1.Imaging Measurement of the Safe Distances of Acupuncture at Fengfu (GV 16) in Children Aged 4 to 8 Based on CT Three-Dimensional Reconstruction
Kun LI ; Tianyi WANG ; Xing WANG ; Zhijun LI ; Peng WU ; Yang YANG ; Yunteng HAO ; Hailong ZHAO ; Yuan MA ; Shaojie ZHANG
Journal of Traditional Chinese Medicine 2026;67(14):1523-1527
ObjectiveTo measure the distance from the surface of Fengfu (GV 16) to the deep important bony structures in children aged 4 to 8 years based on CT three-dimensional reconstruction technology, thereby providing imaging reference data for clinical acupuncture safe operations in terms of different age groups and needle insertion angles. MethodsCervical CT image data were collected from healthy children aged 4 to 8 years with five age groups (4-, 5-, 6-, 7-, 8-year-old groups), 20 cases in each group. The images were imported into Mimics 21.0 software for three-dimensional reconstruction. The straight-line distances from the skin model surface of the Fengfu (GV 16) to the first underlying bony barrier (such as the lower edge of the occipital bone, the posterior arch of the atlas vertebra) were measured at intervals of 5° on both the transverse section (0° ± 35°) and the sagittal section (40° upward to 40° downward on the diagonal). The correlation between the measured distance, age, and angle was analyzed. ResultsIn the transverse and sagittal sections, the measured distance from the skin surface to the underlying bone of Fengfu (GV 16) at each angle increased with age. In the transverse section, the increase was relatively small within the 0° to 20° angle range, whereas a more pronounced increase was observed when the angle exceeded 20°; at measurement angles of 30° to 35°, the distance of the skin surface to the bone at Fengfu (GV 16) in the 7- and 8-year-old groups was significantly greater than that in the 4-year-old group (P<0.05). In the sagittal section, the measured distance from the skin surface to the bone at Fengfu (GV 16) was shortest and changed greatly at oblique upward angles of 15° to 40° within each age group, and increased markedly at near-vertical angles of 0° to 10°; it was longest at oblique downward angles of -40° to -5° and showed relatively gradual changes. ConclusionThis study obtained the imaging distance data from Fengfu (GV 16) to the surrounding bony structures in children aged 4 to 8 years through three-dimensional modeling, finding that this distance has clear age and angle dependence, which can provide quantitative evidence for developing individualized and precise safe acupuncture schemes at Fengfu (GV 16) in pediatric clinical practice.
2.Imaging Measurement of the Safe Distances of Acupuncture at Fengfu (GV 16) in Children Aged 4 to 8 Based on CT Three-Dimensional Reconstruction
Kun LI ; Tianyi WANG ; Xing WANG ; Zhijun LI ; Peng WU ; Yang YANG ; Yunteng HAO ; Hailong ZHAO ; Yuan MA ; Shaojie ZHANG
Journal of Traditional Chinese Medicine 2026;67(14):1523-1527
ObjectiveTo measure the distance from the surface of Fengfu (GV 16) to the deep important bony structures in children aged 4 to 8 years based on CT three-dimensional reconstruction technology, thereby providing imaging reference data for clinical acupuncture safe operations in terms of different age groups and needle insertion angles. MethodsCervical CT image data were collected from healthy children aged 4 to 8 years with five age groups (4-, 5-, 6-, 7-, 8-year-old groups), 20 cases in each group. The images were imported into Mimics 21.0 software for three-dimensional reconstruction. The straight-line distances from the skin model surface of the Fengfu (GV 16) to the first underlying bony barrier (such as the lower edge of the occipital bone, the posterior arch of the atlas vertebra) were measured at intervals of 5° on both the transverse section (0° ± 35°) and the sagittal section (40° upward to 40° downward on the diagonal). The correlation between the measured distance, age, and angle was analyzed. ResultsIn the transverse and sagittal sections, the measured distance from the skin surface to the underlying bone of Fengfu (GV 16) at each angle increased with age. In the transverse section, the increase was relatively small within the 0° to 20° angle range, whereas a more pronounced increase was observed when the angle exceeded 20°; at measurement angles of 30° to 35°, the distance of the skin surface to the bone at Fengfu (GV 16) in the 7- and 8-year-old groups was significantly greater than that in the 4-year-old group (P<0.05). In the sagittal section, the measured distance from the skin surface to the bone at Fengfu (GV 16) was shortest and changed greatly at oblique upward angles of 15° to 40° within each age group, and increased markedly at near-vertical angles of 0° to 10°; it was longest at oblique downward angles of -40° to -5° and showed relatively gradual changes. ConclusionThis study obtained the imaging distance data from Fengfu (GV 16) to the surrounding bony structures in children aged 4 to 8 years through three-dimensional modeling, finding that this distance has clear age and angle dependence, which can provide quantitative evidence for developing individualized and precise safe acupuncture schemes at Fengfu (GV 16) in pediatric clinical practice.
3.Analysis of the change trend in the burden of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021
Jiachen WANG ; Siyi HE ; Mengdi CAO ; Yi TENG ; Qianru LI ; Nuopei TAN ; Yujie WU ; Tingting ZUO ; Tianyi LI ; Yuanjie ZHENG ; Wanqing CHEN
Chinese Journal of Digestive Surgery 2025;24(2):213-222
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.
4.Analysis of the change trend in the burden of 5 common malignant tumors of digestive system in the Chinese population from 1990 to 2021
Jiachen WANG ; Siyi HE ; Mengdi CAO ; Yi TENG ; Qianru LI ; Nuopei TAN ; Yujie WU ; Tingting ZUO ; Tianyi LI ; Yuanjie ZHENG ; Wanqing CHEN
Chinese Journal of Digestive Surgery 2025;24(2):213-222
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.
5.Finite element analysis of treatment for Sanders type IIB intra-articular calcaneal fracture by percutaneous screws
Yixuan CHEN ; Jiachen WU ; Chang LIU ; Tianyi WU ; Shang GUO ; Jiangyu CAI ; Ting WANG ; Mingjie TANG ; Zhongmin SHI ; Xin MA
Chinese Journal of Orthopaedics 2025;45(19):1241-1250
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.
6.Triangular Wave tACS Improves Working Memory Performance by Enhancing Brain Activity in the Early Stage of Encoding.
Jianxu ZHANG ; Jian OUYANG ; Tiantian LIU ; Xinyue WANG ; Binbin GAO ; Jinyan ZHANG ; Manli LUO ; Anshun KANG ; Zilong YAN ; Li WANG ; Guangying PEI ; Shintaro FUNAHASHI ; Jinglong WU ; Jian ZHANG ; Tianyi YAN
Neuroscience Bulletin 2025;41(7):1213-1228
Working memory is an executive memory process that includes encoding, maintenance, and retrieval. These processes can be modulated by transcranial alternating current stimulation (tACS) with sinusoidal waves. However, little is known about the impact of the rate of current change on working memory. In this study, we aimed to investigate the effects of two types of tACS with different rates of current change on working memory performance and brain activity. We applied a randomized, single-blind design and divided 81 young participants who received triangular wave tACS, sinusoidal wave tACS, or sham stimulation into three groups. Participants performed n-back tasks, and electroencephalograms were recorded before, during, and after active or sham stimulation. Compared to the baseline, working memory performance (accuracy and response time) improved after stimulation under all stimulation conditions. According to drift-diffusion model analysis, triangular wave tACS significantly increased the efficiency of non-target information processing. In addition, compared with sham conditions, triangular wave tACS reduced alpha power oscillations in the occipital lobe throughout the encoding period, while sinusoidal wave tACS increased theta power in the central frontal region only during the later encoding period. The brain network connectivity results showed that triangular wave tACS improved the clustering coefficient, local efficiency, and node degree intensity in the early encoding stage, and these parameters were positively correlated with the non-target drift rate and decision starting point. Our findings on how tACS modulates working memory indicate that triangular wave tACS significantly enhances brain network connectivity during the early encoding stage, demonstrating an improvement in the efficiency of working memory processing. In contrast, sinusoidal wave tACS increased the theta power during the later encoding stage, suggesting its potential critical role in late-stage information processing. These findings provide valuable insights into the potential mechanisms by which tACS modulates working memory.
Humans
;
Memory, Short-Term/physiology*
;
Male
;
Female
;
Young Adult
;
Transcranial Direct Current Stimulation/methods*
;
Brain/physiology*
;
Adult
;
Electroencephalography
;
Single-Blind Method
7.Obesity-related genes and genetic susceptibility to gastric cancer
Wenhui WU ; Shiyun DING ; Jingrao LI ; Ji ZHENG ; Jianing MAO ; Tianyi ZHU ; Yiling WU ; Ruoxin ZHANG
Shanghai Journal of Preventive Medicine 2025;37(7):569-580
ObjectiveTo explore the effects of genetic variation of obesity-related biological pathways and gene-obesity interactions on the incidence of gastric cancer, so as to better understand the pathogenesis of gastric cancer and help identify high-risk populations for individualized prevention of gastric cancer. MethodsA case-control study based on the Shanghai Suburban Adult Cohort and Biobank study (SSACB) was conducted on the cases with gastric cancer. A total of 267 cases with gastric cancer and 267 healthy controls matched 1∶1 by age and gender using propensity score were included in the study. After genome-wide genotyping, quality control and imputation, 19 250 single nucleotide polymorphism (SNP) sites from 115 genes in 4 obesity-related biological pathways were extracted. Univariate and multivariate logistic regression analyses were used to evaluate the association between these SNP sites and the risk of gastric cancer, and false positive report probability (FPRP) was used for multiple test correction.Data from Biobank Japan (BBJ) and FinnGen public accessible databases were used to validate significant SNP sites. For validated sites, expression quantitative trait loci (eQTL) analysis and differentially expressed genes analysis were further performed. Additive and multiplicative interactions were used to evaluate the gene-obesity interactions on the incidence of gastric cancer. Additive interaction evaluation indicators included relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (SI), while multiplicative interaction evaluation indicators include ORGxE and Pinter. ResultsA total of 41 SNP sites were significantly associated with the onset of gastric cancer (Padj<0.05, FPRP0.1<0.1), among which 7 groups of haplotype blocks were formed. ACACB/ rs2268401 [SSACB: P=0.005, BBJ: P=0.049], HRAS/ rs12785860 (SSACB: P<0.001, FinnGen: P=0.045), and PTPN1/ rs6095985 (SSACB: P<0.001, FinnGen: P=0.023) were significantly associated with the risk of gastric cancer after validation in different populations. Among which, the G allele of HRAS/ rs12785860 was correlated with the downregulation of HRAS mRNA expression (P<0.001), and the expression level of HRAS in gastric cancer tissues was higher than that in adjacent normal tissues (P<0.001). Additionaly, JAK1/rs11208559 showed a positive additive interaction with waist circumstance (WC) on the risk of gastric cancer [RERI=2.29(0.06~4.53), AP=0.57(0.23~0.90), SI=4.03(2.20~5.87)]. ConclusionObesity-related biological pathway SNP sites and their haplotypes are associated with the risk of gastric cancer, suggesting that genetic variations in obesity pathways may affect gastric cancer. The HRAS/ rs12785860 is significantly associated with downregulation of HRAS gene expression, which may serve as a potential genetic marker for gastric cancer. JAK1/rs11208559 interacts with obesity additively on the risk of gastric cancer. Individuals with GC+CC genotypes and pre-central or central obesity have an increased risk of gastric cancer, providing clues and evidences for individualized prevention of gastric cancer.
8.Corrigendum: Comparative analysis of cancer statistics in China and the United States in 2024.
Yujie WU ; Siyi HE ; Mengdi CAO ; Yi TENG ; Qianru LI ; Nuopei TAN ; Jiachen WANG ; Tingting ZUO ; Tianyi LI ; Yuanjie ZHENG ; Changfa XIA ; Wanqing CHEN
Chinese Medical Journal 2025;138(10):1260-1260
9.Finite element analysis of treatment for Sanders type IIB intra-articular calcaneal fracture by percutaneous screws
Yixuan CHEN ; Jiachen WU ; Chang LIU ; Tianyi WU ; Shang GUO ; Jiangyu CAI ; Ting WANG ; Mingjie TANG ; Zhongmin SHI ; Xin MA
Chinese Journal of Orthopaedics 2025;45(19):1241-1250
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.
10.Ilizarov external fixation technique combined with limited osteotomy for post-traumatic equinovarus deformity.
Tianyi WU ; Yixuan CHEN ; Guangyi LI ; Yu MIU ; Zhongmin SHI
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(8):982-988
OBJECTIVE:
To evaluate the effectiveness of correcting post-traumatic equinovarus deformity using Ilizarov external fixation technique combined with limited osteotomy.
METHODS:
A retrospective analysis was conducted on clinical data from 29 patients with post-traumatic equinovarus deformity treated between July 2018 and March 2023. The cohort included 18 males and 11 females, with ages ranging from 15 to 57 years (mean, 24.3 years). All patients exhibited ankylosed ankle joints with equinovarus deformity. During surgery, external fixators were installed according to Ilizarov pinning principles, and minimally invasive osteotomy was performed at the ankle joint. Concurrently, soft tissue release was achieved via minimally invasive Achilles tendon lengthening. Postoperatively, multiplanar deformity correction was accomplished through gradual adjustment of the external fixator. The fixator was removed after bony union at the osteotomy site, followed by bracing. The surgical duration, intraoperative blood loss, fixator wear time, and complications were recorded. Postoperative outcomes included assessment of deformity correction and bony union at the osteotomy site. Functional improvement and pain relief were evaluated using pre- and post-operative scores from the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score and visual analogue scale (VAS) score.
RESULTS:
All 29 patients were followed up 12-24 months (mean, 18 months). The mean surgical duration was 85.6 minutes, with a mean intraoperative blood loss of 110 mL. Full deformity correction was achieved within 26-80 days (mean, 40.7 days) through progressive fixator adjustments. At correction completion, all ankles restored to a neutral or 5°-10° dorsiflexed position with plantigrade foot function. Superficial pin tract infections occurred in 3 patients (10.3%), resolved with local wound care, enhanced nursing, and oral antibiotics. No deep or systemic infections was observed. One patient sustained a calcaneal half-pin fracture due to a fall during fixator wear, but no bone fragment displacement occurred. No vascular or neurological complication was reported. Complete bony union was achieved at all osteotomy sites without nonunion. At last follow-up, the AOFAS ankle-hindfoot score improved from preoperative 42.7±8.7 to postoperative 65.7±9.3, and the VAS score decreased from preoperative 4.5±1.3 to postoperative 2.5±1.1, with significant differences ( P<0.05). Functional outcomes were rated as excellent in 14 cases, good in 13 cases, fair in 1 case, and poor in 1 case, with an excellent and good rate of 93.1%.
CONCLUSION
The progressive correction strategy combining Ilizarov external fixation technique with limited foot osteotomy effectively corrects post-traumatic equinovarus deformity while preserving soft tissue integrity. This method is associated with minimal, largely controllable complications and achieves alignment stability and fusion outcomes comparable to traditional open surgery, making it an effective treatment for complex foot and ankle deformities.
Humans
;
Male
;
Female
;
Osteotomy/methods*
;
Adult
;
Retrospective Studies
;
Ilizarov Technique
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Middle Aged
;
Adolescent
;
External Fixators
;
Young Adult
;
Treatment Outcome
;
Ankle Joint/surgery*
;
Clubfoot/etiology*
;
Minimally Invasive Surgical Procedures/methods*

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