BACKGROUND: Minimally invasive percutaneous pedicle screw fixation possesses the advantages of less blood loss, less muscle and soft tissue dissection, and rapid recovery; however, accuracy of the screw positioning is the key to be successful.OBJECTIVE: To explore the application value of self-designed spinal localizer in the screw positioning for minimally invasive percutaneous pedicle screw fixation.METHODS: 428 patients with thoracolumber disorders were subjected to minimally invasive percutaneous pedicle screw fixation at the First Affiliated Hospital of University of South China, from March 2009 to March 2015, and randomly underwent the preoperative screw positioning by self-designed spinal localizer or one of traditional localizing methods (iliac crest, ribs, symptomatic vertebral appearance, skin marker, Kirscher wire, puncture needle localizations). The location accuracy, positioning time and radiographic times were compared among methods.RESULTS AND CONCLUSION: (1) Compared with the traditional localization methods, the self-designed spinal localizer was superior in accurate rate (P < 0.05), cost less positioning time (P < 0.05) and received less radiation (P < 0.05). (2) To conclude, the self-designed localizer exhibits a certain application value, which is an ideal method in preoperative localization for minimally invasive percutaneous pedicle screw fixation.

BACKGROUND: T-type or linear type external fixator is applied in transcervical fracture in the elderly. Because its fixing force is weak, so it is difficult to avoid the aggravation of complication due to long term lay up in severe osteoporosis. Based on this reason,percutaneous penetrating arch tri-claw external fixator is designed to treat elderly transcervical fracture with strong fixing force for the realization of early restoration to the active status before injury to reduce complication.OBJECTIVE:To design pereutaneous penetrating arch tri-claw external fixator for the treatment of elderly transcervical fracture for the investigation of its feasibility.DESIGN: A self-controlled study by employing patients as subjects.SETTING: Department of orthopedic surgery of the first affiliated hospital of a universityPARTICIPANTS: Thirty-one cases of elderly transcervical fracture including 18 males and 13 females aged between 71 and 86 years old with an average age of 79 years were admitted by the Department of Orthopedics of the First Affiliated Hospital of Nanhua University between December 2002 and June 2004.METHODS: Percutaneous penetrating arch tri-claw external fixator was applied in the treatment of 31 cases with elderly transcervical fracture for the observation of its clinical effects, and the force-bearing situation and stability of the external fixator during application were analyzed by theoretical mechanics.MAIN OUTCOME MEASURES: ① The functional effects of percutaneous penetrating arch tri-claw external fixator applied in the therapy of transcervical fracture(sub-femoral head type,transcervical type and femoral basilar type); 2② The force-bearing situation and the stability of the fixing point on the fixator; ③ The restoration of activity in hip joint and fracture union time RESULTS: ① Patients could sit and stand immediately after the applicationof the fixator, and its fixing reinforce was analyzed by theoretic mechanics during standing(the force on upper fixing point A, B or C was 1/22, 1/2 or 1/2 of the lower fixing point) . The unidirectional flexion and extension activity of the hip joint overcame hip-inversion and rotational disposition at the distal end of the fracture. The hip-joint axial compression board caused compact embedment and insertion of the fracture end and vertical crush to simulate fracture union by stability and compressive strain. ② The stability of percutaneous penetrating arch tri-claw external fixator: No disposition was found during the application except rotational disposition during activity in sub-femoral head type fracture. The fixation was stable, the operative trauma was less,and the operation was simple with good accommodation. No complication was found due to long-term lay up and no re-disposition due to the loosening of the external fixator was found. ③ The hip-joint flexion-extension function was restored within 7 days averagely and fracture healing time was about 2 to 3 months, average of 2.4 months.CONCLUSION: No re-injury is found dter the application of percutaneous penetrating arch tri-claw external fixator, which has small force bearing at upper fixing point with strong stability. There is strain stimulation on the cross section of the fracture to promote fracture healing. The articular function status before injury could be restored at early stage.

Objective To investigate the effect of urinary training on urination control in infants using nappies after birth.Methods Stratified sampling method was used to investigate the daytime urination control and the using of diapers by children in kindergartens of 6 prefecture-level cities in Henan Province,China.The survey was conducted among parents of healthy children.Results In a total of 12 250 questionnaires,11 697 had response,and 10 562 valid questionnaires were collected,and the effective recovery rate was 86.22％.After the birth of infants,the age of toilet training was divided into 6 groups (0-＜ 3 months old group,3-＜ 6 months old group,6-＜ 12 months old group,12-＜ 18 months old group,18-＜ 24 months old group and no toilet training group).Results showed that toilet training within 12 months leads to higher urinary control rate compared with toilet training after 12 months and no toilet training till the age of 2 years old,70.56％ (4 831/6 847 cases) in contrast with 59.02％ (1 545/2 618 cases) and 42.48％ (466/1 097 cases),and the differences were statistically significant (x2 =114.76,335.48,all P ＜ 0.000 1).Within 12 months,there was no statistical difference in the urinary control rate between subgroups at 2 years of age(all P ＞0.05).After 12 months,the urination control rate decreased with the start time delayed till 2 years of age,and the urinary control rate at the age of 2 years old n different groups was 59.97％ (1 314/2 191 cases) and 54.10％ (231/427 cases) respectively.The results of other ages(0.5,1.0,1.5 years old) were similar to those of 2 years old.There was no difference between the groups of different genders (all P ＞ 0.05).Conclusions The use of diapers in infants before the age of 1 year to start urinary training is conducive to the development of urinary control in infants.

Objective:To establish a hypergravity loading model with a high-acceleration centrifugal loading device and to investigate the effects of different hypergravity loading and icariin on osteoblast adhesion and cytoskeleton.Methods:MC3T3-E1 cells were seeded in the dishes of cell culture at a density of 2×10 5/cm 2. And the experiment was divided into 6 groups: control group (without icariin and loading); simple administration group (only icariin); 10 G loading group (only loading); 10 G administration group (with icariin and loading); 40 G loading group (only loading); 40 G administration group (with icariin and loading). The experimental loading group was loaded with MC3T3-E1 cells using a high-acceleration centrifugal loader. And continuous loading for 3 d, 30 min per d. The control group and the simple administration group were exposed to normal gravity, and the remaining conditions were not different from the experimental group. Icariin was used at a concentration of 10 -7 mol/L in all administration groups, and the experiments were carried out according to the method of preventive administration. At the same time, the related molecular biological techniques such as alizarin red staining, alkaline phosphatase (ALP) activity measurement, CCK-8 cell proliferation experiment, cytoskeleton phalloidin staining, qPCR and Western Blot were used to detect the effects of icariin on osteoblasts adhesion protein integrin α5 and integrin β1 and cytoskeleton protein F-actin under hypergravity extreme mechanical environment. Results:All models were successfully prepared. The alizarin red staining: The icariin could significantly promote the formation of osteoblastic calcified nodules. And the 10 G loading could also promote the mineralization of osteoblasts and increase the number of mineralized nodules, while the mineralization and the number of mineralized nodules of osteoblasts are significantly reduced in 40 G loading. ALP activity test: The OD values of simple administration group, 10 G loading group and 40 G loading group were 0.246, 0.331 and 0.163, respectively. Compared with 0.207 in the control group, the differences were statistically significant ( P<0.05). The 10 G administration group and the 40 G administration group were 0.373 and 0.180, and the differences were statistically significant ( P<0.05). The results of CCK-8 proliferation experiments: The OD value of simple administration group were 0.650, which was statistically significant compared with 0.551 of control group ( P=0.031). The 10 G loading group and 40 G loading group were 1.193 and 0.245, and their differences with the control group were both statistically significant ( P<0.05). The OD value of 10G administration group and the 40 G administration group were 1.300 and 0.310, which were significantly different from the respective loading groups ( P<0.05). Phalloidin staining: 10 G loading significantly increased the number of cells, but the changes in cells morphology and skeleton were not obvious. 40 G loading significantly inhibited the increase of the number of cells, meanwhile, made the pseudopods of cells more shorter and even disappeared. 40 G loading made the seriously damage of the cytoskeleton and even cause the cells to death. Icariin had no effect on the cells morphology, but it did has a certain repair effect after the cells loading. The results of qPCR and Western Blot experiments all confirmed that the expressions of integrin α5, integrin β1 and F-actin were up-regulated after icariin treatment. 10 G loading could promote the expression of integrin α5, integrin β1 and F-actin, and 40 G loading significantly inhibited the expression of the mRNA and proteins. Conclusion:Both 10 G condition and icariin can promote the development, cell adhesion and the cytoskeleton's stability of osteoblasts, while 40 G has a significant inhibitory effect.

Objective To construct a two-dimensional (2D) composite membrane and a three-dimensional (3D) biomimetic scaffold by silk fibroin (SF), type I collagen (Col-I) and hydroxyapatite (HA) blends in vitro, so as to study its physicochemical properties, as well as biocompatibility and explore the feasibility of its application in tissue engineering scaffold materials. Methods 2D composite membranes and 3D scaffolds were prepared by blending SF/Col-I/HA at the bottom of cell culture chamber and low temperature 3D printing combined with vacuum freeze drying. The biocompatibility was evaluated by mechanical property testing, scanning electron microscope and Micro-CT to examine the physicochemical properties of the material, and cell proliferation was detected to evaluate its biocompatibility. Results Stable 2D composite membrane and 3D porous structural scaffolds were obtained by blending and low temperature 3D printing. The mechanical properties were consistent. The pore size, water absorption, porosity and elastic modulus were all in accordance with the requirements of constructing tissue engineering bone. The scaffold was a grid-like white cube with good internal pore connectivity; HA was evenly distributed in the composite membrane, and the cells were attached to the composite membrane in a flat shape; the cells were distributed around pore walls of the scaffold. The shape of the shuttle was fusiform, and the growth and proliferation were good. Conclusions The composite membrane and 3D scaffold prepared by SF/Col-I/HA blending system had better pore connectivity and pore structure, which was beneficial to cell and tissue growth and nutrient transport. Its physicochemical properties and biocompatibility could meet the requirements of bone tissue engineering biomaterials.

Objective To establish the model of goat intervertebral disc degeneration （IDD） induced by controllable axial compressive stress and evaluate its imaging and pathological characteristics. Methods Twenty goats were randomly divided into 4 groups (control group, 4-week pressure group, 8-week pressure group, 12-week pressure group, n=5, 40 N pressure). Disc height index (DHI) was used to evaluate the change of intervertebral disc height by X-ray, Pfirrmann classification method was used to observe the degree of intervertebral disc degeneration by magnetic resonance imaging (MRI), and histopathological observation and evaluation for intervertebral disc were conducted by HE staining and immunohistochemistry. Results DHI in control group showed no significant changes with the extension of pressure time, while DHI in the experimental group gradually decreased. There was no significant change in Pfirrmann classification in control group. In experimental group, with the extension of time, the higher the degeneration aggravated with the Pfirrmann classification increasing. In experimental group, HE staining showed that the disc nucleus pulposus decreased in volume and nucleus pulposus cells, which were gradually replaced by fibrous tissues. Immunohistochemical staining showed that type I collagen in the nucleus pulposus gradually increased, type Ⅱ collagen gradually decreased, and intervertebral disc degeneration occurred. Conclusions A certain axial compressive stress can lead to degeneration of goat lumbar intervertebral disc, and the degree of degeneration is gradually increased with the extension of time.