Objective To analyze the evolution of acetabular morphology changes of different Crowe types among adults with developmental dysplasia of the hip through standard hip 3D CT reconstruction.Methods From June 2010 to January 2013,there were 62 patients with 68 hips (8 hips of 6 male cases,56 female cases of 60 hips) diagnosed as acetabular dysplasia in our hospital,with an average age of 53.7±5.8 years old (range,47-59 years).According to Crowe classification,there were 14 cases (17 hips) of Crowe type Ⅰ,17 cases (17 hips) of Crowe type Ⅱ,15 cases (17 hips) of Crowe type Ⅲ,and 16 cases (17 hips) of Crowe type Ⅳ.Through standard hip 3D CT reconstruction,Harris nest in the pelvic side 3D image was marked,and the coronal and horizontal position of acetabular rotation center was determined by using the cross axis; secondly,in the anteroposterior 3D image (by gray level adjustment to the shape of X ray perspective effect) through Ranwant triangulation,sagittal position of the center of rotation of the hip joint was determined; finally,the acetabular rotation center in the acetabular horizontal reconstruction plane.The bone stock of anterior and posterior columns of acetabular was observed and acetabular anteversion,front cover angle,rear cover angle and medial wall thickness were measured.Results 1) With Crowe type increased,acetabular anteversion angle gradually increased as well,and there was a positive correlation between them with statistically significant (P＜0.05) except in Crowe Ⅰ and Ⅱ group.2) With Crowe type increased,anterior acetabular coverage angle was significantly decreased; the mean anterior acetabular coverage angle of Crowe Ⅲ and Ⅳ groups was less than 50°.3) With Crowe type increased,posterior acetabular coverage angle was decreased significantly as well the mean posterior acetabular coverage angle of Crowe Ⅲ and Ⅳ groups was less than 90°.4) With Crowe type increased,acetabular medial wall thickness was increased significantly.Conclusion Adult acetabular morphology changes between different Crowe types in patients with developmental dysplasia of the hip.For acetabular reconstruction of Crowe Ⅰ and Ⅱ,we could make full use of the acetabular bone stock of anterior and posterior column; for acetabular reconstruction of Crowe Ⅲ and Ⅳ,we could moderately shift the acetabular center superiorly and (or) medially.

Objective To investigate relationship between polyethylene wear and decrease of femoral offset after total hip arthroplasty (THA).Methods Ninety patients who had undergone unilateral THA were recruited in this study.Coreldraw 12.0 software was used to measure change of femoral offset on the basis of immediate anteroposterior radiographies of bilateral hip after THA.In the light of the decreasing value of femoral offset (F),all patients were equally into 5 groups:F＜2 mm,2≤F≤4 mm,4＜F≤6 mm,6＜F≤8 mm and 8＜F≤ 10 mm.At final follow up,some parameters about polyethylene wear were measured by using Coreldraw 12.0 software on the basis of anteroposterior radiographies of bilateral hip.Results The linear wear volume was 0.72±0.13 mm in group F＜2 mm,0.78±0.11 mm in group 2≤F≤4 mm,0.87±0.09mm in group 4＜F≤6 mm,0.99±0.09 mm in group 6＜F≤8 mm,and 1.17±0.15 mm in group 8＜F≤10 mm.The linear wear rate was 0.132±0.025 mm/yr in group F＜2 mm,0.139±0.019 mm/yr in group 2≤F≤4 mm,0.159±0.029 mm/yr in group 4＜F≤6 mm,0.183±0.032 mm/yr in group 6＜F≤8 mm,and 0.213±0.023 mm/yrin group 8＜F≤ 10 mm.The linear wear angle was 5.0°±3.5° in group F＜2 mm,3.2°±3.8. in group 2≤F≤4mm,-4.3°±4.9° in group 4＜F≤6 mm,-8.7°±4.1° in group 6＜F≤8 mm,and -13.0°±4.7° in group 8＜F≤ 10mm.For three parameters above,there were significant differences between groups,except between group F＜2 mm and group 2≤F≤4 mm.Conclusion The femoral offset should be restored to its anatomic status in THA to avoide superior lateral displacement of center of the femoral head,which could result in uneven stress distribution and increase polyethylene wear.

BACKGROUND:It is generaly believed that the spine wil be extended, and vertebral muscle atrophy, bone loss of vertebral body, increased height and area of intervertebral disc, changes of composition of intervertebral disc wil occur in the condition of weightlessness. These are likely to be the cause of high incidence of low back pain. OBJECTIVE:To observe changes in lumbar spine bone microstructure analysis of simulated weightlessness on rhesus lumbar spine biomechanics. METHODS:Fourteen young rhesus monkeys were randomly divided into two groups: control group (n=7;free activities in the cage during the experiment), and experimental group (n=7; the use of head-down-10° on a special bed by bundle lying to simulate weightlessness). RESULTS AND CONCLUSION:(1) The results of Micro-CT examination: in the experimental group, structure model index in trabecular bone of increased. Trabecular bone changed from plate-like to the rod-like change. The intersection number of bone tissue in unit length to non-bone tissue declined. The average width of the canal between the trabecular bone increased, suggesting that there have been signs of osteoporosis in the experimental group. (2) Under an optical microscope, in the experimental group, bone hyperplasia line was disordered and irregular. Thick endplate trabecularbone became smal, shalow, and arranged substantialy perpendicular to the direction of trabecular bone and cartilage endplate. The closer the endplate surface, the smaler trabecular bone was. Compared with the control group, these smal trabecular bones were thin and curved. Bone marrow cavity was oval. The degree of the connection between the trabecular bones is poor, reflecting the structural characteristics of significant osteoporosis. (3) It is indicated that weightlessness affected the biomechanical properties of rhesus lumbar motion unit.

There are some shortcomings of animal experiments applied in chemical toxicity testing, such as long period, large cost, species differences and dose differences, which limit the use of animal experiments' results in predicting human toxicity.Accordingly, we established a toxicity testing alternative screening system in line with the toxicity endpoints which required in chemical safety evaluation and risk assessment (genotoxicity, carcinogenicity, reproductive toxicity, acute toxicity and general toxicity) based on 3R principles (replacement, reduction, refinement) for animal experiments.This system covers most of the endpoints of toxicity assessment, and molecular biology technology was also applied to integrate the toxicity test, as well as some operation was optimized in order to shorten the experimental period, reduce experimental costs, improve animal welfare.Furthermore, the results from the screening system have higher clinical relevance because it is based on the toxicity mechanisms.

Objective To assess the feasibility of urinary PEBP1 as a potential biomarker of congenital obstructive hydronephrosis.Methods A total of 60 children with hydronephrosis (severe and mild hydronephrosis groups) and 30 healthy children were enrolled to define the expression of PEBP1 in bladder urine samples by ELISA.Correlation analysis and ROC analysis were used to define the expression of PEBP1 and diagnostic profile in identifying children with impaired split renal function.Results The PEBP1 levels decreased significantly and positively correlated with split renal function in study group before surgery (r =0.818,P ＜ 0.05).One month after surgery,it increased significantly.An area under the curve for PEBP1 protein of 0.89 with a best cutoff value of 0.521 ng/mg cr and the impaired split renal function decreased to 30％ or less (sensitivity 80％,specificity 90％) was found.Conclusion Decreased PEBP1 may be a potential biomarker for the diagnosis of congenital hydronephrosis in children,and it can also be used to assess the severity of the disease and the therapeutic effect.