ObjectiveTo investigate the effectiveness of internal and external lysis combined with Ilizarov external fixation technology for severe knee pathological flexion contracture deformity in children.MethodsA retrospective analysis was made on 12 children (12 knees) with severe knee pathological flexion contracture deformity who were treated with internal and external lysis and Ilizarov external fixation between August 2012 and January 2017. There were 9 boys and 3 girls with an age of 3-12 years (mean, 8.4 years). There were 8 cases of tuberculosis, 3 cases of haemophilia A, and 1 case of residual deformity after extensive hemangioma drug injection. The disease duration ranged from 5 months to 4 years, with an average of 20.3 months. The degree of knee contracture was (67.42±23.30)°, and the range of motion of knee was (38.33±14.98)°. The preoperative Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score was 78.42±15.57. The complication was observed after operation, and the degree of knee contracture, range of motion, and WOMAC score at 3 months and 1 year after operation were recorded and compared with those before operation.ResultsThe operations completed successfully in all children. All the 12 cases were followed up 9-24 months (mean, 14.5 months). All incisions healed by first intention after operation. The knee function of all children improved significantly and the weight-bearing walking function of the lower limbs restored. The degree of knee contracture, range of motion, and WOMAC score were significantly improved at 3 months and 1 year after operation (P<0.05), but there was no significant difference between 3 months and 1 year after operation (P>0.05).ConclusionFor severe knee pathological flexion contracture deformity in children, application of internal and external lysis combined with Ilizarov external fixation has advantages, such as small trauma, rapid recovery, and early postoperative knee function training, and good effectiveness.
Portal hypertension (PHT) is a common complication of liver cirrhosis, which could be measured by the means of portal vein pressure (PVP). However, there is no report about an effective and reliable way to achieve noninvasive assessment of PVP so far. In this study, firstly, we collected ultrasound images and echo signals of different ultrasound contrast agent (UCA) concentrations and different pressure ranges in a low-pressure environment based on an in vitro simulation device. Then, the amplitudes of the subharmonics in the echo signal were obtained by ultrasound grayscale image construction and fast Fourier transform (FFT). Finally, we analyzed the relationship between subharmonic amplitude (SA) and bionic portal vein pressure (BPVP) through linear regression. As a result, in the pressure range of 7.5–45 mm Hg and 8–20 mm Hg, the linear correlation coefficients (LCC) between SA and BPVP were 0.927 and 0.913 respectively when the UCA concentration was 1∶3 000, and LCC were 0.737 and 0.568 respectively when the UCA concentration was 1∶6 000. Particularly, LCC was increased to 0.968 and 0.916 respectively while the SAs of two UCA concentrations were used as the features of BPVP. Therefore, the results show a good performance on the linear relationship between SA and BPVP, and the LCC will be improved by using SAs obtained at different UCA concentrations as the features of BPVP. The proposed method provides reliable experimental verification for noninvasive evaluation of PVP through SA in clinical practice, which could be a guidance for improving the accuracy of PVP assessment.