Objective To develop a predictive model integrating clinical features,deep learning(DL),and radiomics based on T2-weighted imaging for prenatal assessment of postpartum hemorrhage(PPH)risk in high-risk pregnant women.Methods A total of 538 pregnant women with ultrasound-reported high-risk placenta accrete were retrospectively enrolled and divided into training,internal test,and external test cohorts.A nnUNet model was trained for automatic placental segmentation.Univariate and multivariate analyses were conducted on clinical features to identify those associated with PPH.Quantitative radiomic features were extracted from the placental region,and a random forest model was developed to predict estimated blood loss(EBL)and PPH risk.A DenseNet-based multi-task DL model was trained to predict PPH risk,EBL,and placenta previa status.Finally,a DL-radiomics ensemble(DRE)model was constructed by integrating clinical features,DL outputs,and radiomics scores.Diagnostic performance was evaluated using the area under the receiver operating characteristic curve(AUC)and DeLong test.Results The DRE model achieved AUC values of 0.874(95%CI:0.792-0.951)and 0.836(95%CI:0.648-0.974)in the internal and external test cohorts,respectively,significantly outperforming the standalone clinical,DL,and radiomics models.Incorporation of EBL regression improved the performance of the PPH classification model,with the external test AUC increasing from 0.261-0.788 to 0.836.Conclusion The DRE model integrating DL and radiomics can efficiently predict PPH risk and assist in the clinical management of high-risk pregnancies.

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.

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.

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.

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.