Objective To evaluate the clinical valueof the revision of total hip replacement(THR), to analyse the reason of the rev isions, and to discuss the main difficulties and measures to manage it.Methods From June 1998 to January 2002, 15 cases (15 hips) were revised on totalhip replacement. The reasons for revision in the cases were as follows:failure of primary operative techenique, loosening and sinking of the components, displacement of the prosthesis, erosion of the acetabulum, as well as fracture of the femoral stem. The main difficulties of the revision were:poor health condition of the patients; the remove of the prosthesis of the primary THR,especially the broken femoral stem and the cements; the loss of localbone. The measures to remove the broken femoral stem were described.ResultsAll cases were followed up 2.4 years on average: 2 patients died from heart disease and cerebrovascular disease respectively, while the good results were achieved in the others.No infection, dislocation, loosening, and other complications occurred. The good effects were related with following factors:mild degree of illness; no severe bone defect; most of the first femoral head replacement.Conclusion The revision of THRis a more difficult operation, so that the special instrument and equipment andoperative experience are required.
Objective To explore the reliability and accuracy of the arbitrary point method for measuring the anteversion angle of acetabular prosthesis after total hip arthroplasty (THA) based on pelvic X-ray films. Methods The clinical data of 23 patients (25 hips) who underwent THA between December 2018 and September 2023 and met the selection criteria were retrospectively analyzed. Among them, there were 16 males and 7 females, with an average age of 57.6 years (range, 34-81 years); 13 hips had THA on the left side and 12 on the right side. There were 19 cases (21 hips) of osteonecrosis of the femoral head, 2 cases (2 hips) of femoral neck fractures, 1 case (1 hip) of developmental dysplasia of the hip, and 1 case (1 hip) of osteoarthritis. After THA, all patients underwent X-ray examination and CT scan. Three physicians measured the anteversion angle of acetabular prosthesis using the arbitrary point method and the CT measurement method respectively, and repeated the measurements three times. The results of the two measurement methods were compared, and the intraclass correlation coefficient (ICC) was employed to assess the reproducibility of the methods. Results The anteversion angles of acetabular prosthesis were (15.87±7.73)° measured by the arbitrary point method, and (15.31±7.89)° measured by CT measurement method. There was no significant difference between the two methods (t=1.515, P=0.143). The ICC of the measurement results by the arbitrary point method for the three physicians were 0.97 (P<0.001), 0.96 (P<0.001), and 0.96 (P<0.001), respectively; and the ICC of the measurement results by CT method were 0.93 (P<0.001), 0.93 (P<0.001), and 0.94 (P<0.001), respectively. Conclusion The arbitrary point method for measuring the anteversion angle of acetabular prosthesis after THA based on pelvic X-ray film is easy to operate, accurate, and has high reproducibility.
Objective To evaluate the operative methods and therapeutic effects of nasal septum cartilage-sil ica gel complex for two-stage repair of nasal deformities of unilateral cleft l ip. Methods From June 2001 to June 2007, 38 cases of secondary nasal deformity and septum deviation of cleft l ip were treated with transplanting nasal septum cartilage-sil ica gelcomplex. Among of them, there were 21 males and 17 females, aging 14-23 years with an average of 17.6 years. All cases were with nasal deformities of unilateral cleft l ip, including 21 cases of complete cleft l ip and 17 cases of incomplete cleft l ip. The locations were left side in 26 cases and right side in 12 cases. Nasal deformities were columella nasi deflexion, flattened nasal tip, pteleorrhine and alanasi collapse. The patients received 1-4 times operations, and the interval of two operations was 3-10 years (mean 5.5 years). According to nasal deformity, the nasal septum cartilage of 1.8 cm × 1.2 cm was cut, and transplanted into the nose point phantom surface forming “the shield” to extend nose column and to raise the tip of the nose. At the same time the nasal tip fat-connective tissue flap graft with fat knot was given. After fixation, the nasal alar cartilage and soft tissues were reduced to normal position. Results Primary heal ing of the incisions was achieved in all cases. The nasal deformity was corrected. The postoperative follow-up period was 12-18 months with an average of 15.6 months. All the patients of regional cartilage scars had no compl ication. The figure of nose was sl inky, the height of apex of nose and the shape of nose was natural,the apex of nose, nasal ala, nostrils and nasal columella were satisfactory [(the results were satisfactory in 30 cases (78.9%), general in 8 cases (21.1%)]. The nose department overall esthetics shape was improved in all the patients, no compl ications of the phantom sl iding, shifting and exposure, hemorrhage and infection occurred. Conclusion The nasal septum cartilagesil ica gel complex to repair the nasal deformities of unilateral cleft l ip is an ideal operation style.
In recent years, the field of cardiovascular surgery has undergone revolutionary changes and made rapid progress in various aspects, bringing more hope and possibilities for the health and well-being of patients. The constant emergence of new technologies brings new opportunities and hope, as well as constant challenges to past concepts. This article aims to provide a comprehensive overview of the latest developments in cardiovascular surgery in recent years, especially since 2023. It introduces cutting-edge knowledge and technologies in the field of cardiovascular surgery, including lifelong management of aortic valve disease, artificial valves, mitral valves, treatment options for hypertrophic obstructive cardiomyopathy, heart transplantation, left ventricular assist, coronary artery surgery, cardiac structural interventions for chronic heart failure, aortic dissection, and comprehensive surgical treatment of atrial fibrillation. It also analyzes and explores future development directions in depth, aiming to provide useful references and inspiration for cardiovascular doctors and jointly promote the continuous progress of cardiovascular surgery in China.
Objective To assess the feasibility, safety, and validity of the TC-Dynamic posterior stabilized prosthesis implanted in the total knee arthroplasty (TKA). Methods Twelve knees of 10 patients (the TC-Dynamic group) were followed up, who had been implanted with the TC-Dynamic posterior stabilized prosthesis from September 2003 to March 2004. Preoperative KSS knee scores were 16.08±11.58, function scores 13.75±19.79, and the range of motion (ROM) of the knee 75.00±26.46°. Meanwhile, 50 knees of 30 patients (the Scorpio group) werefollowed up, who had undergone TKA with the Scorpio posterior stabilized prosthesis.Preoperative KSS knee scores were 19.48±967, function scores 3.16±19.82,andthe ROM of the knee 80.80±22.82°. The anteroposterior and lateral X-ray filmsof each knee were examined before and after operation. The statistical Z-test was used to analyze the differences between the 2 groups in the improvement of the KSS knee scores, function scores, and ROM after operation. Results The average of the 130 days’ follow-up revealed that the patients implanted with the TC-Dynamic prosthesis had an excellent result. In the TC-Dynamic group, the KSS knee scores were 88.83±4.04 with improved scores of 72.75±14.47 compared with those before operation; function scores were 79.17±5.15 with improved scores of 65.42±19.47; the ROM of the knee was 107.92±11.57° with increased degrees of 32.92±32.22°.Meanwhile, in the Scorpio group, the KSS knee scores were 85.68±7.36 with improved scores of 66.20±10.44 compared with those before operation; function scores were 71.40±12.70 with improved scores of 68.24±25.35; the ROM of the knee was 109.20±11.13° withincreaseddegrees of 28.40±26.41°.There was no significant difference in the improvement of the KSS knee scores, function scores, and ROM after operation between the 2 groups （Pgt;0.01）. All the X-ray films of the knees implanted with both the Scorpio prosthesis and the TC-Dynamic prosthesis were analyzed.No malalignment or lucent line with the prosthesis was seen in all these X-ray films. Conclusion The short-term follow-up indicates that the patients implanted with the TC-Dynamic prosthesis have an excellent result. The TC-Dynamic prosthesis with a scientific and proper design is more suitable for the Chinese. However, the long-term outcome of the patients implanted with the TC-Dynamic prosthesis should be observed in a larger number of TKA operations. The basic surgical principles, including excision of both the cruciate ligaments and correction of thebone deformity with the proper balancing of the soft tissues in flexion and extension, are still crucial to successful TKA and to the longterm high survivalrate of the knee prosthesis.
Although metal blocks have been widely used for reconstructing uncontained tibial bone defects, the influence of their elastic modulus on the stability of tibial prosthesis fixation remains unclear. Based on this, a finite element model incorporating constrained condylar knee (CCK) prosthesis, tibia, and metal block was established. Considering the influence of the post-restraint structure of the prosthesis, the effects of variations in the elastic modulus of the block on the von Mises stress distribution in the tibia and the block, as well as on the micromotion at the bone-prosthesis fixation interface, were investigated. Results demonstrated that collision between the insert post and femoral prosthesis during tibial internal rotation increased tibial von Mises stress, significantly influencing the prediction of block elastic modulus variation. A decrease in the elastic modulus of the metal block resulted in increased von Mises stress in the proximal tibia, significantly reduced von Mises stress in the distal tibia, decreased von Mises stress of the block, and increased micromotion at the bone-prosthesis fixation interface. When the elastic modulus of the metal block fell below that of bone cement, inadequate block support substantially increased the risk of stress shielding in the distal tibia and fixation interface loosening. Therefore, this study recommends that biomechanical investigations of CCK prostheses must consider the post-constraint effect, and the elastic modulus of metal blocks for bone reconstruction should not be lower than 3 600 MPa.
The aim of the present experimental study is to determine the effects of sinotubular junction diameter on artificial bioprosthesis valves. An experimental study was performed for aortic root models with different sinotubular junction taper under pulsatile flow condition. The sinotubular junction diameters were modified to create four models with different sinotubular junction tapers with 0, 1, 3 and 5 degrees, respectively, using three dimensional printing techniques. After installing the testing bioprosthesis valve on the aortic root models, we conducted experiments of the pulsatile flow testing with different stroke volume in the pulsatile circulation simulation system. The testing condition was set at the pulse frequency of 70 beats/min and the stroke volume of 2–7 L/min. The status of the valves in 10 continuous pulse cycles was tested and the average results were obtained for each stroke volume. The results of testing showed that the mean transvalvular pressure gradients agreed well with the national standard, and all smaller than 10 mm Hg. The sinotubular junction taper had an influence on regurgitation fraction of the artificial bioprosthesis valve. The smaller sinotubular junction taper showed beneficial effect to decrease the regurgitation fraction. In the case of smaller stroke volume, the smaller sinotubular junction taper was beneficial to increase the effective valve orifice area. In the case of larger stroke volume, the larger sinotubular junction taper was beneficial to increase the effective valve orifice area. This study indicates that a doctor should consider the smaller sinotubular junction taper in the case of smaller stroke volume more. In the case of larger stroke volume, the doctor should consider the larger sinotubular junction taper more.
Objective To review the research of the artificial tracheal prosthesis in the past decade so as to provide theoretical references for the development of the artificial tracheal prosthesis. Methods The l iterature about the artificial tracheal prosthesis was extensively reviewed and analyzed. Results Many new materials are used for the research of artificialtracheal prosthesis which have excellent biocompatibil ity and stabil ity of the structural characteristics. And many compl ications such as migration, obstruction, and infection have been resolved, but so far none of the new materials has been used for cl inical treatment successfully. Conclusion The choice of the materials for artificial tracheal prosthesis is the key to succeed. Biodegradable polymer materials with its unique biological properties become the new direction of the tracheal prosthesis research.
Objective To discuss the clinical application of preserving femoral neck in total hip arthroplasty and to analyze the early stage results.Methods From January 1999 to June 2001, 12 patients underwent total hip arthroplasty with preservation of femoral neck. We cut off the femoral head in infra-head position with improved Moore micro-incisions to reserve intact neck of femur. Thensuitable size of extra cup was selected and placed at 55° eversion angle. The internal cup, made from ultra high polymer poly thene and with ultra radius design, was placed at 45°eversion angle. Harris scores were recorded before operation, after operation and during the follow-up. During the follow-up, the X-rayfilms were taken to assess position, loosening of the prosthesis and ectopic ossification.Results All 12 patients were followed up 2-4.5years with an average of 3.1 years. The mean Harris score of hip elevated from 54 scores before operation to 92 scores of the last follow-up. Mild ectopic ossification occurred in 3 cases. There was no prosthesis loosening and femoral prosthesis setting, and only onepatient had mild bone absorption around femoral prosthesis.Conclusion Total hip arthroplasty with femoral neck preservation is a good option for the patients who need total hip arthroplasty for variable reasons, which is indicated for the patients whose femoral neck is intact with no osteoporosis.
This paper is to report our study in which the differences between prosthetic restoration and surgical reconstruction using traditional clasp retention technology were analyzed based on three-dimensional finite element methods in our laboratory. Firstly, the maxillary unilateral defect model was developed using medical image processing software MIMICS. Secondly, the prosthesis was generated by mirroring technology. The clasp was designed according to the methods raised by Aramany. Then, the stress distribution of maxilla was calculated by simulating occlusion. According to the results, after osseointegration of surgical reconstruction, stresses of unaffected abutments were reduced significantly, and less stress of junction occurred near zygoma of affected side, which were all less than stresses of prosthesis restoration. Thus, removing the clasp of surgical reconstruction increased the stresses of unaffected abutments. The stress trends of maxillary components were different between prosthetic restoration and surgical reconstruction. Surgical reconstruction is better than prosthesis restoration in protection of the abutments. Clasp can alleviate the occlusal burden of maxilla. Varieties of retentive technologies can be considered in prosthesis restoration. The surgical reconstruction is more conducive to rehabilitate unilateral maxilla biomechanically in clinic.