AAPC of age-standardized mortality rates for each of the above mentioned cancer types were -1.96% (95% CI as -2.03% to -1.90%), -2.44% (95% CI as -2.50% to -2.38%), -0.49% (95% CI as -0.58% to -0.41%), 0.56% (95% CI as 0.48% to 0.63%), and -0.68% (95% CI as -0.89% to -0.52%). Conclusions:From 1990 to 2021, the disease burden of esophageal cancer, gastric cancer and liver cancer in the Chinese population show a downward trend. The standardized incidence of colorectal cancer shows an upward trend, and the standardized mortality rate shows a downward trend. The disease burden of pancreatic cancer shows an upward trend.

Background and purpose:Prostate cancer and breast cancer are highly prevalent malignant tumors,and there occurrence and development are related to the tumor suppressor genes phosphatase and tensin homolog deleted on chremosome ten(Pten)and the transformation related protein 53 gene(Trp53).The loss of function of Trp53 is closely related.The simultaneous loss of the two can accelerate the malignant progression of tumors and induce therapeutic resistance.The gene-edited spontaneous tumor model of mice based on the Cre-loxP system is a key tool for studying the mechanism of cancer.Studies have shown that prostate-specific promoter(probasin,Pbsn)-driven iCre recombinase(Pbsn-iCre)can induce spontaneous prostate cancer in male mice,but its role in female breast cancer and transgender expression characteristics have not yet been clarified.In this study,we constructed Ptenfl/fl;Trp53fl/fl;Pbsn-iCre+transgenic mouse model which was designed to explore its spontaneous tumor phenotype in prostate cancer and breast cancer,and to verify the expression characteristics of Pbsn in breast tissue.Methods:The Ptenfl/fl;Trp53fl/fl;Pbsn-iCre+mouse model was established using Cre-loxP system by hybridization and continuous backcross screening with Ptenfl/fl mouse,Trp53fl/flmouse,and Pbsn-iCre+mouse(Ethical No.:FUSCC-IACUC-2025115).Pten,Trp53 and Pbsn-iCre genotypes were verified by polymerase chain reaction and agarose gel electrophoresis.The incidence of tumor in transgenic mice was monitored,and the histopathological characteristics of tumor were evaluated by hematoxylin-eosin staining.The protein levels of Pten and p53 in prostate and breast tumor tissues were analyzed by immunohistochemistry,and the distributions of Pbsn in breast,prostate,ovary,heart,liver and kidney were detected.Results:Ptenfl/fl;Trp53fl/fl;Pbsn-iCre+male mouse developed spontaneous prostate tumor at age of 5 month,and female mouse developed spontaneous breast tumor at age of 6 months.The pathological manifestations of prostate cancer were invasive acinar adenocarcinoma structure with glandular structure disorder and basement membrane destruction.The pathological manifestations of breast cancer were invasive ductal carcinoma with ductal epithelial dysplasia and interstitial lymphocyte infiltration.Immunohistochemistry confirmed the complete deletion of Pten and p53 proteins in prostate and breast tumor tissues,which verified the prostate and mammary gland specific gene knockout effect.Immunohistochemistry also confirmed that Pbsn protein was specifically expressed in prostate acinar epithelial cells,ovarian tissue,and mammary duct epithelial cells,but not in heart,liver and kidney.Conclusion:Pbsn-iCre is functionally expressed in female mammary glands,and the simultaneous loss of Pten/Trp53 induced by Pbsn-iCre may drive the development of prostate cancer in male and breast cancer in female mouse.

Objective:To investigate the change trend in the burden of 5 common malignant tumors of digestive system (esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer and liver cancer) in the Chinese population from 1990 to 2021.Methods:The descriptive epidemio-logic method was conducted. The number of new cases, crude incidence rate, age-standardized incidence rate, the number of deaths, crude mortality rate and age-standardized mortality rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021 of the Global Burden of Disease were collected. The age-standardized rate was calculated based on the standardized demographics of the whole world in the Global Burden of Disease for the year 2021. Observation indicators: (1) The incidence of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021; (2) the mortality of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021; (3) the change trend of age-standardized incidence rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021; (4) the change trend of age-standardized mortality rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The Joinpoint regression model was constructed for trend analysis, specifically to calculate the annual percentage change, average annual percentage change (AAPC), and their 95% confidence interval ( CI) for age-standardized incidence and mortality rates for each cancer type at different time periods. Results:(1) The incidence of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The number of new cases of esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer and liver cancer in the Chinese population changed from 207 495, 407 471, 158 389, 37 818 and 96 434 in 1990 to 320 805, 611 799, 658 321, 118 665 and 196 637 in 2021. The crude incidence rates of the above cancer types changed from 17.64/100 000, 34.64/100 000, 13.46/100 000, 3.21/100 000, 8.20/100 000 in 1990 to 22.55/100 000, 43.00/100 000, 46.27/100 000, 8.34/100 000, 13.82/100 000 in 2021. The new cases of esophageal cancer, stomach cancer, colorectal cancer, pancreatic cancer, and liver cancer all showed an increasing trend, with absolute changes of 54.61%, 50.15%, 315.64%, 213.78%, and 103.91%, respectively. (2) The mortality of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The number of deaths of esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer and liver cancer in the Chinese population changed from 210 821, 374 066, 119 303, 38 883 and 94 937 in 1990 to 296 443, 445 013, 275 129, 119 602 and 172 068 in 2021. The crude death rates of the above cancer types changed from 17.92/100 000, 31.80/100 000, 10.14/100 000, 3.31/100 000, 8.07/100 000 in 1990 to 20.84/100 000, 31.28/100 000, 19.34/100 000, 8.41/100 000, 12.09/100 000 in 2021. Death cases of esophageal cancer, stomach cancer, colorectal cancer, pancreatic cancer, and liver cancer all showed an increa-sing trend, with absolute changes of 40.61%, 18.97%, 130.61%,207.59%, and 81.24%, respectively. (3) The change trend of age-standardized incidence rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The change trends of age-standardized incidence rates of esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer, and liver cancer in the Chinese population were divided into 5, 5, 4, 5, and 5 periods, respectively, and the AAPCs of age-standardized incidence rates of the above cancer types were -1.60% (95% CI as -1.78% to -1.42%), -1.60% (95% CI as -1.78% to -1.43%), 1.66% (95% CI as 1.39% to 1.94%), 0.72% (95% CI as 0.36% to 1.08%), and -0.31% (95% CI as -0.39% to -0.23%). (4) The change trend of age-standardized mortality rate of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021. The change trend of age-standardized mortality rates of esophageal cancer, gastric cancer, colorectal cancer, pancreatic cancer, and liver cancer in the Chinese population were divided into 5, 5, 4, 5, and 4 periods, respectively, and the AAPC of age-standardized mortality rates for each of the above mentioned cancer types were -1.96% (95% CI as -2.03% to -1.90%), -2.44% (95% CI as -2.50% to -2.38%), -0.49% (95% CI as -0.58% to -0.41%), 0.56% (95% CI as 0.48% to 0.63%), and -0.68% (95% CI as -0.89% to -0.52%). Conclusions:From 1990 to 2021, the disease burden of esophageal cancer, gastric cancer and liver cancer in the Chinese population show a downward trend. The standardized incidence of colorectal cancer shows an upward trend, and the standardized mortality rate shows a downward trend. The disease burden of pancreatic cancer shows an upward trend.

Objective To investigate the effects of inclined axial compressive force and flexion moment on the anterior and posterior shear stiffness of the lumbosacral segment.Methods Six fresh-frozen human cadaveric L5-S1 segments were tested under intact and two progressively impaired structural conditions:intact,a 4-mm bilateral facet joint gap,and anterior discectomy with nucleus pulposus removal plus circumferential release of the inner annular fibers(disc injury).A 300 N axial compressive force was applied either vertically downward or with a 10° or 20° anterior inclination through the disc's shear center.Anterior(0 N to 250 N)and posterior(-50 N to 0 N)shear tests were conducted using a material testing machine.These tests were repeated under a 5 N-m flexion moment.The relative motion between L5 and Si was measured using a three-dimensional motion capture system.Results In the intact state,the inclination of the axial compressive force did not significantly alter anterior or posterior shear stiffness.However,the application of a flexion moment increased anterior shear stiffness by 49.3％.Progressive structural damage resulted in incremental increases in anteroposterior shear translation and corresponding reductions in stiffness.Notably,under combined loading with axial compression and flexion moment,anterior stiffness decreased from 939 N/mm(intact)to 224 N/mm(disc injury),while posterior stiffness decreased from 572 N/mm to 217 N/mm.Within the low-load range,no significant differences in shear stiffness were observed across any structural conditions,regardless of axial force inclination or combined with a flexion moment.Conclusions This study supports the clinical view that retro-inclination of the pelvis serves as a compensatory mechanism to enhance segmental shear stability.However,this compensatory capacity gradually diminishes and ultimately fails as spinal degeneration progresses.

AIM:To elucidate the mechanism by which Polygonatum sibiricum polysaccharides(PSP)miti-gate high-sugar diet-induced neuroinflammation through the gut microbiota-serum metabolome axis.METHODS:Fifty male ICR mice were divided into 5 groups:control group,model group,low-dose(250 mg/kg)PSP group,high-dose(500 mg/kg)PSP group,and donepezil hydrochloride(3 mg/kg)group.The neuroinflammation model was established through administration of high-sugar chow and 10%sucrose water for 12 weeks.Cognitive function assessment was per-formed utilizing the Morris water maze.Hippocampal histopathology was examined by hematoxylin-eosin(HE)staining,activated microglia were assessed via immunofluorescence,and neuronal apoptosis was evaluated by TUNEL assay.Serum and hippocampal levels of interleukin-6(IL-6),IL-1β,tumor necrosis factor-α(TNF-α)and nitric oxide(NO)were quantified using ELISA and Western blot.Gut microbiota diversity and serum untargeted metabolomics analyses were car-ried out employing 16S rRNA sequencing and LC-MS/GC-MS,respectively.Differential metabolites were screened,and key metabolic pathways were enriched using MetaboAnalyst 6.0.Spearman correlation analysis established relationships between gut microbiota,metabolites,and inflammatory factors.RESULTS:Model mice demonstrated increased escape latency(P<0.05 or P<0.01)and decreased platform crossings(P<0.01)compared with controls,which were reversed by PSP treatment(P<0.05 or P<0.01).Treatment with PSP substantially reduced IL-6,IL-1β,TNF-α and NO levels in se-rum and hippocampus(P<0.05 or P<0.01),diminished inflammatory infiltration,inhibited microglial activation,and re-duced neuronal damage.Gut microbiota analysis demonstrated that PSP increased Lactobacillus and Bacteroides abun-dance while reducing Alistipes(P<0.05).Metabolomics identified 15 differential metabolites(including betaine,kyotor-phin and ε-caprolactam)and highlighted the significance of alanine,aspartate and glutamate metabolism pathways.Spear-man analysis revealed that abundance of Alistipes and Bacteroides were positively correlated with IL-1β(P<0.05),while abundance of Lactobacillus was negatively correlated with inflammatory factors(P<0.05 or P<0.01).Key metabolites(be-taine,kyotorphin,ε-caprolactam,trans-cinnamate,cis-zeatin and galactitol)showed strong associations with inflamma-tion factors(P<0.05 or P<0.01).CONCLUSION:Treatment with PSP attenuates neuroinflammation through modula-tion of gut microbiota(Lactobacillus,Bacteroides and Alistipes),regulation of metabolites(betaine,kyotorphin and so on),and targeting amino acid metabolism pathways.

Objective:To evaluate the stability of percutaneous screw fixation for minimally invasive treatment of intra-articular calcaneal fractures using three-dimensional finite element analysis.Methods:CT scan was performed on the calcaneus of a normal adult for three-dimensional reconstruction. The DICOM data were imported into Mimics software to establish a model of a Sanders type IIB intra-articular calcaneal fracture. Based on the Essex-Lopresti classification of posterior facet morphology, the model was subdivided into two subtypes: tongue-type and depression-type. The calcaneus was divided into four fragments: sustentaculum tali, posterior tuberosity, anterior process (three points), and posterior articular surface (one surface). Two types of fixation methods, classical lateral anatomical plates and combinations of percutaneous screws, were simulated and performed. A three-dimensional finite element analysis was conducted by applying a stress combination of 420 N on the posterior subtalar articular surface, 200 N on the middle subtalar articular surface, and 300 N at the Achilles tendon insertion point. The maximum displacement and von Mises stress values of each bone fragment and implant were recorded to evaluate the biomechanical stability. For clinical validation, 34 patients with Sanders type IIB calcaneal fractures from Orthopedics Department of the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University were treated with percutaneous reduction and screw fixation using the following configurations.Results:Under simulated stress, the A4 group with medial support screws in the tongue-type fracture subgroup demonstrated minimal overall calcaneal displacement (0.22 mm) and internal fixation displacement (0.14 mm). For the depression-type, the B2 group with medial support screws showed lower maximum stress in the calcaneus and internal fixation, at 22.04 MPa and 41.14 MPa, respectively, along with the lowest overall displacement (0.14 mm). The peak stress of all groups of implants remained below the material yield strength. The A4 and B2 protocols were applied to 15 cases of tongue-type calcaneal fractures and 19 cases of collapse-type calcaneal fractures. At the final follow-up The American Orthopaedic Foot & Ankle Society ankle-hindfoot score scale was 86.1±5.82 and 87.2±5.18, respectively, while the visual analog scale for pain was 1.60±1.24 and 1.58±1.02, respectively.Conclusions:Percutaneous screw fixation provided reliable stability for Sanders type IIB calcaneal fractures. The fixation configuration incorporating a medial support screw offers superior biomechanical performance in both tongue-type and depression-type fractures, representing an optimized minimally invasive technique with strong clinical applicability.

AIM:To elucidate the mechanism by which Polygonatum sibiricum polysaccharides(PSP)miti-gate high-sugar diet-induced neuroinflammation through the gut microbiota-serum metabolome axis.METHODS:Fifty male ICR mice were divided into 5 groups:control group,model group,low-dose(250 mg/kg)PSP group,high-dose(500 mg/kg)PSP group,and donepezil hydrochloride(3 mg/kg)group.The neuroinflammation model was established through administration of high-sugar chow and 10%sucrose water for 12 weeks.Cognitive function assessment was per-formed utilizing the Morris water maze.Hippocampal histopathology was examined by hematoxylin-eosin(HE)staining,activated microglia were assessed via immunofluorescence,and neuronal apoptosis was evaluated by TUNEL assay.Serum and hippocampal levels of interleukin-6(IL-6),IL-1β,tumor necrosis factor-α(TNF-α)and nitric oxide(NO)were quantified using ELISA and Western blot.Gut microbiota diversity and serum untargeted metabolomics analyses were car-ried out employing 16S rRNA sequencing and LC-MS/GC-MS,respectively.Differential metabolites were screened,and key metabolic pathways were enriched using MetaboAnalyst 6.0.Spearman correlation analysis established relationships between gut microbiota,metabolites,and inflammatory factors.RESULTS:Model mice demonstrated increased escape latency(P<0.05 or P<0.01)and decreased platform crossings(P<0.01)compared with controls,which were reversed by PSP treatment(P<0.05 or P<0.01).Treatment with PSP substantially reduced IL-6,IL-1β,TNF-α and NO levels in se-rum and hippocampus(P<0.05 or P<0.01),diminished inflammatory infiltration,inhibited microglial activation,and re-duced neuronal damage.Gut microbiota analysis demonstrated that PSP increased Lactobacillus and Bacteroides abun-dance while reducing Alistipes(P<0.05).Metabolomics identified 15 differential metabolites(including betaine,kyotor-phin and ε-caprolactam)and highlighted the significance of alanine,aspartate and glutamate metabolism pathways.Spear-man analysis revealed that abundance of Alistipes and Bacteroides were positively correlated with IL-1β(P<0.05),while abundance of Lactobacillus was negatively correlated with inflammatory factors(P<0.05 or P<0.01).Key metabolites(be-taine,kyotorphin,ε-caprolactam,trans-cinnamate,cis-zeatin and galactitol)showed strong associations with inflamma-tion factors(P<0.05 or P<0.01).CONCLUSION:Treatment with PSP attenuates neuroinflammation through modula-tion of gut microbiota(Lactobacillus,Bacteroides and Alistipes),regulation of metabolites(betaine,kyotorphin and so on),and targeting amino acid metabolism pathways.

Objective:To evaluate the stability of percutaneous screw fixation for minimally invasive treatment of intra-articular calcaneal fractures using three-dimensional finite element analysis.Methods:CT scan was performed on the calcaneus of a normal adult for three-dimensional reconstruction. The DICOM data were imported into Mimics software to establish a model of a Sanders type IIB intra-articular calcaneal fracture. Based on the Essex-Lopresti classification of posterior facet morphology, the model was subdivided into two subtypes: tongue-type and depression-type. The calcaneus was divided into four fragments: sustentaculum tali, posterior tuberosity, anterior process (three points), and posterior articular surface (one surface). Two types of fixation methods, classical lateral anatomical plates and combinations of percutaneous screws, were simulated and performed. A three-dimensional finite element analysis was conducted by applying a stress combination of 420 N on the posterior subtalar articular surface, 200 N on the middle subtalar articular surface, and 300 N at the Achilles tendon insertion point. The maximum displacement and von Mises stress values of each bone fragment and implant were recorded to evaluate the biomechanical stability. For clinical validation, 34 patients with Sanders type IIB calcaneal fractures from Orthopedics Department of the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University were treated with percutaneous reduction and screw fixation using the following configurations.Results:Under simulated stress, the A4 group with medial support screws in the tongue-type fracture subgroup demonstrated minimal overall calcaneal displacement (0.22 mm) and internal fixation displacement (0.14 mm). For the depression-type, the B2 group with medial support screws showed lower maximum stress in the calcaneus and internal fixation, at 22.04 MPa and 41.14 MPa, respectively, along with the lowest overall displacement (0.14 mm). The peak stress of all groups of implants remained below the material yield strength. The A4 and B2 protocols were applied to 15 cases of tongue-type calcaneal fractures and 19 cases of collapse-type calcaneal fractures. At the final follow-up The American Orthopaedic Foot & Ankle Society ankle-hindfoot score scale was 86.1±5.82 and 87.2±5.18, respectively, while the visual analog scale for pain was 1.60±1.24 and 1.58±1.02, respectively.Conclusions:Percutaneous screw fixation provided reliable stability for Sanders type IIB calcaneal fractures. The fixation configuration incorporating a medial support screw offers superior biomechanical performance in both tongue-type and depression-type fractures, representing an optimized minimally invasive technique with strong clinical applicability.