Objective:To summarize the 10 year clinical experience of treating tibiafibular fractures with rectangle shaped intramedullary nails(RIN). Methods:From January 1987 to December 1996, 4 682 cases (3 278 male and 1 404 female) of tibiafibular fractures from 9 hospitals were treated with RIN . Three kinds of reduction methods including open reduction, semi open reduction and closed reduction were used during operation. Results:Results showed 2 173 cases (62.89%) got excellent result, 947 got good (27.40%), 214 got moderate (6.19%), 121 got poor (3.50%). The total healing rate was 90.29%. Conclusion:RIN has excellent biological characteristics which can provide a flexible interfixation when treating tibiafibular fractures, and the operation is simple, it also can be used for severe open fractures. RIN is one of the good techniques in treating tibiafibular fractures.

OBJECTIVES: To explore the effect of hydrogel loaded with exosomes from Wharton's Jelly-derived mesenchymal stem cell (WJMSC) on wound healing. METHODS: Exosomes were extracted from WJMSC, and the morphology and size of WJMSC-derived exosomes (WEX) were analyzed by transmission electron microscopy and nanoparticle size analyzer, respectively. The surface markers CD9, CD81, and Calnexin of WEX were detected by Western blotting. Exosome-loaded alginate hydrogel (WEX-gel) was prepared; its morphology was studied by scanning electron microscope, and its rheological behavior was examined by a rheometer. The in vitro drug release performance of WEX-gel was investigated by BCA method. RAW264.7 cells were treated with alginate hydrogel, WEX and WEX-gel, respectively; and the expression of CD86 and CD206 in macrophages was detected by flow cytometry. A full-thickness skin wound model was established in mice; the model mice were randomly divided into blank control group, WEX control group and WEX-gel group, and PBS, WEX and WEX-gel were applied to the wound area of mice, respectively. On day 3, the skin tissue of mice was excised, and the antibacterial effect of WEX hydrogel was evaluated by plate counting. On day 15, the mice were euthanized and the percentage of residual wounds was calculated. The histological changes of the skin wound were observed after hematoxylin and eosin (HE) and Masson stainings. The expression of CD86, CD206, CD31 and vascular endothelial growth factor (VEGF) in the skin wound tissue was detected by immunohistochemistry. RESULTS: Exosomes were successfully extracted from WJMSC. WEX-gel presented a regular three-dimensional network structure, good rheology and controlled drug release performance. WEX-gel promoted the polarization of RAW264.7 cells from the M1 phenotype to M2 phenotype in vitro. The residual wound percentage in blank control group, WEX control group and WEX-gel group were (27.5±3.4)%, (15.3±1.2)% and (7.6±1.1)%, respectively (P<0.05). The antibacterial property of WEX-gel is better than that of WEX (P<0.05). The dermis thickness, the number of new hair follicles, and the rate of collagen deposition in the WEX-gel group were significantly higher than those in the other two groups (all P<0.05). The expression of CD206, CD31 and VEGF in skin wound tissue was higher and the expression of CD86 was lower in WEX-gel group than those in other two groups (all P<0.05). CONCLUSIONS WEX-gel can significantly promote wound healing in mice by regulating the polarization of macrophages.
Mice ; Animals ; Vascular Endothelial Growth Factor A ; Wharton Jelly ; Exosomes ; Hydrogels ; Wound Healing/physiology* ; Mesenchymal Stem Cells ; Anti-Bacterial Agents ; Alginates