Study Design: Retrospective cohort study. Objectives: To review our treatment experience and to investigate the process of this disease. Methods: Clinical data of AARF patients, who received closed reduction, was retrospectively reviewed. Patients were divided into 2 groups according to the length of delay (Group I: 1 month ≤ delayed time < 3 months), Group II (delayed time < 1 months). The correlation between the length of delayed time and clinical recovery (CR), radiological recovery (RR), and total recovery time were measured. The atlantodental interval (ADI), lateral mass-dens interval (LDI) and lateral joint space (LJS) were compared at admission and final follow-up. Results: 30 children (12 girls and 18 boys) with AARF had received conservative treatment. The mean age at initial treatment was 8.13-year-old, ranging from 5 to 14. The mean follow-up time was 26.93 months (range, 6-87 months). The average length of delayed time was 28.53 days (range, 2-80 days). When the LDI, LJS, and ADI differences are compared at admission and the final visit, the differences are reduced significantly on LDI and LJS. A positive correlation is observed between the length of the delay and CR time and total recovery time (r = 0.63, p = 0.00 and r = 0.47, p = 0.01) respectively. Conclusions: Pediatric AARF patients who have a delay time < 3 months can be treated with closed reduction successfully. The longer the delayed time, the longer the traction time, but the cervical collar time is almost the same. The LDI and LJS on the anteroposterior of X-rays are convenient to estimate the progress of this condition during the treatment.

Background: Exogenous surfactant (S) therapy improved mortality and morbidity of premature babies with respiratory distress syndrome. The commercial S preparation used in our NICU is natural "bovine" type. The adverse effects of this therapy have not been clarified yet. Objective: To estimate the early and later risks of S therapy for respiratory distress syndrome (RDS). Methods: Data from all premature newborns with or without RDS treated or not with S in our NICU the last 10 years were analyzed. The incidence and the relative risk(RR) of the lung and intracerebral hemorrhage as well as of the infection were calculated. Three hundred ninenty three of them accepted to participate in a retrospective study and were examined for allergic disorders, such as allergic rhinitis, asthma and adverse food reactions. Results: Three thousands forty premature newborns graduated our NICU from 1994 to 2004.Pulmonary hemorrhage was observed in the 57 of the 330 newborns with RDS who received S and the 6 over 198 of those newborns untreated with S,chi squaredϭ19.489, pϭ0.00001,RRϭ5.756. Intraventricular hemorrhage was diagnosed in 106 of the 281 and 20 over 184, respectively, chi square ϭ24.629, pϭ0.00001,RRϭ3.490.Infection in 115 of 272 and 87 in 117,respectively, chi squared ϭ9.291,pϭ0.00167,RRϭ1.768. Positive history of allergy was estimated in the 44% of the children treated with S for RDS and in the 25% of those with RDS not treated with S, chi squaredϭ11.363, pϭ0.000749.From the premature babies without RDS allergy was noted in 28%,xϭ0.8061,pϭ0.3692. Conclusion: Despite the undoubtfull benefits of the S therapy for RDS attention should be paid to its possible early and late adverse effects. The S therapy increases the risk for severe even lethal complications such as pulmonary or intraventricular hemorrhage and infection. It is impressive the almost twofold increase in the incidence of allergy during childhood in babies treated with S compared to non-treated ones. Prospective clinical trials and basic research would help to minimize the early risks and optimize late prognosis in newborns treated with S.

Background: Developmental dysplasia of the hip (DDH) is the most common deformity of the lower extremity in children. The biomechanical change during closed reduction (CR) focused on cartilage contact pressure (CCP) has not been studied. Thereby, we try to provide insight into biomechanical factors potentially responsible for the success of CR treatment sand complications by using finite element analysis (FEA) for the first time.Methods: Finite element models of one patient with DDH were established based on the data of MRI scan on which cartilage contact pressure was measured. During CR, CCP between the femoral head and acetabulum in different abduction and flexion angles were tested to estimate the efficacy and potential risk factors of avascular necrosis (AVN) following CR.Results: A 3D reconstruction by the FEA method was performed on a sixteen months of age girl with DDH on the right side. The acetabulum of the involved side showed a long, narrow, and "flat-shaped" deformity, whereas the femoral head was smaller and irregular compared with the contralateral side. With increased abduction angle, the stress of the posterior acetabulum increased significantly, and the stress on the lateral part of the femoral head increased as well. The changes of CCP in the superior acetabulum were not apparent during CR. There were no detectable differences in terms of pressure on the femoral head.Conclusions: Severe dislocation (IHDI grade III and IV) in children showed a high mismatch between the femoral head and acetabulum. Increased abduction angle corresponded with high contact pressure, which might relate to AVN, whereas increased flexion angle was not. Enhanced pressure on the lateral part of the femoral head might increase the risk of AVN.

Background: Developmental dysplasia of the hip (DDH) is the most common deformity of the lower extremity in children, and the etiology remains unclear. The biomechanical change during closed reduction (CR) focused on cartilage contact pressure (CCP) has not been studied. Thereby, we try to provide insight into biomechanical factors potentially responsible for CR treatment success and complications by using finite element analysis (FEA) for the first time.Methods: Finite element models of one patient with DDH were established based on the data of MRI scan on which cartilage contact pressure was measured. During CR, CCP between the femoral head and acetabulum in different abduction and flexion angles were tested to estimate the efficacy and potential risk factors of avascular necrosis (AVN) following CR.Results: A 3D reconstruction by the FEA method was performed on a sixteen-month-old girl with DDH on the right side. The acetabulum of the involved side showed a long, narrow, and "plate-shaped" deformity, whereas the femoral head was smaller and irregular compared with the contralateral side. With increased abduction angle, the stress of the posterior acetabulum increased significantly, and the stress on the lateral part of the femoral head increased as well. The changes of CCP in the superior acetabulum were not apparent during CR. There were no detectable differences in terms of pressure on the femoral head.Conclusions: Severe dislocation (IHDI grade III and IV) in children showed a high mismatch between the femoral head and acetabulum. Increased abduction angle corresponded with high contact pressure, which might relate to avascular necrosis, whereas increased flexion angle was not. Enhanced pressure on the lateral part of the femoral head might increase the risk of AVN.

Background Developmental dysplasia of the hip (DDH) is the most common deformity of the lower extremity in children, and the etiology remains unclear. The biomechanical change during closed reduction (CR) focused on cartilage contact pressure (CCP) has not been studied. Thereby, we try to provide insight into biomechanical factors potentially responsible for CR treatment success and complications by using finite element analysis (FEA) for the first time. Methods Finite element models of one patient with DDH were established based on the data of MRI scan on which cartilage contact pressure was measured. During CR, CCP between the femoral head and acetabulum in different abduction and flexion angles were tested to estimate the efficacy and potential risk factors of avascular necrosis (AVN) following CR. Results A 3D reconstruction by the FEA method was performed on a sixteen-month-old girl with DDH on the right side. The acetabulum of the involved side showed a long, narrow, and "plate-shaped" deformity, whereas the femoral head was smaller and irregular compared with the contralateral side. With increased abduction angle, the stress of the posterior acetabulum increased significantly, and the stress on the lateral part of the femoral head increased as well. The changes of CCP in the superior acetabulum were not apparent during CR. There were no detectable differences in terms of pressure on the femoral head. Conclusions Severe dislocation (IHDI grade III and IV) in children showed a high mismatch between the femoral head and acetabulum. Increased abduction angle corresponded with high contact pressure, which might relate to avascular necrosis, whereas increased flexion angle was not. Enhanced pressure on the lateral part of the femoral head might increase the risk of AVN.