Elderly hip fracture (HF) patients are at very high risk of developing deep vein thrombosis (DVT), which increases their perioperative mortality. However, data focusing on the admission prevalence of DVT in elderly Chinese patients with hip fracture are limited. Venography and ultrasonography are not suitable for most elderly HF patients; there is also controversy about the prognostic value of D-dimer in elderly patients. Thus, our primary goal was to clarify the prevalence of and risk factors for DVT in elderly Chinese HF patients at admission. Our secondary goal was to evaluate the diagnostic value of a new predictor of DVT based on the risk factors for elderly HF patients. This retrospective study was conducted in the West China Hospital, Sichuan University. Between January 2015 and January 2017, 248 elderly Chinese HF patients (> 60 years) were enrolled in this study. The subjects were diagnosed with DVT using ultrasonography or venography. All the patients’ clinical data were obtained, including demographic variables, medical history, comorbidities, and laboratory results. A stepwise multiple logistic regression analysis was used to identify the risk factors contributing to the occurrence of DVT. The value of the new DVT predictor was calculated using a formula based on the coefficient regression and independent variables. A receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic value of different factors. Of the study patients, 74 (29.8%) were diagnosed with DVT, including sixty-five (87.8%) with distal peripheral, five (6.8%) with proximal central and four (5.4%) with mixed DVT. A multivariate logistic regression analysis showed that five risk factors increased the occurrence of DVT at admission, including gender, age, time from injury to admission, fibrinogen, and D-dimer. The new DVT predictor was calculated using the following formula: 1.131× (female = 1, male = 0) + 0.071 × age (years) + 0.571 × time from injury to admission (days) + 1.028 × fibrinogen(g/L) + 0.123 × D-dimer(g/L). The diagnostic value of the new predictor was highest among those risk predictors whose AUC (area under the ROC curves) value was 0.852. The results of this study revealed a high prevalence of DVT in elderly Chinese HF patients at admission. Moreover, the new predictor, based on risk factors, was a good method to improve the diagnosis of DVT.

Background: Segmental bone defects caused by trauma, tumors, or infection are a serious challenge for orthopedists in the world. Recent developments in tissue engineering have provided a new treatment for segmental bone defects. Urine-derived stem cells (USCs) can be obtained noninvasively and might be a new kind of seed cells used in bone tissue regeneration. Therefore, the first aim of the present study was to investigate the biological characteristics of USCs. The second aim of the present study was to study the osteogenic effect of surface mineralized biphasic calcium phosphate ceramics (BCPs) loaded with USCs in vitro and in vivo. Methods: We isolated USCs from the urine of healthy adult donors and evaluated the biological characteristics of USCs in vitro. We mineralized the surface of BCPs by simulated body fluid (SBF). Cell adhesion and proliferation of USCs on the surface mineralized BCPs were evaluated. Osteogenic proteins and genes of USCs on the surface mineralized BCPs were texted by enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR) assay. Critical-sized segmental bone defects model in New Zealand white rabbits were established and randomly divided into 4 groups (surface mineralized BCPs loaded with USCs, BCPs loaded with USCs, surface mineralized BCPs, and BCPs) based on the implant they received. The therapeutic efficacy of the scaffolds in a large bone defect at post-implantation was evaluated by imaging and histological examination. Results: USCs isolated in our study expressed stem cell-specific phenotypes and had a stable proliferative capacity and multipotential differentiation capability. Surface mineralized BCPs promoted osteogenic proteins and genes expression of USCs without affecting the proliferation of USCs. After 10 weeks, the amount of new bone formation was the highest in the group of surface mineralized BCPs loaded with USCs. Conclusion: USCs, from non-invasive sources, have good application prospects in the field of bone tissue engineering. Surface mineralized BCPs can significantly enhance osteogenic potential of USCs without changing biological characteristics of BCPs. Surface mineralized BCPs loaded with USCs are effective in repairing of critical-sized segmental bone defects in rabbits.