A novel fluffy PLGA/HA composite scaffold for bone defect repair.

Treatment of bone defects remains crucial challenge for successful bone healing, which arouses great interests in designing and fabricating ideal biomaterials. In this regard, the present study focuses on developing a novel fluffy scaffold of poly Lactide-co-glycolide (PLGA) composites with hydroxyapatite (HA) scaffold used in bone defect repair in rabbits. This fluffy PLGA/HA composite scaffold was fabricated by using multi-electro-spinning combined with biomineralization technology. In vitro analysis of human bone marrow mesenchymal stem cells (BMSCs) seeded onto fluffy PLGA/HA composite scaffold showed their ability to adhere, proliferate and cell viability. Transplant of fluffy PLGA/HA composite scaffold in a rabbit model showed a significant increase in mineralized tissue production compared to conventional and fluffy PLGA/HA composite scaffold. These findings are promising for fluffy PLGA/HA composite scaffolds used in bone defects.

Analysis of limb swelling and pain caused by a tourniquet after total knee arthroplasty / 医学研究生学报

The advantages of the tourniquet in total knee arthroplasty are favored by surgeons. However, tourniquets can aggravate the swelling and pain of postoperative limbs，which is not good for early functional exercise. Researchers conducted many related studies which only stayed in clinical manifestations and did not clarify the causes and mechanisms of swelling and pain，So there are no positive effect on the prevention and treatment of swelling and pain. Tourniquets can cause ischemia, hypoxia and reperfusion injury in limbs, leading to local tissue inflammatory reactions, vascular injury, microcirculatory disorders, abnormal coagulation, deep venous thrombosis, lymphatic drainage disorders, joint cavity occult hemorrhage, effusion and the damage of distant organs, which eventually exacerbated the degree of swelling and pain of the limb. Therefore, the above factors are reviewed in this article.

Comparison of the outcome of intra-articular injection of cocktail and betamethasone injection after rotator cuff repair / 医学研究生学报

Objective Shoulder surgery is associated with moderate to severe pain, but there is a lack of consensus on the best analgesic method. This study was conducted to evaluate whether intra-articular injections of cocktails (betamethasone hydrochloride combined with ropivacaine) achieved better clinical effects than betamethasone hydrochloride alone after arthroscopic rotator cuff repair.Methods Eighty-six patients with rotator cuff repair under arthroscopy in our hospital from March 2017 to October 2017 were selected and divided into experiment group( ropivacaine75 mg+(betamethasone hydrochloride 2 mL) and control group((betamethasone hydrochloride 4 mL), each group 43. Visual acuity score(VAS) and the satisfaction of patients were evaluated before operation and at 4, 8, 12, 24, 48 h postoperatively.Results There was no significant difference in VAS before operation and 48 h after operation between experimental group and control group (P>0.05). But at 4, 8, 12 and 24 h after operation the VAS in experimental group is lower than that in control group(P0.05).Conclusion Cocktail (betamethasone combined with ropivacaine) intra-articular injection can significantly reduce the postoperative earlier pain within 24 hours and can improve the satisfaction of patients.

The application of serum endotoxin detection in the diagnosis of artificial prosthetic joint loosening / 医学研究生学报

Objective The dynamic detection of endotoxin is of great significance for the early diagnosis and treatment of prosthesis loosening after joint replacement. This study aimed to explore and analyze the clinical significance and efficacy of endotoxin detection in prosthetic joint loosening after joint replacement.Methods Fifty-eight patients who underwent arthroplasty in the department of orthopedics in Nanjing General Hospital from January 2015 to June 2016 were selected for prospective study. The patients were divided into the infection loosening group (patients with infectious loosening after arthroplasty, n=15), the aseptic loosening group (patients with aseptic loosening of after arthroplasty, n=23) and the control group (patients were normal after arthroplasty, n=20) according to the postoperative complications. Endotoxin was detected with MB-80 microbial dynamic rapid detection system. We compared the endotoxin level and the ROC curve was made to acquire the sensitivity and specificity under the different cut-off values. Eventually find the best diagnostic threshold.Results The levels of endotoxin in the infection loosening group and the aseptic loosening group \[(0.56±0.11, 0.49±0.08) ng/mL\] were significantly higher than that in the control group \[(0.24±0.06) ng/mL\]. The difference was statistically significant (P0.05). ROC curve analysis showed that when the serum endotoxin concentration was 0.36 ng/mL, the Youden index was the highest, which could be the best cut-off value for diagnosis. It had the best accuracy to judge the prosthesis loosening with a sensitivity of 66.7% and specificity of 88.2%.Conclusion The endotoxin can be a good indicator for early diagnosis of prosthesis looseness. It is helpful to the diagnosis of the prosthesis loosening after arthroplasty.

The relationship between different tourniquet pressures in total knee arthroplasty and the pain and swelling of the affected limb after surgery / 医学研究生学报

Objective The use of tourniquets in total knee arthroplasty has been controversial. Many studies have focused only on the different time courses and neglected the effects of pressures. Currently,there is no study explaining the mechanism of tourniquet-induced injury. The aim of this study was to explore the effects of different tourniquet pressures on pain and swelling after total knee arthroplasty and to explore the mechanism of injury. Methods Ninety-six patients who underwent total knee arthroplasty at Nanjing General Hospital from June 2017 to December 2017 were randomly as-signed to 240 mmHg group (low pressure),270 mmHg group (medi- um pressure),and 300 mmHg group (high pressure). The patient's pain and thigh circumference were measured before and 1-2 days after surgery. Blood samples were taken before and 3,8,and 24 hours after surgery. Superoxide dismutase 1 (SOD1),prostaglandin E2 (PGE2) and myoglobin were detected,analysed and compared. Results In the perspective of the pain and swelling of affected limb after surgery,the 300 mmHg group (73.24±10.51) was significantly different from the 240 mmHg group (58.18±9.66) and the 270mmHg group (63.06±10.06). In the perspective of the SOD1 level in serum,the 300mmHg group (97.77±13.82) was significant-ly different from the 240mmHg group (63.72±15.02) and the 270 mmHg group (70.58±5.85) at 3h after surgery,and then the diver-gence was gradually decreased. In the perspective of the PGE2 level in serum,the 300 mmHg group (478.05±35.80) was significantly different from the 240mmHg group (334.42±33.12) and the 270mmHg group (391.85±19.41) at 3h after surgery,and the divergence was started to decrease after 8 h. In the perspective of the myoglobin level in serum,the 300 mmHg group (30.43±9.79) was also sig-nificantly different from the 240 mmHg group (17.58±1.93) and the 270 mmHg group (22.28±4.21) at 8 h after operation,the diver-gence was started to decrease after 24 h. which began to decrease after 24 h. Correlation analysis showed that there was a significant cor-relation between pain (correlation coefficient 0.518,P<0.001),swelling (correlation coefficient 0.345,P<0.05) and stress after sur-gery. Conclusion The pain and swelling of the affected limb is positively correlated with the pressure of the tourniquet during the operation. Muscle necrosis is the main mechanism of the injury. Oxidative stress occurs in the ischemic phase and inflammation occurs in the reperfusion phase.