Developmental dysplasia of the hip (DDH) is a congenital or developmental deformation of the hip joint, which may require a high number of surgical interventions. It has been indicated that 3D printing may be used to simulate a fractured pelvis to facilitate the fixation of plates during the surgical procedure. In the present double-blinded randomized clinical trial, the utility of the 3D-printed pelvis model, comprising 3D reconstruction, reverse engineering and rapid prototyping, in the treatment of DDH was evaluated with 3D CT as control. The value of the 3D-printed pelvis model in the surgical management and development of a strategy for an individualized operation for DDH using osteotomy simulation was also assessed. The results indicated that use of the 3D-printed pelvis model increased the success rate of the operation with a shortened surgery time and post-operative recovery time for DDH patients. In addition, the application of the 3D-printed pelvis model allowed for more efficient surgical management of DDH than 3D CT and promoted post-operative recovery of the DDH patients. Pre-operative planning using the 3D-printed pelvis model was feasible for DDH patients. Furthermore, few patients exhibited delayed incision healing, wound infection or nonunion in the DDH group with osteotomy simulation using the 3D-printed pelvis model or 3D-CT. In conclusion, the present study indicated that the 3D-printed pelvis model, including 3D reconstruction, reverse engineering and rapid prototyping, constitutes an efficient tool for pelvic osteotomy simulation, which improves personalized pre-operative planning by providing a visual and accurate osteotomy model for patients with DDH (Chinese Trial Registry No. KCT0012374).

Bone graft defects may lead to dysfunction of bone regeneration and metabolic disorders of bone mesenchymal stem cells (BMScs). Puerarin has demonstrated pharmacological activities in the treatment of human metabolic diseases. The purpose of the present study was to investigate the role of puerarin and to explore its possible protective mechanism of action in rats with bone grafts. A bone graft rat model was established using bone grafting surgery and the rats received puerarin or PBS. Reverse transcription-quantitative PcR, western blot, TUNEL, immunofluorescence and immunohistochemistry assays were used to analyze the beneficial effects of puerarin on bone repair. The results demonstrated that puerarin effectively ameliorated pathological graft bone defects, decreased bone loss and apoptosis of BMScs, promoted BMSc proliferation and differentiation, and increased bone mass and the parameters of bone formation in rats with bone grafts. Puerarin decreased the levels of pro-inflammatory cytokines [tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-17A, IL-6 and transforming growth factor (TGF)-β1] and increased the levels of anti-inflammatory cytokines (IL-2 and IL-10) in the serum compared with the PBS group. Puerarin treatment was associated with lower serum alanine transaminase, glutamic oxaloacetic transaminase, γ-glutamyl transferase, alkaline phosphatase, direct bilirubin and total bilirubin levels compared with those in the PBS group in experimental rats. The expression of microRNA-155-3p (miR-155-3p) was upregulated, whereas that of p53, TNF-α and signal transducer and activator of transcription (STAT)1 was downregulated in BMSc cultures of puerarin-treated rats.In vitro assay demonstrated that knockdown of miR-155-3p increased p53, TNF-α and STAT1 expression in BMScs, and blocked puerarin-regulated p53/TNF-α/STAT1 signaling. Most importantly, miR-155-3p knockdown inhibited puerarin-regulated apoptosis, proliferation and differentiation of BMScs. Moreover, the results demonstrated that puerarin regulated vascular endothelial growth factor expression via the miR-155-3p signaling pathway. In conclusion, the results of the present study demonstrated that the upregulation of miR-155-3p induced by puerarin promoted BMSc differentiation and bone formation and increased bone mass in rats with bone grafts, thereby supporting the potential application of puerarin in the prevention of bone graft defects.

Background: Osteosarcoma (OS) is the primary malignant bone tumor that most commonly affects children, adolescents, and young adults. is involved in tumor metastasis and may be a prognostic marker for patients with cancer. The aim of the present study was to explore the role of miR-34a in patients with OS. The underlying associations between miR-34a expressions and metastasis, recurrence as well as and prognosis were comprehensively analyzed in OS patients.Methods: Reverse transcriptase quantitative PCR (RT-qPCR) was used to investigate serum level of miR-34a between clinical OS patients (n = 162) and age-matched healthy controls (n = 162). Expression of miR-34a in OS tissues and adjacent tissues was analyzed using RT-qPCR. RT-qPCR was used to compare the serum level of miR-34a in patients with OS before and after chemotherapy. Multivariate Cox-regression analysis was used to analyze the association between serum level of miR-34a and chemotherapy resistance, overall survival, as well as recurrence and prognosis of OS patients. Five-year recurrence and survival were estimated using Kaplan-Meier curves.Results: Serum level of miR-34a was downregulated in OS patients (n = 86) compared to age-matched healthy controls (n = 86). Expression of miR-34a was downregulated in OS tissue compared to adjacent tissues in clinical patients. The expression of serum miR-34a before and after chemotherapy was positively correlated with the expression of miR-34a in the corresponding tissues. Expression of miR-34a was higher in the group where chemotherapy was effective than that patient where chemotherapy was ineffective. Expression of miR-34a was negatively associated with chemotherapy resistance of OS patients. High serum levels of miR-34a were associated with longer overall survival in OS patients and lower metastasis. Multivariate Cox-regression analysis identified miR-34a serum level with potential prognostic significance. Conclusion:The expression level of serum miR-34a in patients with OS is closely related to the chemotherapy resistance, metastasis, recurrence, and survival of osteosarcoma, which can be used as one of the potential biomarkers and prognosis for the treatment of OS patients. Therefore, miR-34a may be a potential molecular for prediction of the efficacy of chemotherapy and prognosis in OS patients.Abbreviations: ANBT = adjacent normal bone tissues, miR-34a = microRNA-34a, OS = osteosarcoma, RT-qPCR = reverse transcriptase quantitative PCR.

Background: We aimed to use the finite element method to simulate the biomechanical effects of bone cement on the treatment of unstable intertrochanteric fractures with different degrees of osteoporosis using proximal femoral nail anti-rotation (PFNA) to provide personalized treatment plans for patients with type 31-A3.3 intertrochanteric fractures based on the AO Foundation/Orthopaedic Trauma Association classification. Methods: A finite element model of a normal right femur was created from CT images using related finite element analysis software, and its effectiveness was verified. In the experimental group, 12 types of fracture models with different degrees of osteoporosis were fixed using PFNA, while in the control group, 12 types of osteoporotic fracture models were fixed using bone cement augmented PFNA. A 700 N force was applied to the femoral head in a direction that simulated the direction of load-bearing while standing. The differences in the maximum displacement of the femur, PFNA, femoral stress, and varus angle between the two groups were observed and compared in ANSYS software. Results: Compared with the common PFNA model, the femoral head displacement, PFNA displacement, and varus angle of the femoral head were significantly smaller in the bone cement augmented PFNA model. However, the maximum stress in the femur was significantly increased. Compared with the experimental group, the change rate of femoral head displacement, PFNA displacement, and varus angle decreased from 2.94% to 5.89%, 3.23% to 4.79%, and 0.41% to 8.51% with increase in the degree of femur osteoporosis. The maximum stress change rate of the femur increased from 12.2% to 5.74%. Conclusion: Common PFNA for treatment of A3.3 intertrochanteric fracture is likely to fail in severe osteoporosis, and the varus angle and displacement can be significantly reduced with cement reinforcement. Therefore, PFNA internal fixation with bone cement should be considered for treatment of severe osteoporosis. When used in mild osteoporosis, bone cement increases the stress at the joint between the screw blade and the main nail; therefore, the use of PFNA alone should be considered for treatment in such cases to increase the service life of internal fixation devices.