Liposclerosing myxofibrous tumor of the distal femur: A case report.

Introduction: Liposclerosing myxofibrous tumor (LSMFT) is a rare benign fibro-osseous tumor that most frequently occurs in the proximal femur. The reported literature shows that the proximal femur, ilium, tibia, humerus, rib, and skull have occurred, but so far, the female distal femur has not been characterized in detail. This, we think, is the first single comprehensive case report of the female distal femur. To prevent misdiagnosis and overtreatment of this illness, it is critical for us to continue strengthening our knowledge of it and to add it to the differential diagnosis of the space-occupying lesion of the female distal femur. Case summary: Two months ago, a 55-year-old female patient was found to have a space-occupying lesion of the left distal femur and the pain symptom was aggravated. She underwent thorough curettage and bone grafting without additional treatment to relieve the current symptoms and determine the nature of the lesion in our hospital. The intraoperative specimens were submitted to the pathology laboratory for analysis, and the result was reported as LSMFT. And six months after the operation, the patient returned to our hospital for another x-ray examination and we found that she had recovered well without any signs of recurrence. The patient self-reported that she had now resumed her daily life without any uncomfortable symptoms. Conclusion: The incidence of LSMFT itself is relatively low, and the occurrence of the distal femur is even rarer. However, it is recommended to add LSMFT into the differential diagnosis of the occupying lesions of the distal femur. Once the diagnosis is made, thorough curettage and bone grafting without additional special treatment can achieve better postoperative outcomes. The patient gave her agreement after learning that information about the case will be submitted for publication.

Gene markers of fracture healing in early stage and the regulatory mechanism during the process using microarray analysis.

BACKGROUND: The aim of this study was to explore crucial markers and uncover the regulatory mechanisms of fracture healing in the early stage. METHODS: Gene expression profile of GSE45156 was downloaded, in which 3 fractured samples and 3 unfractured samples were used in our present study. Based on the threshold value, differentially expressed genes (DEGs) were selected between two kinds of samples using limma package in R. Enrichment analysis of these DEGs was performed by DAVID software. Furthermore, protein-protein interaction (PPI) network was established integrating information in STRING database, and visualized by Cytoscape software. RESULTS: We identified a set of 960 DEGs including 509 up-regulated and 451 downregulated genes. Biological processes involving RNA splicing and cell cycle were significantly enriched for the up-regulated genes such as Snrpd2, Eftud2, Plk1 and Bub1b, whereas skeletal system development and bone development processes were predominant for down-regulated genes like Ubc. In the constructed PPI network, all the five genes were the predominant nodes, of which Snrpd2 was linked to Eftud2, while Bub1b was to interact with Plk1. CONCLUSION: Five candidate genes crucial for indicating the process of fracture in early stage were identified. Eftud2, Snrpd2, Bub1b and Plk1 might function through the involvement of cell-cycle-related BP, while Ubc might influence the protein degradation during bone development. However, more experimental validations are needed to confirm these results.

Shock wave-induced ATP release from osteosarcoma U2OS cells promotes cellular uptake and cytotoxicity of methotrexate.

BACKGROUND: Osteosarcoma is the most prevalent primary malignant bone tumor, but treatment is difficult and prognosis remains poor. Recently, large-dose chemotherapy has been shown to improve outcome but this approach can cause many side effects. Minimizing the dose of chemotherapeutic drugs and optimizing their curative effects is a current goal in the management of osteosarcoma patients. METHODS: In our study, trypan blue dye exclusion assay was performed to investigate the optimal conditions for the sensitization of osteosarcoma U2OS cells. Cellular uptake of the fluorophores Lucifer Yellow CH dilithium salt and Calcein was measured by qualitative and quantitative methods. Human MTX ELISA Kit and MTT assay were used to assess the outcome for osteosarcoma U2OS cells in the present of shock wave and methotrexate. To explore the mechanism, P2X7 receptor in U2OS cells was detected by immunofluorescence and the extracellular ATP levels was detected by ATP assay kit. All data were analyzed using SPSS17.0 statistical software. Comparisons were made with t test between two groups. RESULTS: Treatment of human osteosarcoma U2OS cells with up to 450 shock wave pulses at 7 kV or up to 200 shock wave pulses at 14 kV had little effect on cell viability. However, this shock wave treatment significantly promoted the uptake of Calcein and Lucifer Yellow CH by osteosarcoma U2OS cells. Importantly, shock wave treatment also significantly enhanced the uptake of the chemotherapy drug methotrexate and increased the rate of methotrexate-induced apoptosis. We found that shock wave treatment increased the extracellular concentration of ATP and that KN62, an inhibitor of P2X7 receptor reduced the capacity methotrexate-induced apoptosis. CONCLUSIONS: Our results suggest that shock wave treatment promotes methotrexate-induced apoptosis by altering cell membrane permeability in a P2X7 receptor-dependent manner. Shock wave treatment may thus represent a possible adjuvant therapy for osteosarcoma.

Incidence and risk factors for venous thromboembolism following surgical treatment of fractures below the hip: a meta-analysis.

Venous thromboembolism (VTE) is a common complication after surgical treatment of fractures, which is associated with significant morbidity and mortality. Identifying the risk factors for VTE is important for preventive strategies to reduce the incidence of VTE. Therefore, we conducted a meta-analysis to evaluate the incidence of VTE and the risk factors influencing the development of VTE in patients who underwent surgery for fractures below the hip. PubMed, Embase, Web of Science, SinoMed (Chinese BioMedical Literature Service System, China) and CNKI (National Knowledge Infrastructure, China) databases were systematically searched to identify cohort or case-control studies that investigated the incidence and risk factors for VTE following surgical treatment of fractures below the hip. VTE risk ratios (RRs) were pooled by use of a fixed-effect model or a random-effect model, depending on the heterogeneity among the included studies. Heterogeneity between the studies was assessed by I2 statistics. Twenty-three studies with a total of 191 294 patients who met the inclusion criteria were included in this meta-analysis. Our results demonstrated that age (≥60 years) (RR = 1·85, 95% confidence interval (CI): 1·34, 2·55; P = 0·000), previous VTE(RR = 5·25, 95% CI: 2·77, 9·96; P = 0·000), heart failure (RR = 1·74, 95% CI: 1·34, 2·27; P = 0·000), current smoking status (RR = 1·23, 95% CI: 1·07, 1·41; P = 0·004), hypertension (RR = 1·62, 95% CI: 1·27, 2·06; P = 0·000), hyperlipidaemia (RR = 2·16, 95% CI: 1·79, 2·62; P = 0·000), diabetes mellitus (RR = 1·46, 95% CI: 1·27, 1·68; P = 0·000), obesity (RR = 1·58, 95% CI: 1·35,·1·85; P = 0·000), multiple fractures (RR = 2·14, 95% CI: 1·00, 4·60; P = 0·050), varicose veins (RR = 3·07, 95% CI: 1·12, 8·47; P = 0·030), prolonged operation time (weighted mean differences (WMD) = 1·22, 95% CI: 0·63, 1·81; P = 0·000) and prolonged bed rest time (WMD = 3·12, 95% CI: 2·96, 3·29; P = 0·000) were associated with an increased risk of developing VTE. The other variables, including age (<60 years), previous smoking, immobility, pregnancy, cancer, open fractures and combination with trauma were not identified as significant risk factors for VTE. Almost all the risk factors mentioned above are in line with the known risk factors for VTE following surgery for fractures below the hip. Thus, surgeons should pay close attention to patients with these medical conditions in order to reduce the incidence of VTE following surgical treatment of fractures below the hip.

Posterior dislocation of the hip with bilateral femoral fractures: An unusual combination.

Posterior hip dislocation with concomitant femoral fracture is very rare. Here, we report a rare case of a 43-year-old man who was injured in a car accident. The patient sustained right posterior hip dislocation with concomitant right acetabular transverse and posterior wall fracture, ipsilateral femoral shaft fracture, and contralateral proximal femoral fracture (AO type 31-A3). Closed reduction of the hip was attempted, but failed. The acetabular fracture and posterior hip dislocation were reduced and acetabular fracture was fixed using plates through the Kocher-Langenbeck approach. The ipsilateral femoral fracture was treated with closed reduction and intramedullary nailing. The contralateral femoral fracture was treated with closed reduction and Gamma 3 nailing. Postoperative X-rays revealed reduction of the fractures. The patient achieved bone union and recovered function of the hip 4 months after surgery.

Shockwaves induce osteogenic differentiation of human mesenchymal stem cells through ATP release and activation of P2X7 receptors.

Shockwave treatment promotes bone healing of nonunion fractures. In this study, we investigated whether this effect could be due to adenosine 5'-triphosphate (ATP) release-induced differentiation of human mesenchymal stem cells (hMSCs) into osteoprogenitor cells. Cultured bone marrow-derived hMSCs were subjected to shockwave treatment and ATP release was assessed. Osteogenic differentiation and mineralization of hMSCs were evaluated by examining alkaline phosphatase activity, osteocalcin production, and calcium nodule formation. Expression of P2X7 receptors and c-fos and c-jun mRNA was determined with real-time reverse transcription polymerase chain reaction and Western blotting. P2X7-siRNA, apyrase, P2 receptor antagonists, and p38 MAPK inhibitors were used to evaluate the roles of ATP release, P2X7 receptors, and p38 MAPK signaling in shockwave-induced osteogenic hMSCs differentiation. Shockwave treatment released significant amounts (≈ 7 µM) of ATP from hMSCs. Shockwaves and exogenous ATP induced c-fos and c-jun mRNA transcription, p38 MAPK activation, and hMSC differentiation. Removal of ATP with apyrase, targeting of P2X7 receptors with P2X7-siRNA or selective antagonists, or blockade of p38 MAPK with SB203580 prevented osteogenic differentiation of hMSCs. Our findings indicate that shockwaves release cellular ATP that activates P2X7 receptors and downstream signaling events that caused osteogenic differentiation of hMSCs. We conclude that shockwave therapy promotes bone healing through P2X7 receptor signaling, which contributes to hMSC differentiation.

Relationship between surgical time and postoperative complications in senile patients with hip fractures.

OBJECTIVE: To elucidate the relationship between surgical time and postoperative complications in senile patients with hip fractures, and try to find out other factors which are related to these complications. METHODS: Sixty-two patients, 28 males aged from 65 to 72 years with a mean age of 76.3 years and 34 females aged from 65 to 95 years with a mean age of 78.1 years, who had undergone orthopedic surgery because of hip fractures, were enrolled in a retrospective cohort study. The surgical time and pattern, the type of fracture, preoperative comorbidities, American Society of Anesthesiologists (ASA) score and the volume of blood transfusion during operation were obtained from these patients who were followed up by telephone calls for postoperative complications. All the patients were followed up at least for 1 year and were divided into subgroups according to their clinical characteristics and the results were analyzed by the Statistical Analysis System software. RESULTS: There was no significant difference in the morbidity of postoperative complications with the gender, age, surgical time and pattern, or ASA score. There was significant difference in the morbidity of postoperative complications related to preoperative comorbidities and the volume of blood transfusion. There was a significant causality between preoperative comorbidities and postoperative complications. The morbidity of postoperative complications was 1.651 times higher in patients with preoperative comorbidities than those without. CONCLUSIONS: There is no relationship between the surgical time and postoperative complications in senile patients who received surgery for hip fracture within 1 year. No correlation is found between the postoperative complications and gender, age, type of fracture, surgical pattern, ASA score and the volume of blood transfusion. Preoperative comorbidities are an independent predictor for postoperative complications.