A Comparative Analysis of Between Percutaneous Cannulated Screw Fixation and Traditional Plate Internal Fixation in Treatment of Sanders II and III Calcaneal Fractures.

The objective of this study is to compare the clinical efficacy of percutaneous cannulated screw fixation and traditional plate internal fixation in the treatment of Sanders II and III calcaneal fractures. The records of 64 patients were retrospectively analyzed. Thirty-three cases were fixed by percutaneous cannulated screws. Thirty-one cases were fixed with traditional steel plates. The preoperative preparation time of the screw group and plate group was 3 ± 1.7 days and 4.6 ± 2.1 days. The surgery time was 118.9 ± 43.8 minutes and 146.9 ± 47.6 minutes. The length of hospitalization was 8.7 ± 3.9 days and 17.0 ± 7.9 days. Intraoperative blood loss was 38.2 ± 27.7 mL and 67.1 ± 58.8 mL. The postoperative drainage volume of the plate group was 85.1 ± 53.7 mL, and no wound drainage was needed in the screw group after surgery. Postoperative wound complications occurred in 2 cases of the screw group and 8 cases of the plate group. The recovery effects of Gissane angle and Bohler angle are similar in the 2 groups. The excellent and good rate of the American Orthopaedic Foot and Ankle Society ankle-hindfoot Scale in the screw group was 96.8% at 12 months after surgery, whereas the rate was 93.5% in the plate group. Compared with the traditional plate internal fixation, the percutaneous cannulated screw group achieved a similar excellent and good rate of clinical treatment. It has the advantages of less trauma, less bleeding, low incidence of complications, short preoperative preparation, and hospitalization time.

MicroRNA-664a-5p promotes osteogenic differentiation of human bone marrow-derived mesenchymal stem cells by directly downregulating HMGA2.

Osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (BMSCs) has been regarded as a central issue in fracture healing. MicroRNAs (miRNAs, miRs) participate in diverse physiological processes such as osteoblastic differentiation of BMSCs. In this study, we found that miR-664a-5p was upregulated during osteogenic differentiation of human BMSCs, and this upregulation positively correlated with the expression of osteogenic genes Runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteocalcin (OCN). Overexpression of miR-664a-5p promoted the osteogenic differentiation of BMSCs, whereas a knockdown of miR-664a-5p suppressed it. Additionally, high-mobility group A2 (HMGA2) mRNA was identified as a direct target of miR-664a-5p that mediates the function of this miRNA. Overexpression of HMGA2 obviously attenuated miR-664a-5p-induced osteogenic differentiation of BMSCs. Thus, the newly identified miR-664a-5p-HMGA2 pathway expands our understanding of the mechanisms underlying the osteogenic differentiation of human BMSCs, may provide deeper insights into the regulation of this differentiation, and can point to new effective methods for treating osteoporosis.

TMEM18 inhibits osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells by inactivating ß-catenin.

Transmembrane protein 18 (Tmem18) is an obesity-associated gene essential for adipogenesis; however, its function in the osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) is still unclear. In this study, we found that Tmem18 was significantly downregulated in rat BMSCs after osteogenic induction. TMEM18 overexpression remarkably downregulated osteo-specific genes including alkaline phosphatase (Alp), Runt-related transcription factor 2 (Runx2), osteocalcin (Ocn), and osteopontin (Opn), and reduced the number of mineral deposits and ALP activity in vitro, whereas knockdown of Tmem18 yielded the opposite results. In vivo assays also indicated that TMEM18 knockdown BMSCs have an increased bone formation potential in a rat model of calvarial defects. Analyses of the mechanism suggested that TMEM18 overexpression decreased ß-catenin expression, whereas the TMEM18 knockdown enhanced ß-catenin expression and promoted its nuclear translocation. The positive effects on osteogenic differentiation of rat BMSCs owing to the TMEM18 knockdown were attenuated by ß-catenin downregulation. Taken together, these results indicate that TMEM18 plays an inhibitory role in osteogenic differentiation of BMSCs via inactivation of ß-catenin.

[Limited open reduction and double plates internal fixation for treatment of Vancouver type B1 periprosthetic femoral fracture after hip arthroplasty].

OBJECTIVE: To evaluate the effectiveness of limited open reduction and double plates internal fixation in the treatment of Vancouver type B1 periprosthetic femoral fracture after hip arthroplasty. METHODS: A retrospective analysis was made on the clinical data of 12 patients with Vancouver type B1 periprosthetic femoral fracture after hip arthroplasty between May 2007 and October 2012, who underwent limited open reduction and double plates internal fixation. Of 12 patients, 4 were male and 8 were female, aged 76-85 years (mean, 81.6 years); the left side was involved in 5 patients and the right side in 7 patients. The cement prosthesis was used in 3 cases and cementless prosthesis in 9 cases; double acting head of hip arthroplasty was performed in 4 cases and total hip arthroplasty in 8 cases. The median time from first hip arthroplasty to re-fracture was 13 months (range, 5 months-5 years). The causes of injury were traffic accident in 2 cases and falling in 10 cases. Combined fractures included contralateral tibial and fibular fractures and ipsilateral distal humeral fracture (1 case), ipsilateral proximal humeral fracture (2 cases), ipsilateral distal radial fracture (1 case), and rib fracture (1 case). The time from injury to operation was 5.6 days on average (range, 3-10 days). RESULTS: The incisions all healed by first intention, and no infection or deep venous thrombosis of lower extremity occurred. Twelve cases were followed up 6-24 months (mean, 13.3 months). One female patient died of acute myocardial infarction at 16 months after operation. All the fractures were healed, with X-ray healing time of 12.5 weeks on average (range, 10-16 weeks). The time of full weight bearing was 13 weeks on average (range, 10-18 weeks). Ten cases could walk freely after operation, and 2 cases could walk by the aid of walking aid appliance. At last follow-up, the Harris score of hip function was 87.3 on average (range, 75-93). CONCLUSION: The method of limited open reduction and double plates internal fixation for Vancouver type B1 periprosthetic femoral fracture after hip arthroplasty is effective in maintaining stability, protecting blood supply, promoting fracture healing, and doing functional exercise early. The long-term effectiveness needs further observation.