ABSTRACT
Melorheostosis is a rare disorder of osteopathia. The clinical characteristics of melorheostosis in children is totally different from that in adults. The radiographic features of melorheostosis include the hyperostosis in endosteal on the one side of the cavum medullare and formed streakiness. The soft tissue contracture of the limb and joint deformities are the symptoms of melorheostosis. Here, the authors reported a melorheostosis case of 6 years old girl who suffered from severe valgus deformity of the right knee with permanent patellar dislocation. A surgical stabilization was applied with lateral soft tissue release, medial soft tissue stabilization and transferred the vastus medialis laterally (kinetic stability). After 19 years follow up postoperatively, the limb developed well in satisfied alignment with good function of knee joints, even participated in some sports activities. Other authors reported a similar case of melorheostosis with surgical treatment and achieved good outcomes in limb realignment and reduction. The further suggested that the surgical treatment should be produced before epiphyseal closure.
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Objective To investigate the mid-and long-term effects of metal-on-metal hip resurfacing arthroplasty (HRA),and to analyze its related factors.Methods A total of 64 patients (81 hips) who underwent metal-on-metal HRA from June 2005 to January 2013 were recruited in the present study.There were 35 males (44 hips) and 29 females (37 hips) with the mean age of 48.26±10.45 years (20-65 years),including 47 unilateral and 17 bilateral HRAs.The cohort consisted of osteoarthritis secondary to the developmental dysplasia of the hip (23 cases,29 hips),necrosis of the femoral head (19 cases,22 hips),osteoarthritis (8 cases,10 hips),rheumatoid arthritis (5 cases,9 hips),ankylosing spondylitis (6 cases,8 hips),pigmented villonodular synovitis (2 cases,2 hips) and Otto's disease (1 case,1 hip).During the follow-up duration,radiographic features,including acetabular inclination angle,stem-femoral shaft angle,component loosening,osteolysis,femoral neck narrowing and heterotopic ossification,were evaluated by hip X-rays in straight and froglike position.The size and type of pseudotumor were assessed by MRI and ultrasonography.Clinical efficacy was evaluated by Harris hip score and the University of California at Los Angeles (UCLA) hip score.Considering revision surgery as the end point,the component survivorship was calculated.Results The mean follow-up was 7.98±2.21 years,ranging from 5.0 to 12.8 years.The mean postoperative Harris hip score (92.01 ±5.69) was higher than the preoperative score (41.93 ±9.09).The mean postoperative UCLA pain,walking,function,activity scores (9.37±0.86,9.14± 1.01,8.77± 1.09,6.47± 1.27,respectively) were improved when compared with the preoperative UCLA scores (3.57± 1.23,5.99± 1.30,5.00± 1.01,3.84± 1.41,respectively).The postoperative flexion,abduction and adduction,medial and lateral rotation of the hip was larger than the preoperative ones.Complications occurred in 10 hips (12.3％,10/81).Seven patients (8 hips) experienced early and intermediate complications,including one intraoperative femoral nerve injury,one deep femoral artery and saphenous nerve injuries during the same surgery,one unexplained pain of hip,one femoral neck fracture,three hips of heterotopic ossification,and one pseudotumour.There were mid-and long-term complications in two hips,including one narrowing of the neck and one pseudotumour which was occurred at 9 years.There was one patient (2 hips) underwent revision surgery twice at 5 months and 9 years.The former cause of revision was femoral neck fracture and the latter one was pseudotumour.The Kaplan-Meier survivorship was 98.8％ at five years,and 95.0％ at ten years.Conclusion Patients who underwent metal-on-metal HRA could obtain good mid and long-term results.Pseudotumour and unexplained pain of the hip are critical factors which can affect the mid-and long-term results and survivorship of metal-on-metal HRA.
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Clinical data and radiological findings of 78 patients with distal radial fractures,who underwent plain X-ray film and muhislice CT (MSCT) examinations,were retrospectively analyzed.Twenty nine associated carpal bone factures were detected on X-ray film in 21 cases;while 47 associated carpal bone fractures were detected on MSCT in 29 cases (P ＜ 0.05).The missed diagnosis rate of X-ray was 38％.Results indicate that MSCT can significantly improve the detect rate,which should be recommended for diagnosis of associated carpal bone fractures in distal radial fractures.
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Objective To study the risk factors of MRI for the prediction of collapse in patients with avascular necrosis of the femoral head.Methods Twenty-two patients (39 hips) diagnosed avascular necrosis of femoral head by MR were enrolled in our study.The following MR appearances were evaluated:bone marrow edema,joint fluids,signal intensity and location of the lesion.The volume and surface area of the necrosis zone were calculated.The time of follow-up was 18-84 months (median,25 months).Logistic regression analysis was used to predict the risk factors by SPSS 13.0.The maximum value of Youden index was selected as the critical point to predict the collapse of femoral head and to define the sensitivity,specificity and accuracy.Results In the 39 hips with femoral head necrosis,21 hips had collapse.Bilateral collapse occurred in 5 cases.In 25 hips with the necrosis surface larger than 25％,collapse occurred in 21 (84％); In 8 hips with the volume of femoral head necrosis larger than 30％,collapse occurred in all cases; 1n 33 hips with the necrosis locating at the superolateral quadrant,collapse occurred in 21 (63.6％); In 22 hips with necrotic areas showing heterogeneous signal intensity,collapse occurred in 18(81.8％) ;In 25 hips with large amount of joint effusion,collapse occurred in 16 (64％) ;in 18 hips with bone marrow edema,collapse occurred in 13 (65％).Joint fluid,heterogeneous signal intensity and lesions in the superolateral quadrant,volume ratio,and area ratio were the high risk factors,while bone marrow edema was a relatively low risk factor.The area under ROC curves for area ratio of NASA was greater than that for volume ratio (0.987 vs 0.902).When the critical value for area ratio was 26.7％,the true positive rate was 95.2％,true negative rate was 94.4％,and Youden's index was 0.896.Conclusions The collapse of necrosis of femoral head may result from many factors.The femoral head was easy to collapse when it had large enough area of necrosis and mixed signal intensity,a large amount of joint effusion,bone marrow edema,and superolateral quadrant location.The critical value for area ratio to predict the collapse of femoral head was about 26.7％.The area ratio is more accurate than volume ratio in predicting the collapse of necrosis of femoral head.
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Objective To detect the MRI manifestations and discrimination of tuberculous spondylitis and pyogenic spondylitis with atypical features in early stage. Methods Six patients with pathologically proved tuberculous spondylitis and 7 patients of pyogenic spondylitis with atypical clinical features and were included. MRI features of the vertebral bodies, intervertebral discs, paraspinal soft tissues and their enhancement patterns were analyzed. Chi-Square test was used to compare the MRI features of two diseases. Results Patients with pyogenic spondylitis had a significantly higher incidence of disk space narrowing (8 intervertebral bodies), abnormal signal in superior/inferior of vertebral body (12 intervertebral bodies) and endplate with high signal (13 intervertebral bodies), which were not seen in the patients with tuberculosis spondylitis (P<0.05).Patients with tuberculous spondylitis had a significantly higher incidence of local abnormal signal in anterior of vertebral body (4 intervertebral bodies) and paraspinal abscess spanning vertebral body (5 intervertebral bodies), while none of them was found in patients with pyogenic spondylitis (P<0.05). Conclusion MRI is accurate for the differentiation of tuberculous spondylitis and pyogenic spondylitis with atypical feature in early stage.
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Objective To set up the 3D-finite element(FE)model of normal acetabulum-cartilage-femoral head,so that to provide an effective model for biomechanical analysis of femoral head.Methods(1)The hip joint in one healthy adult male volunteer was scanned by MRI at coronal section.The 3D reconstruction model of acetabulum-cartilage-femoral head was constructed with MATLAB and ANSYS software.(2)The 3D orthotropy finite element model of the acetabulum-cartilage-femoral head was constructed by givig the corresponding material parameters to the different structures of the model of acetabulum-cartilage-femoral head and divided into networks through ANSYS software.(3)The standing status was imitated on the model to set boundary condition and loading and then calculated.The effect of the model was evaluated in comparison with that of literature.Results A 3D orthotropy FE model of acetabulum-cartilage-femoral head was established successfully,including 89 961 points of 448 159 units.The maximal displacement was on the femoral head,and the maximal Von Mises stress was on the femur neck.The stress analysis was the same as the results of literature and the actuality.Conclusion A 3D orthotropy FE model of acetabulum-cartilage-femoral head can be setup based on MRI images,which can provide a reasonable and effective model for biomechamical analysis of femoral head.
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Objective To investigate the value of dynamic contrast-enhanced magnetic resonance imaging ( DCE-MRI) in differentiating serological negative early stage rheumatoid arthritis (RA) from osteoarthritis (OA)in hand. Methods Plain MRI, enhanced MRI of whole hand and DCE-MRI of single slice were performed in 53 patients suspected of RA or OA and 18 healthy volunteers. Twenty-three of them were diagnosed as RA,including 18 cases of serological negative RA and 18 of them were diagnosed as OA after 3 to 6 months follow-up. The contrast rate,slope, thickening of synovial membrane were measured on DCE-MRI in three groups and the MRI findings were also were detected in both RA and OA groups. The contrast rate and slope of synovial membrane were compared among three groups using rank sum test. The thickening of synovial membrane were compared among three groups using variance analysis. MRI signs of RA and OA group were evaluated with rank sum test Results The dynamic contrast rate of synovial membrane in RA group,OA group and control group was(100.78±61.96)%,(40.44±15.43)% and (23.56±9.14)%,respectively.Individually,RA group to OA group,u=3.101,P=0.002;RA group to control group,u=4.669,P=0.000;OA group to control group,u=3.482,P=0.000.The slope of contrast curve of synodal membrane of RA group,OA group and control group was 72.50°±13.34°,45.39°±9.94°,14.56°±5.75°,respectively.Individually,RA group to OA group,u=8.002,P=0.000;RA group to control group,u=17.102,P=0.000;OA group to control group,u=9.100,P=0.000.The synovial membrane thickening of RA group,OA group and control group was(3.3±0.5),(2.8±0.7)and (1.4±0.6)mm,respectively.Individually,RA group to OA group,q=2.622,P=0.011;RA group to control group,q=9.583,P=0.000;OA group to control group,q=6.961,P=0.000.Conclusion The quantitative index of DCE-MRI,including contrast rate and synovial membrane thickening may provide useful information for differentiating OA from semlogical negative early stage RA.The contrast rate and thickening of synovial membrane in RA group are higher than those in OA group.Many signs of MRI Can help differentiate OA from RA.
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Objective To study the scanning technique of 16-detector multic-slice spiral CT (MSCT) for combined pulmonary artery and deep vein of lower limb in pulmonary thromboembolism (PE) patients.Methods Forty suspected pulmonary thromboembolism patients were performed both pulmonary artery angiography (CTA) and indirect deep vein venography (CTV) on 16-detector MSCT. The parameters of the latter as following :total contrast volume 120-150 ml, injection rate 4.0-4.5 ml/s (from antecubital vein), delay time 4.0 for CTA 20-23 s, CTV 120-180 s, collimation for CTA 1.25 mm and 0.625 mm, CTV 2.5 mm, scan range of CTV: from popliteal vein to the level of bilateral renal vein into the inferior vena cava. Postprocessing include MPR, MIP, and VR. The test was used to analyzed the images.Results Twenty five patients had both pulmonary thromboembolism(PE) and deep vein thromboembolism (DVT), 8 patients had only DVT, 2 had only PE, and 5 had neither. There was no difference between different collimation in depicting thrombus. The CT value number of enhanced pulmonary artery and lower deep vein was obviously higher than the thrombus. The value of MPR, MIP, VR for PE was 100%, 100%, and 65%, The value of MPR,MIP,VR for DVT is 100%, 60%, and 50%.Conclusion The technique of combined pulmonary CTA and deep vein CTV of 16-detector MSCT will provide a new modality for pulmonary thromboembolism patients.