Effects of Total Hip Arthroplasty on Proximal Femoral Bone Remodeling / 医用生物力学

Objective To analyze the influence of total hip arthroplasty (THA) on the process of proximal femoral bone remodeling by using the Wolff bone remodeling theory. Methods According to control equation of bone remodeling, the program of bone remodeling was written in Python language. Preoperative femur model and postoperative femur and prosthesis finite element models were established respectively in ABAQUS software. The process of bone reconstruction before and after THA operation was compared to analyze the effect of prosthesis implantation on mechanical properties of the femur in the middle and long term after THA operation. Results The stress in proximal femur continued to decrease after prosthesis implantation, and the stress site was transferred from the femoral head to the prosthesis, resulting in an obvious stress shielding phenomenon. Bone loss in the stress shielding area was serious. The femoral shaft cortical bone became thinner and the stress shielding was relieved. The medial side at the bottom of the prosthesis was compressed, and the stress was significantly higher than that of the lateral side, where the bone was unevenly distributed. Conclusions After THA operation, obvious stress shielding occured at proximal medial side of the femur, leading to bone loss and prosthesis loosening. The difference in stress levels on both sides at the bottom of the prosthesis resulted in an uneven bone distribution, causing the discordance between the prosthesis and the femur, as well as postoperative pain in the middle part of the thigh.

Identification of pathogenic variant in a Chinese pedigree affected with non-syndromic cleft lip and palate / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a Chinese pedigree affected with non-syndromic cleft lip and cleft palate (NSCLP).@*METHODS@#With informed consent obtained, members of the pedigree were subjected to clinical examination and history taking to exclude syndromic cleft lip and palate. One affected member was subjected to whole-exome sequencing and bioinformatics analysis. Candidate variant was verified by Sanger sequencing and co-segregation analysis of her family members and 100 unrelated healthy individuals.@*RESULTS@#Whole-exome sequencing and co-segregation analysis showed that all affected members of this pedigree have carried a heterozygous missense c.253A>G (p.Cys85Arg) variant in exon 4 of the IRF6 gene, which has co-segregated with the phenotype and was not found among the 100 unrelated healthy individuals.@*CONCLUSION@#The missense c.253A>G variant in exon 4 of the IRF6 gene probably underlay the NSCLP in this pedigree.

Clinical significance of detecting transmural dispersion of repolarization in patients with hypertrophic cardiomyopathy / 中国医师进修杂志

Objective To explore the changes and clinical significance of transmural dispersion of repolarization (TDR) in patients with hypertrophic cardiomyopathy (HCM). Methods Seventy-two patients with HCM (observation group) and 72 healthy subjects (control group) in Shengjing Hospital of China Medical University were selected from January 2015 to October 2017. The 12-lead conventional electrocardiogram was performed on enrolled personnel in 2 groups to measure T-peak T-end (TpTe), correct the QT interval (QTc), QT interval dispersion (QTd) and TpTe/QTc. The observation group underwent 24 h dynamic electrocardiography. The patients were divided into ventricular arrhythmia subgroup and non- ventricular arrhythmia subgroup according to the results of 24 h dynamic electrocardiography, and the TpTe, QTc, QTd and TpTe/QTc were compared. Results The TpTe, QTc, QTd and TpTe/QTc in observation groups were significantly higher than those in control group:(112.5 ± 11.2) ms vs. (105.6 ± 9.2) ms, (396.5 ± 13.5) ms vs. (385.3 ± 12.5) ms, (36.5 ± 6.4) ms vs. (32.4 ± 5.4) ms and 0.289 ± 0.016 vs. 0.262 ± 0.015, and there were statistical differences (P＜0.05). In observation group, the 24 h dynamic electrocardiogram result showed that 47 patients had ventricular arrhythmia (ventricular arrhythmia subgroup) and 25 patients had not ventricular arrhythmia (non-ventricular arrhythmia subgroup). The TpTe, QTc, QTd and TpTe/QTc in ventricular arrhythmia subgroup were significantly higher than those in non-ventricular arrhythmia subgroup: (114.4 ± 14.5) ms vs. (110.3 ± 12.2) ms, (402.5 ± 15.2) ms vs. (392.0 ± 12.1) ms, (37.5 ± 6.2) ms vs. (35.4 ± 6.5) ms and 0.292 ± 0.016 vs. 0.285 ± 0.015, and there were statistical differences (P＜0.05). Conclusions The values of TpTe, QTc, QTd and TpTe/QTc reflect the increase of transmural dispersion of repolarization in patients with HCM, and have a certain predictive effect on ventricular arrhythmia.

Application of Z-form plasty with a nasal mucous membrane and alar cartilage flap to repair severe secondary nasal deformity after cleft lip operation / 中华医学美学美容杂志

Objective To investigate a repair method for unilateral complete cleft lip nasal deformities.Methods Based on the fullness of healthy nasal wing,Z-form plasty was designed with a nasal mucous membrane and alar cartilage flap,to prolong its curtate length of the deformed side through overlapping transposition,and then with suspension of the custom-crafted nasal wing to replace its abnormal structure,subsequently,to recover the normal anatomic structure of the nosewing,and to get the nasal deformity repaired.Results A total of 12 patients with the severe nasal deformity were treated by this method.and all had satisfactory results.Conclusion This technique is a good choice for repairing the severe secondary nasal deformity after single complete cleft lip operation.