Glucocorticoids could induce injury and apoptosis of bone microvascular endothelial cells (BMECs) in the femoral head, which is associated with the development of osteonecrosis and osteoporosis. Icariin is a prenylated flavonol glycoside isolated from Epimedium brevicornum, serving as the main active pharmaceutical constituent to treat bone loss. Currently, the impact of the autocrine activity of extracellular vesicles (EVs) induced by icariin on the glucocorticoid-induced injury of BMECs is still to be confirmed. In this study, EVs were isolated from BMECs treated with and without icariin by super-speed centrifugation. Although icariin treatment would not significantly change the size and total protein content of BMECs-derived EVs, expression of EVs-carried vascular endothelial growth factor (VEGF) and transforming growth factor β1 (TGF-β1) was enhanced and numerous miRNAs involved in cell proliferation and apoptosis were upregulated (e.g., hsa-miR-1469 and hsa-miR-133a-5p) or downregulated (e.g., hsa-miR-10b-5p) (p < 0.05). A total of 29 differentially expressed inflammatory factors were detected between the EVs secreted by BMECs from the Icariin-treated group and the Model group. The EVs secreted by BMECs could improve cell viability, decrease cell apoptosis, and promote cell migration and angiogenesis under the intervention of glucocorticoids. Meanwhile, icariin intervention could reinforce these protective effects of BMECs-derived EVs. To sum up, the present study indicates that icariin acts as a promising candidate for treating glucocorticoid-induced injury of BMECs and bone diseases, partially through the autocrine activity of EVs. In vivo or animal studies are still required to better understand the function of BMECs-derived EVs.

Bosworth ankle fracture-dislocation is rare, known to be an irreducible type of ankle injury, with a high incidence of complication. We present two cases of even rarer variants of Bosworth ankle fracture-dislocation. The first case is a type of supination external rotation adduction, and the second case is a type of supination external rotation adduction. These types have not been described before. In both of the cases we failed to achieve close reduction, and therefore proceeded with emergency surgeries, with open reduction and internal fixation. Both of the cases were performed with a postero-lateral approach to reduce the dislocations, and fix the fractures successfully. Unfortunately in one of the cases, acute compartment syndrome developed post-surgically. However, both cases showed good functional outcomes.

We report two cases of isolated Tillaux fracture and Volkmann fracture without other associated ankle fractures. The case of Tillaux fracture was a 15 year-old female who tripped and fell over during a 400 m hurdle running competition. Preoperative radiographs and CT scans showed Salter-Harris type III, an isolated Tillaux fragment, with more than 2 mm anterior and lateral displacement. Surgical stabilization of Tillaux fragment was performed via anterolateral minimal invasive approach with anatomic reduction of Tillaux fragment and two parallel cannulated screw fixation. The second case was a 21-year-old female who fell off a snowboard with her ankle in an odd position. Preoperative radiographs did not reveal any bony injuries. However, CT scans showed a Volkmann fracture at the posterolateral aspect of posterior malleolus without displacement. Non surgical management was given, after intraoperative imaging intensifier screening to confirm that there was no syndesmotic diastasis. The mechanism of injury and options of management are discussed in this report.

The incidence rate of PVNS, which is synovium tissue as nodules or pedunculated masses, is low however, the localized type is even less. We reported a case of the unusual properties of LPVNS located in the knee. A 32-year-old man presented to our clinic with pain and mechanic symptoms in his right knee. Magnetic resonance imaging (MRI) showed an intra-articular mass in the infrapatellar area of the knee adjacent to the Hoffa fat pad close to femoral trochlea groove. The mass was hypo intense in the T1 sequence and heterogeneously hypointense in the T2 sequence as well, which was considered as a local type of tenosynovial giant cell tumor (LPVNS). Excision was carefully performed without penetrating the tumor. The gross appearance of the tumor was yellow-reddish and brown in color. Histopathologic examination revealed pigmented villonodular synovitis of the local type. Localized Pigmented Villonodular Synovitis (LPVNS) is a very rare disease and it is silent and insidious, symptoms are non-specific, nevertheless, differentiation diagnosis should be keeping this entity in mind. Even though the LPVNS of the knee is an uncommon intra-articular presenttion, overlook this lesion based on imaging findings is an import approach for diagnosis of LPVNS, and arthroscopy assisted excision is an option for management of the LPVNS if doing it appropriately.