Objective To study the effects of porous prothesis with radial gradient and homogenized structures on stress transmission in the tibia by using finite element method.Methods Based on the reverse engineering technology,the tibial model was constructed,and the bionic trabecular bone structure prosthesis with gradient change of pore edge diameter and the homogeneous bionic trabecular bone structure prosthesis were designed.The Vicon dynamic capture platform was used to obtain the human gait and the axial force of the tibia-femoral joint during flexion,which was imported into ANSYS Workbench as a boundary condition for mechanical performance analysis.Results In the case of proximal defect,the von Mises stress of the bone for prosthesis with radial gradient structure was increased by 3.68 MPa,and that in the case of distal defect was increased by 7.34 MPa.Compared with the homogenized prosthesis,the von Mises stress of the proximal and distal defects was decreased by 171 MPa and 190.4 MPa,respectively.Conclusions The stress of the radial gradient structure prosthesis diffuses from the outside to the middle high porosity area along the prosthesis,which can effectively transfer the tibial plateau load,reduce stress concentration of the prosthesis,improve bone stress and prolong service life of the prosthesis.This study provides a theoretical reference for clinical prosthesis replacement.

Objective:To investigate the clinical value of Delphian lymph node (DLN) metastasis (DLNM) in predicting regional lymph node involvement in patients with intrathyroidal papillary thyroid carcinoma (PTC).Methods:Clinical and pathological data from 345 consecutive patients with pathologically confirmed DLN status, who underwent initial surgical treatment at the Department of Surgical Oncology, First Affiliated Hospital of Zhejiang University School of Medicine between Jan 2020 and Dec 2022, were retrospectively analyzed.Results:DLNM was identified in 61 patients (17.7%). Univariate analysis revealed significant associations between DLNM and male sex, elevated preoperative thyroglobulin levels, larger tumor size, maximum tumor diameter >10 mm, bilateral lesions, multifocality, lymphovascular invasion, and lymph nodes metastases in pretracheal, paratracheal, and lateral cervical(all P ≤0.001). Elevated thyroglobulin antibody levels ( χ2=6.201, P=0.013) and Hashimoto's thyroiditis ( χ2=11.340, P<0.001) were protective factors for DLNM. Multivariate analysis identified male sex, lymphovascular invasion, pretracheal, and paratracheal lymph node metastases ( χ2=6.689, P=0.010; χ2=8.163, P=0.004; χ2=7.605, P=0.006; χ2=8.324, P=0.004) as independent risk indicators for DLNM. Patients with DLNM exhibited significantly higher risks of lymph nodes metastases in pretracheal ( χ2=27.307, P<0.001), paratracheal ( χ2=38.697, P<0.001), and lateral cervical ( χ2=36.459, P<0.001). Conclusion:DLNM demonstrates predictive value for both central compartment and lateral cervical lymph node metastases, warranting particular attention to meticulous dissection of the prelaryngeal region during surgery.

BACKGROUND: Death burden of stroke is severe with over one-third rural residents in China, but there is still a lack of specific national and high-quality reports on the urban-rural differences in stroke burden, especially for subtypes. We aimed to update the understanding of urban-rural differences in stroke deaths. METHODS: This is a descriptive observational study. Data from the national mortality surveillance system, which covers 323.8 million with 605 disease surveillance points (DSPs) across all 31 provinces, municipalities, and autonomous regions in China. All deaths from stroke as the underlying cause from 2015 to 2020 according to DSPs. Crude mortality rate and age-standardized mortality rate (ASMR) were estimated through DSPs. Average annual percentage change was used to explain the change in mortality rate. RESULTS: From 2015 to 2020, the majority of deaths from all stroke subtypes occurred in rural areas. There were significant differences between the changes of urban and rural ASMRs. On the whole, the changes in urban areas were evidently better, and the ASMR differences were basically expanding. Stroke ASMR in urban China decreased by 15.5%. The rural ASMR of ischemic stroke increased by 12.9%. The rural and urban ASMRs of intracerebral hemorrhage decreased by 24.9% and 27.4%, and those of subarachnoid hemorrhage decreased by 29.5% and 40.4%, respectively. The highest ASMRs of all stroke subtypes and the increasing trend of ischemic stroke ASMR make rural males the focus of stroke management. CONCLUSIONS The death burden of stroke varies greatly between urban and rural China. Rural residents face unique challenges.
Humans ; China/epidemiology* ; Stroke/mortality* ; Rural Population/statistics & numerical data* ; Male ; Female ; Urban Population/statistics & numerical data* ; Middle Aged ; Aged ; Aged, 80 and over ; Adult

ObjectiveTo dynamically observe the clinical symptoms and pathological changes in a rat model of vinorelbine-induced phlebitis via injection into the dorsalis pedis vein. MethodsTwenty-eight 11-week-old male SPF-grade SD rats were randomly divided into a model group (n=20) and a control group (n=8). The model group received a single injection of 0.1 mL vinorelbine solution (4 mg/mL) via the right hind limb dorsalis pedis vein, while the control group received an equal volume of normal saline via the same method. The occurrence and grading of phlebitis in both groups were observed and recorded daily. The volume of the injured limb was measured by the drainage method to calculate the swelling rate. The weight-bearing ratio of the injured limb was assessed using a bipedal balance pain meter, and the skin temperature of the injured limb was measured by infrared thermal imaging. These measurements were conducted for 9 consecutive days. Starting from day 1, three rats from the model group were euthanized every other day. A 1-cm segment of the vein extending proximally from the injection site was collected. Pathological changes in the vein tissue were examined by hematoxylin-eosin staining, and ultrastructural changes of the vascular endothelium were observed using scanning electron microscopy. ResultsCompared to the control group, the injected hindlimb of model rats showed redness and swelling on day 1, with the swelling rate peaking at (81.89±15.75) % on day 3 (P<0.001), then gradually alleviating and decreasing to (15.41±0.33) % by day 9 (P<0.01). Pain was observed in the affected limbs of model rats on day 1 and worsened markedly on day 3, with the weight-bearing ratio decreasing to (36.35±4.91)% (P<0.001). Meanwhile, the skin temperature of the lesion site increased, reaching (36.36±0.40) ℃ on day 5 (P<0.001). Both pain and fever returned to near normal levels by day 9. Phlebitis grading in the model group showed that 75.0% of rats were grade Ⅱ on day 1; grade Ⅲ and Ⅳ each accounted for 37.5% on day 3; from days 5 to 9, most rats exhibited cord-like veins, predominantly grade III. Venous tissue showed peripheral edema and inflammatory cell infiltration on day 1, which gradually progressed to intimal rupture, vessel wall thickening, and even lumen narrowing from day 3 to 9. The venous intima exhibited destruction of tight junctions between endothelial cells and adhesion of blood cells, progressing to roughened, wrinkled, and protruding intimal surfaces. ConclusionThe vinorelbine-induced phlebitis of dorsal foot vein in rat model is characterized by local redness, swelling, warmth, and pain from days 3 to 5, which largely resolve by day 9, although cord-like veins can still be observed. With disease progression, venous tissue develops edema, vessel wall thickening, and lumen narrowing. The venous intima shows rupture, roughening, and in some cases, complete loss.

ObjectiveTo dynamically observe the clinical symptoms and pathological changes in a rat model of vinorelbine-induced phlebitis via injection into the dorsalis pedis vein. MethodsTwenty-eight 11-week-old male SPF-grade SD rats were randomly divided into a model group (n=20) and a control group (n=8). The model group received a single injection of 0.1 mL vinorelbine solution (4 mg/mL) via the right hind limb dorsalis pedis vein, while the control group received an equal volume of normal saline via the same method. The occurrence and grading of phlebitis in both groups were observed and recorded daily. The volume of the injured limb was measured by the drainage method to calculate the swelling rate. The weight-bearing ratio of the injured limb was assessed using a bipedal balance pain meter, and the skin temperature of the injured limb was measured by infrared thermal imaging. These measurements were conducted for 9 consecutive days. Starting from day 1, three rats from the model group were euthanized every other day. A 1-cm segment of the vein extending proximally from the injection site was collected. Pathological changes in the vein tissue were examined by hematoxylin-eosin staining, and ultrastructural changes of the vascular endothelium were observed using scanning electron microscopy. ResultsCompared to the control group, the injected hindlimb of model rats showed redness and swelling on day 1, with the swelling rate peaking at (81.89±15.75) % on day 3 (P<0.001), then gradually alleviating and decreasing to (15.41±0.33) % by day 9 (P<0.01). Pain was observed in the affected limbs of model rats on day 1 and worsened markedly on day 3, with the weight-bearing ratio decreasing to (36.35±4.91)% (P<0.001). Meanwhile, the skin temperature of the lesion site increased, reaching (36.36±0.40) ℃ on day 5 (P<0.001). Both pain and fever returned to near normal levels by day 9. Phlebitis grading in the model group showed that 75.0% of rats were grade Ⅱ on day 1; grade Ⅲ and Ⅳ each accounted for 37.5% on day 3; from days 5 to 9, most rats exhibited cord-like veins, predominantly grade III. Venous tissue showed peripheral edema and inflammatory cell infiltration on day 1, which gradually progressed to intimal rupture, vessel wall thickening, and even lumen narrowing from day 3 to 9. The venous intima exhibited destruction of tight junctions between endothelial cells and adhesion of blood cells, progressing to roughened, wrinkled, and protruding intimal surfaces. ConclusionThe vinorelbine-induced phlebitis of dorsal foot vein in rat model is characterized by local redness, swelling, warmth, and pain from days 3 to 5, which largely resolve by day 9, although cord-like veins can still be observed. With disease progression, venous tissue develops edema, vessel wall thickening, and lumen narrowing. The venous intima shows rupture, roughening, and in some cases, complete loss.

Objective To investigate the application of transvaginal ultrasound(TVS),multimo-dal magnetic resonance imaging(MRI)and 18F-fluorodeoxyglucose positron emission computed tomo-graphy/computed tomography(18F-FDG PET/CT)in diagnosis of endometrial carcinoma(EC).Methods A total of 157 patients with endometrial cancer in our hospital were selected.The results of EC staging by multimodal MRI and transvaginal ultrasound and positive 18F-FDG PET/CT were recor-ded,and their results were compared with pathological results.Results The results of TVS showed 87 cases in stage Ⅰ,6 cases were misdiagnosed and 12 cases were missed diagnosis.In 55 cases of stage Ⅱ,12 cases were misdiagnosed and 8 cases were missed.In 15 cases of stage Ⅲ,2 cases were misdiagnosed without missed diagnosis.The results of multimodal MRI showed that 86 cases were mis-diagnosed in stage Ⅰ,3 cases were misdiagnosed and 10 cases were missed.In 58 cases of stage Ⅱ,10 cases were misdiagnosed and 3 cases missed diagnosis.There were 13 cases of stage Ⅲ with no missed diagnosis or misdiagnosis.The results of 18F-FDG PET/CT were positive in 145 cases and missed in 12 cases.Based on the golden standard of postoperative pathological staging,the accuracy of TVS di-agnosis of EC patients in stage Ⅰ was 87.10％(81/93),stage Ⅱ was 84.31％(43/51),and stage Ⅲ was 100％(13/13).Based on the golden standard of postoperative pathological staging,the accuracy of mul-timodal MRI in the diagnosis of EC patients was 89.25％(83/93)in stage Ⅰ,94.12％(48/51)in stageⅡ,and 100％(13/13)in stage Ⅲ.According to the pathological staging,145 EC positive cases were de-tected by 18F-FDG PET/CT,the accuracy rate was 92.36％(145/157).Conclusion 18F-FDG PET/CT has a high diagnostic accuracy in EC patients,TVS and multimodal MRI have a high value in the preoperative staging diagnosis of EC,and are worthy of clinical promotion.

This study evaluates the safety and early clinical outcomes of a novel 3D-printed titanium alloy "sleeve" component for revising fractured femoral stem prostheses in distal femoral megaprostheses without removing the fractured stem. The six patients included 2 males and 4 females, with an age range of 8-57 years. They were treated at Peking University People's Hospital between August 2020 and December 2023 and underwent revision surgery using the customized sleeve. A self-designed 3D-printed titanium alloy "sleeve" component was used for revision without removing the fractured stem, in the form of an external sleeve around the stem. Postoperative imaging was performed every three months to assess implant stability and bone integration. Functional outcomes were evaluated using the Musculoskeletal Tumor Society (MSTS)-93 score. All six patients successfully completed the surgery and follow-up, with surgical durations ranging from 120 to 230 minutes and intraoperative blood loss ranging from 150 to 800 ml. The follow-up period ranged from 6 to 46 months. At three months postoperatively, X-ray and CT imaging showed cortical bridging between the host bone and the "sleeve" component. By six months, full integration of the host cortical bone with the metal trabecular interface of the "sleeve" was observed. At the final follow-up, MSTS-93 scores ranged from 26 to 29 points, with no complications such as wound healing issues, implant loosening, fracture, infection, or degenerative arthritis. These findings suggest that 3D-printed titanium "sleeve" provide an effective, bone-preserving solution for femoral stem revision in oncologic megaprostheses, leading to favorable early stability and functional recovery.

Objective:To analyze the clinical efficacy of pasteurization-inactivated tumor bone replantation combined with intramedullary vascularized fibula for reconstructing bone defects after surgery for malignant bone tumors in children and adolescents.Methods:A retrospective analysis was performed on the data of 54 patients who underwent pasteurization-inactivated tumor bone replantation combined with intramedullary vascularized fibula reconstruction for bone defects after surgery for malignant bone tumors at the Bone and Soft Tissue Tumor Treatment Center of Peking University People's Hospital from September 2015 to September 2023. There were 39 males and 15 females, with an age of 12.4±5.6 years (range, 4 to 23 years). The tumor types included 33 cases of osteosarcoma, 19 cases of Ewing sarcoma, and 2 cases of soft tissue sarcoma. All cases were at Enneking stage IIB. The tumor locations were 30 cases in the femur, 19 cases in the tibia, 4 cases in the ilium, and 1 case in the humerus. The survival rate, bone healing time, tumor recurrence, and metastasis were observed. The limb function was evaluated using the Musculoskeletal Tumor Society (MSTS)-93 score.Results:All patients successfully completed the surgery and were followed up, with a follow-up time of 44.6±27.1 months (range, 12 to 96 months). The operation time was 527±132 min (range, 150 to 730 min), and the blood loss was 730±591 ml (range, 300 to 2,800 ml). The length of inactivated tumor bone was 16.5±4.5 cm (range, 9.1 to 24.0 cm), the defect length accounted for 43.4%±12.2% of the total length of the affected bone (range, 23.8% to 75.5%), the proximal osteotomy of the long bones in the extremities was 14.1±8.3 cm from the articular surface (range, 1.9 to 31.1 cm), the distal osteotomy was 9.4±6.2 cm from the articular surface (range, 1.7 to 22.9 cm), and the length of the harvested vascularized fibula was 18.0±4.0 cm (range, 11.0 to 26.4 cm). At the last follow-up, 51 patients were alive, including 47 with no evidence of tumor and 4 with tumor; 3 patients died of tumor progression. Local recurrence occurred in 5 patients, including 4 with soft tissue recurrence in the surgical area (3 underwent surgical resection and 1 received radiotherapy) and 1 with recurrence at the site of inactivated bone. Distant metastasis occurred in 11 patients, including 5 with lung metastasis only, 2 with bone metastasis only, and 4 with combined lung and bone metastasis. Among the 5 patients with lung metastasis only, lung metastases were resected, with 3 surviving with tumor, 2 surviving without tumor; the 2 patients with bone metastasis only underwent surgical resection of bone metastases, both surviving without tumor. Among the 4 patients with combined lung and bone metastasis, 3 died of tumor progression and 1 survived with tumor. The Kaplan-Meier curve showed a 5-year survival rate of 90.8%±6.2% and a 5-year recurrence-free and metastasis-free survival rate of 68.7%±7.9%. The osteotomy healing time at the diaphysis was 8.4±2.3 months (range, 4 to 13 months), the osteotomy healing time at the metaphysis was 5.9±1.7 months (range, 3 to 10 months), and the healing time between inactivated tumor bone and fibula was 6.4±2.0 months (range, 4 to 11 months). No nonunion occurred. The MSTS-93 score at the last follow-up was 94.4%±4.8% (range, 80% to 100%).Conclusion:Pasteurization-inactivated tumor bone replantation combined with intramedullary vascularized fibula reconstruction for bone defects after surgery for malignant bone tumors in children and adolescents has satisfactory clinical efficacy, high bone healing rate, and low rates of local recurrence and distant metastasis.

Objective:To evaluate the preliminary clinical efficacy of minimally invasive extendable prostheses in limb-salvage treatment for distal femoral osteosarcoma in children.Methods:A retrospective analysis was conducted on 36 children who underwent reconstruction of bone defects after distal femoral osteosarcoma resection with minimally invasive extendable prostheses at Peking University People's Hospital between December 2021 and December 2023. The cohort included 22 males and 14 females, with a mean age of 10.1±2.7 years (range: 4.3-14.3 years). Among them, 27 cases were primary tumor resections with post-resection bone defects of 17.4±3.2 cm (range: 13.5-25.0 cm), and 9 cases were revision surgeries. Preoperatively, femoral limb length discrepancy (LLD) was 29.6±14.3 mm (range: -1.2-55.0 mm), tibial LLD was 16.0±11.3 mm (range: -4.8-30.0 mm), and total lower limb LLD was 45.1±23.6 mm (range: -5.5-77.0 mm). The prosthesis was modular and compatible with existing tumor prosthesis components via taper connections. Lengthening was achieved by axial screw manual expansion through a 3-4 cm parapatellar arc incision, using a specialized wrench for adjustment. X-rays were performed pre-implantation, before and after each lengthening, and at the last follow-up to assess femoral, tibial, and total lower limb LLD, as well as extension length. At the final follow-up, limb function was assessed using the Musculoskeletal Tumor Society (MSTS)-93 score, and extension-related complications were analyzed.Results:All 36 children successfully underwent implantation and subsequent extension when indicated. The mean follow-up was 14.9±8.1 months (range: 6-31 months). Eleven patients underwent 16 lengthening procedures, with a mean of 1.5±0.8 per case (range: 1-3) and an average extension of 21.1±8.3 mm (range: 9.2-42.8 mm), achieving a total mean recovery of 31.0±16.1 mm (range: 10.4-61.7 mm). Two patients reached the maximum 5 cm extension capacity and underwent minor procedures to retract the extension device and secure the prosthesis. The remaining 25 patients did not require extension as their LLD was <2 cm. At the last follow-up, femoral, tibial, and total lower limb LLDs were 10.6±11.4 mm (range: -8.6-41.4 mm), 9.1±12.7 mm (range: -9.5-39.5 mm), and 20.1±21.0 mm (range: -10.4-72.5 mm), respectively. The mean MSTS-93 score for the 11 extended patients was 90.0%±12.7% (range: 80.0%-96.7%). Complications included two cases of aseptic loosening requiring revision, one transient peroneal nerve palsy after fixed-length filling, and three cases of prosthesis segment retraction due to excessive exercise. Retractions occurred at 9.1±3.3 months (range: 5.3-11.3 months) and were corrected during subsequent extensions without revision.Conclusions:Minimally invasive extendable prostheses allow individualized limb lengthening through small parapatellar incisions based on LLD and soft tissue tension. The extension mechanism is stable, and functional recovery is favorable.

Objective:To investigate the efficacy of two types of micro-focused ultrasound devices combined with botulinum toxin type A (BoNT-A) injection for facial rejuvenation.Methods:A retrospective study was conducted, including 60 female patients aged 28-70 (41.3±7.9) years, who received facial rejuvenation treatment at the Department of Plastic and Reconstructive Surgery, Zhongnan Hospital of Wuhan University, from April 2023 to April 2024. Patients were divided into two groups based on the treatment method: the control group (received only micro-focused ultrasound treatment, n=30) and the combined group (received both micro-focused ultrasound and BoNT-A injection, n=30). Additionally, patients were further categorized into four subgroups based on the type of micro-focused ultrasound device used: Peninsula Microultra? (PM) device group ( n=15), Intelligent Ultrasound? (IU) device group ( n=15), PM device + BoNT-A injection group ( n=15), and IU device + BoNT-A injection group ( n=15). The severity of facial wrinkles was assessed using the wrinkle severity rating scale (WSRS), the Merz aesthetic scale (MAS), and the global aesthetic improvement scale (GAIS) at baseline and 6 months post-treatment. Adverse event rates were also recorded. Results:At 6 months post-treatment, the combined group showed significantly lower WSRS and MAS scores than the control group (both P<0.001). No significant differences were found between the PM and IU device groups, or between the PM + BoNT-A and IU + BoNT-A groups regarding WSRS and MAS scores (all P>0.05). Self-reported GAIS improvement was 56.7% (17/30) for the control group and 80.0% (24/30) for the combined group, with the combined group showing superior results ( P=0.015). The physician-assessed GAIS improvement was 70.0% (21/30) for the control group and 96.7% (29/30) for the combined group, again with the combined group showing superior results ( P=0.007). No significant differences were found in self-reported or physician-assessed GAIS improvement between the PM and IU device groups, or between the PM + BoNT-A and IU + BoNT-A groups (all P>0.05). No severe adverse reactions, such as blisters, scabbing, purpura, bruising, scarring, peripheral facial paralysis, allergies, muscle weakness, dysphagia, or dysphonia, were observed in any patient. Conclusion:The combination of micro-focused ultrasound and BoNT-A injection for facial rejuvenation is more effective than micro-focused ultrasound alone, while there are no significant differences in efficacy between the two micro-focused ultrasound devices.