Research progress in application of neutrophil to lymphocyte ratio in bone and joint injury and related complications / 中华创伤骨科杂志

The neutrophil-to-lymphocyte ratio (NLR), the ratio of inflammatory cell counts in the blood, reflects the changes of neutrophils and lymphocytes in the inflammatory system in the peripheral blood. More and more scholars have found that NLR increases in patients with bone and joint injury, which can be used to predict postoperative mortality, infection, deep vein thrombosis, pain and other complications. This article is intended to review the application of NLR in bone and joint injury and related complications, providing reference for clinical application of NLR.

Biomechanical comparison of triangle supporting fixation system and Gamma nail fixation in the treatment of intertrochanteric fractures of the femur: finite element analysis / 中华骨科杂志

Objective:To compare the biomechanical properties of triangular supporting fixation and Gamma nail fixation for intertrochanteric fractures of the femur.Methods:The femoral CT imaging data provided by a healthy adult male volunteer aged 40 years, height 172 cm, and weight 75 kg were used to reconstruct the femur model using Mimics 21.0 software and Geomagics 2013 software. Evans type I intertrochanteric fracture models were established using UG12.0 software, and Gamma nail and triangular supporting intramedullary nail models were reconstructed to simulate intertrochanteric fracture internal fixation, respectively. In Abaqus software, two internal fixation models of Gamma nail and triangular supporting intramedullary nail in standing state are simulated, and the stress peaks of the main nail, fixation screw and bone substance were collected, also the stress peak of supporting screw of the triangular supporting intramedullary nail is obtained. Additionally, the maximum displacement of the fracture model fixed by Gamma nail and triangular supporting intramedullary nail is measured.Results:Under the load of 1 200 N, the peak stress of the two fracture internal fixation models was located in the main nail, in which the peak stress of the triangular supporting intramedullary nail was 233.73 MPa, which was 11.9% lower than that of the Gamma nail (265.21 MPa); the peak stress of the fixation screw was located in the contact area between the pressure screw and the main nail, which was 23.2% lower in triangular supporting intramedullary nail than that of the Gamma nail (138.86 MPa vs. 180.75 MPa); the peak stress of the bone model was located in the medial cortex of the femur, which was 61.67 MPa and 32.38 MPa, respectively, 47.5% lower in the triangular supporting intramedullary nail than that of the Gamma nail; the peak stress of the supporting screw in the triangular supporting intramedullary nail was 92.04 MPa. The maximum displacement of the fracture model fixed with triangular supporting intramedullary nail was 17.34 mm, which was 10.5% less than the maximum displacement of the fracture model fixed with Gamma nail (19.37 mm). Conclusion:Compared with Gamma nail, triangular supporting intramedullary nail fixation can significantly improve the stability of intertrochanteric fractures and stress distribution as well as reduce stress peak and stress concentration area, which is helpful to improve the efficacy of intertrochanteric fractures.

Triangular supporting fixation: an innovative surgical approach for intertrochanteric fractures of the femur--Evidence from a biomechanical study / 中华创伤骨科杂志

Objective:To compare the biomechanical properties between triangular supporting fixation and conventional dynamic hip screw (DHS) fixation in the treatment of femoral intertrochanteric fractures.Methods:Eight pairs of 16 femoral specimens with an average death age of 51.9 years were used in this study. After thawing, they were randomly divided into an experimental group ( n=8) and a control group ( n=8) according to the left or right laterality. They were made models of femoral intertrochanteric fracture of AO 31-A1 type with strain gauges pasted. The experimental group was subjected to fixation with double triangu-lar supporting and the control group conventional DHS fixation to achieve anatomical reduction. The specimens were then mounted onto a biomechanical testing machine and subjected to loading till 400 N at a rate of 10 N/s. The values of overall deformation of the specimens and strain at 16 selected sites were recorded and compared between the 2 model groups. Results:Under the load of 400 N, the overall deformation was (0.31±0.13) mm for the experimental group and (0.49±0.21) mm for the control group, showing a significant difference ( t=-2.456, P=0.023). The strain values in front of femoral neck, upon front fracture line, at inferior-lateral, inferior-median and inferior-interior sites of front fracture line, at the root of anterior fixation screw, below medial femoral neck fracture line, behind femoral neck, at superior-lateral, superior-median and superior-interior sites of posterior fracture line, below posterior fracture line, at superior and inferior roots of posterior fixation screw, at points parallel to the fixation screw in front of and behind femoral shaft were, respectively, -244.90, 13.16, -71.77, -124.38, -366.89,121.62, -10.94, -166.00, -54.93, -367.38, -608.93, -69.09, 326.50, 133.14, 52.97, and -185.82 in the experimental group and -24.62, -40.39, -36.99, -120.97, -486.38, 99.20, 35.36, -205.67, -74.30, -566.01, -1, 085.40, -77.41, 334.34, 114.08, 38.50, and -235.74 in the control group. Internal fixation failure occurred in one specimen in the control group after 1,759 cycles of loading but in none in the experimental group. Conclusion:For femoral intertrochanteric fractures, double triangular supporting fixation may result in less overall deformation and is more consistent with the normal biomechanical conduction of the femur than conventional DHS fixation.

A study on injury mechanism of tibial plateau Hoffa fracture / 中华创伤骨科杂志

Objective:To understand and verify the biomechanical mechanism of tibial plateau Hoffa (coronal) fracture by simulating high-altitude falls and traffic injuries using knee joint specimens.Methods:Ten specimens of lower limb knee joint were used. They were from 6 males and 4 females, with an average age of 57.4 years (from 42 to 65 years). They were divided into 2 equal groups: one subjected to simulation of high-altitude falls (fall group) and the other to simulation of traffic injury (traffic injury group). After injury simulation, standard orthographic and lateral X-ray examinations and CT scans were performed of the knee joints in the extended position to observe whether there was a fracture, where the fracture occurred, and how the fracture line went.Results:A tibial plateau coronal fracture was successfully simulated in 6 cases, but not in the other 4 cases. The failure was attributed to femoral fractures and other types of tibial plateau fracture. In the 3 successful fractures simulated by high-altitude fall, the fracture line was located all on the posterior medial side, involving the posterior 1/3, 2/5, and 1/2 of the tibial plateau, respectively. The fracture line and the coronal plane formed angles of 21°, 19° and 12°, respectively. The fracture was not shown on X-ray film in one case which was a posterior medial fracture on CT. In the other 3 successful fractures simulated by traffic injury, the fracture line involved 1/6, 1/4 and 1/3 of the posterior tibial plateau, respectively. The angles between the fracture line and the coronal plane were 47°, 56° and 63°, respectively. One case showed no obvious fracture signs on the X-ray but a coronal fracture on CT.Conclusions:This study has confirmed for the first time that both high-altitude falls and traffic injuries can cause coronal fractures of the tibial plateau which vary significantly in the extent of involvement and morphology. X-rays are not sufficient to fully diagnose this type of fractures, suggesting that patients with a clear history of knee flexion or axial violence injury should be routinely scanned by CT to reduce risks of missed diagnosis and insufficient treatment.

Knocking-out extra domain A alternative splice fragment of fibronectin using a clustered regularly interspaced short palindromic repeats/associated proteins 9 system / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of the fibronectin extra domain A on the aggressiveness of salivary adenoid cystic carcinoma (SACC) cells, via the clustered regularly interspaced short palindromic repeats (CRISPR)/ associated proteins (Cas) system.</p><p><b>METHODS</b>One sgRNA was designed to target the upstream of the genome sequences of extra domain A(EDA) exon and the downstream. Then the sgRNA was linked into plasmid PX-330 and transfected into SACC-83 cells. PCR and DNA sequence were used to testify the knockout cells, and the monoclones of EDA absent SACC cells were selected (A+C-2, A+C-6, B+C-10). CCK-8 cell proliferation and invasion was then tested in control group and the experimental group.</p><p><b>RESULTS</b>The sgRNA was successfully linked into PX-330 plasmid. Part of adenoid cystic carcinoma cells' SACC-83 genomic EDA exon was knocked out, and the knockdown efficiency was above 70%, but the total amount of fibronectin did not change significantly. Three monoclones of EDA absent SACC- 83 cells were successfully selected with diminished migration and proliferation.</p><p><b>CONCLUSIONS</b>The CRISPR/Cas9 system was a simplified system with relatively high knockout efficiency and EDA knockout could inhibiting SACC cell's mobility and invasiveness.</p>

Expression of Vascular Endothelial Growth Factor and nm23 Proteins and Microvessel Density in Hepatocellular Carcinoma and Their Relation With Metastasis / 中国医师杂志

Objective To investigate expressions of vascular endothelial growth factor (VEGF) and nm23 proteins and microvessel density in HCC,simultaneously,their relation with metastasis was also studied.Methods The expression of VEGF and nm23 and CD34 protein in 56 HCCs were detected by immunohistochemical technique.Results Of 56 HCCs, the intensity of VEGF expression in HCCs with metastasis was significantly higher than that in HCCs without metastasis (P