Orientated-quantitative computed tomography study on individualized axial safety target area of femoral neck screw channel and establishment of a stable spatial coordinate system based on anterior cortex of femoral neck basilar.

BACKGROUND: Frequent in-out-in femoral neck screws were reported potential huge iatrogenic-injury risks, related to axial safe target area (ASTA) of femoral neck screws channel. However, orientated-quantitative ASTA based on stable coordinate system was unreported before. METHODS: Three-dimensional reconstruction was performed on computed tomography (CT) images of 139 intact normal hips, and the intersection area, defined as ASTA, was obtained by superimposing the axial CT images of each femoral neck. Taking anterior cortex of femoral neck basilar (AC-FNB) as landmark, a coordinate system was established to measure the anterior-posterior diameter (D-AP), the superior-inferior diameter (D-SI) and the oblique angle respectively. Each intersection was overlaid up to the axial CT images to determine the coronal location of the ASTA boundaries. RESULTS: Each ASTA presented an inclined rounded triangle with a flat anterior base coincided with AC-FNB. There were significant sex differences in D-SI (male: 33.6±2.3 vs. female: 29.4±1.9 mm) and D-AP (male: 25.3±2.1 vs. 21.9±1.9 mm), P <0.001. D-SI was found to be positively correlated with D-AP ( R2 =0.6). All fluoroscopic visible border isthmus completely matched the corresponding ASTA boundaries. The oblique angle was 5-53° (male: 28.1±10.3°, female: 27.1±8.2°) without significant difference between sexes. CONCLUSION: The intersection method was employed to conveniently acquire orientated-quantitative individualized ASTA. Under this coordinate system, x-ray data of screws could be converted to axial coordinates in CT ASTA, which could help surgeons design combined screws configuration preoperatively and evaluate quantitatively their axial position intraoperatively.

Angiopoietin-like 2 has auxo-action in atherosclerosis by promoting atherosclerotic calcification.

OBJECTIVE: To study the effects of angiopoietin-like 2 (Angptl2) on atherosclerotic calcification in aortic artery of ApoE-/- mice. METHODS: Twelve 6-week-old male mice were randomly divided into control group (n=6) and interventional group (n=6), the control group were fed with high fat diet and the interventional group were fed with high fat diet and at the eighth week interventional group mice were infused (intravenously) with purified recombinant Angptl-2 once a week for one month. All mice were sacrificed when the mice were 16 weeks old, blood was collected and plasma triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDLC) were measured, aortic sections were stained with hematoxylin and eosin (HE) or Von Kossa and were observed under microscope. Calcium content and alkaline phosphatase activity of aorta were measured to measure the degree of vascular calcification. The expressions of Runx2 protein and mRNA levels in aortic sections of mice were detected by immunohistochemistry, Western Blot and qRT-PCR respectively. RESULTS: The plasma TG, TC and LDLC level in interventional group was significantly higher than that in control group and the expression of Runx2 in aortic had the similar results. HE staining demonstrated significant thickening of the intima, with typical atherosclerotic plaque formation in interventional group mice, and Von Kossa staining showed spotty black clumps of aortic calcification under the fibrous cap plaque, while control group had atherosclerotic plaques without significant calcium deposits formation; The quantitative analysis showed that aortic vascular wall calcium and alkaline phosphatase activity were significantly higher in the intervention group than that of the control group (P<0.01). CONCLUSIONS: Angptl-2 could increase ApoE-/- mice plasma lipid level, it also facilitate the expression of Runx2, calcium content and ALP activity in aortic and then accelerate atherosclerotic calcification. Our experiments demonstrated that Angptl2 could accelerate atherosclerotic calcification. It reminded us that by controlling or decreasing the Anglt-2 level in plasma could help inhibit atherosclerotic calcification and then provides a new target to prevent coronary heart disease.

[Combination of volar buttress plate with external fixator for the distal radial fractures of type C3 caused by high-energy injuries].

OBJECTIVE: To preliminarily explore the effect of combination of volar buttress plate with external fixator for the distal radial fractures of type C3 caused by high-energy injuries. METHODS: From January 2001 to June 2007, 13 patients with distal radial fracture of type C3, 9 males and 4 females aged from 26 to 47 (average 37 years), were treated with volar buttress plate combined with external fixator plus the techniques of K-wires and bone grafting as necessary, whose effects were evaluated preliminarily through comparing the volar tilt, radial inclination, radial shortening and wrist function. RESULTS: Followed up from 7 to 29 months (average 18 months), the volar tilt, radial inclination, radial shortening and wrist function of all patients recovered remarkably. Nine patients achieved excellent and 4 good according to Sarmiento score (modified by Stewart) in the radiological manifestation, while 5 patients displayed excellent, 6 good, and 2 fair according to Gartland-Werley functional assessment system. CONCLUSION: 1) Volar buttress plate could support the valor cortex in order to prevent comminuted fragment from displacing and maintain volar tilt and to provide the volar fulcrum for external fixator. 2) External fixator, with the assistance of volar fulcrum, could maintain the volar tilt and the height of distal radius and help unload the fossa. 3) Supplemental K-wires fixation and the bone graft may assist fracture stable.