Advances on research of physical environment affecting stem cell differentiation in ligament tissue engineering / 中国骨伤

Ligament tissue engineering is currently a novel approach to the treatment of ligament injury, which can replace the deficiency of autografts. Ligament tissue engineering consists of four basic elements:seed cells, nanoscaffolds, growth factors, and mechanical stimulation. At present, the main problem in ligament tissue engineering is how to control seed cells to ligament cells more controllly. The study found that each physical property of the natural bio ligament and mechanical stimulation (uniaxial stretching) plays an important role in the differentiation of stem cells into ligament cells. Therefore, the design of nanofiber scaffolds must consider the elastic modulus of the material and the material. Structure(material arrangement, porosity and diameter, etc.), elastic modulus and material structure in different ranges will guide cells to differentiate into different lineages. Considering that the ligament is the main force-bearing tissue of the human body, mechanical stimulation is also essential for stem cell differentiation, especially uniaxial stretching, which best meets the stress of the ligament in the body. A large number of studies have found the frequency and amplitude of stretching. And time will also lead the cells to differentiate in different directions. RhoA/ROCK plays a regulatory role in cytoskeletal remodeling and cell differentiation. It is also found that RhoA/ROCK protein participates in the process of nanofiber arrangement and uniaxial stretching to guide stem cells to differentiate into ligament cells, specifically how to influence stem cell differentiation. It is not clear at present that understanding the effects of physical properties on stem cell differentiation and understanding the mechanism of action of RhoA/ROCK protein will provide a new theoretical basis for further optimization of ligament tissue engineering.

Case-control study on the modified ilioinguinal incision of anterior approach for the treatment of pelvic and acetabular fractures / 中国骨伤

<p><b>OBJECTIVE</b>To study modified ilioinguinal approach through the retrospective analysis on the surgical treatment of 63 patients with pelvic and acetabular fractures through anterior approach.</p><p><b>METHODS</b>From January 2006 to January 2013, 63 patients with pelvic and acetabular fractures were treated with the ilioinguinal anterior approach, including 45 males and 18 females, ranging in age from 12 to 68 years old, with an average of (37.71 +/- 13.41) years old. All the patients were divided into two groups: standard ilioinguinal anterior approach group (group A) and modified ilioinguinal anterior approach group(group B). In group A, there were 26 males and 11 females, with an average age of (38.49 +/- 13.64) years old. In group B, there were 19 males and 7 females, with an average age of (36.62 +/- 13.29) years old. Intraoperative and postoperative indicators in group A and B were observed and compared, including operation incision exposure time (from skin incision to complete the ilioinguinal in front of three "windows"), the blood loss, incision close time and treatment effect of Majeed function score.</p><p><b>RESULTS</b>Compared to group A, the incision exposure time of patients in group B was shorter, the blood loss (bleeding during exposure process) was less, and the close incision time was shorter, but the treatment effect of Majeed function score had no significant differences between two groups. All the patients were followed up, and the during ranged from 3 to 36 months, with an average of (18.6 +/- 9.2) months. According to Matta standard assessment reduction of pelvic and acetabular fracture, there were 28 patients got an excellent result, 8 good, and 1 fair in the group A; and 20 patients got an excellent result, 5 good, and 1 fair in the group B. According to Majeed function score for hip function, 20 patients got a satisfactory result, 12 good,4 fair and 1 poor in group A, and the mean score was 82.51 +/- 9.72; and 13 patients got an satisfactory result, 10 good, 3 fair and 0 poor in group B, and the mean score was 80.54 +/- 10.79.</p><p><b>CONCLUSION</b>The modified approach has several advantages as follows: providing a good surgical exposure; preventing from the injury of femoral nerve, femoral artery and vein under the inguinal ligament; not needing to open the inguinal canal, which can avoid the occurrence of inguinal hernia, reduce operation prodedures and shorten operation time.</p>