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find Keyword "Artificial" 228 results
  • EXPERIMENTAL STUDY ON TENSILE STRENGTH OF CARBONTENDON IMPLANTEDINTO BONE

    A mechanical study on the bones of 29 rabbits following implantation of carbontendon was carried out. The rabbits were divided into seven groups according to the observation time (2,4,6,8,12,20 and 30 weeks after operation). A bundle of artificial tendon composed of 7,000 carbon fibers was passedthrough a tunnel in the tibia, and both ends of the artificial tendon were ligated to the muscle fibers. The mechanical strength and histological structure of the carbonbone junction and their relationship were studied in each group. Carbon fiberwas split and degradated in six to eight weeks after operation. The tensile strength of carbontendon in the soft tissue was decreased from 82±4.6N in the second week to 27±5.31N and6.3±1.81N in the sixth and eighth week respectively. The tensile strength of carbontendon increased from 3.01±1.2N to 6.1±2.01N at the carbon -tendon-bone junction in the bone. The tensile strength of carbon-tendon was unsatisfactory for implantation into bone. The carbon-tendon was split and degradated and the tensile strength was not b enough to cope with the early functional exercises.

    Release date:2016-09-01 11:10 Export PDF Favorites Scan
  • INITIATIVE REPORT OF THE HYDROXYAPATITE ORBITAL IMPLANT DRILLING PROCEDURE

    OBJECTIVE: To evaluate the clinical effect of drilling procedure following the hydroxyapatite orbital implantation. METHODS: From February 1996 to April 2000, 146 consecutive patients who received hydroxyapatite orbital implant were drilled and inserted a motility peg 6 to 16 months after hydroxyapatite implantation. Among them, there were 97 males and 49 females, aged from 18 to 60 years old, of the 146 motility pegs, 36 were sleeved pegs and 110 were nonsleeved. Goldman visual field analyzer was applied to measure the degree of artificial eye’s movement before and after drilling. RESULTS: Followed up for 1 to 40 months, no secondary infection occurred. The mobility of the prosthesis increased from (18.7 +/- 3.8) degrees preoperatively to (42.3 +/- 3.7) degrees postoperatively. CONCLUSION: The delayed drilling procedure and motility peg insertion improve the range of movement and the sensitivity of the artificial eye with a low rate of complications.

    Release date:2016-09-01 10:21 Export PDF Favorites Scan
  • CLINICAL APPLICATION AND RELATIVE EXAMINATION OF MORSELIZED BONE

    Objective To review progress of clinical application ofmorselized bone and to investigate relative exploration on it.Methods The recent articles on morselized bone in the field of clinicand experimental research were extensively reviewed, and relative examination of morselized bone referring to method and mechanism were investigated carefully.Results Morselized bone worked well clinically, especially inrevision ofartificial total hip joint, and it was proved effective with lots of advantages.Conclusion Morselized bone functions well clinically. Although its mechanism requires a further research, it still has a promising value in clinical application.

    Release date:2016-09-01 09:33 Export PDF Favorites Scan
  • CELLULAR SOCIOLOGICAL CHARACTERISTICS OF OSTEOBLASTS

    There is a great hope to treat long bone defects with bioactive artificial bone constructed by osteoblasts and biomaterials, in which the key point is to provide an optimum environment for the normal function of osteoblasts. The cellular sociological characteristics of osteoblasts were summarized and it was suggested that the ideal bioactive artificial bone should be composed of inorganic and organic materials together with cellular components such as osteoblasts and vascular endothelial cells, and combined with control release of growth factors, following its implantation it could be vascularized very soon and merged with the host bone by bony consolidation.

    Release date:2016-09-01 11:07 Export PDF Favorites Scan
  • EVALUATION OF FIBULAR HEAD RESECTION IN PROSTHETIC REPLACEMENT FOR NEOPLASMS OF PROXIMAL TIBIA IN LIMB SALVAGE SURGERY

    ObjectiveTo investigate the effects of fibular head resection in prosthetic replacement for neoplasms of the proximal tibia in limb salvage surgery. MethodsBetween July 1999 and March 2013, 76 patients with neoplasms of the proximal tibia underwent tumor resection, prosthetic replacement, and gastrocnemius medial head flap transfer. Among them, 38 patients underwent fibular head resection (group A) and 38 underwent fibular head preservation (group B). There was no significant difference in gender, age, side, tumor classification and stage, and disease duration between 2 groups (P>0.05). The complications and the position of the components were observed, and American society for bone tumors scoring system (MSTS93) was used to evaluate the joint function. ResultsAll patients were followed up 12-150 months (mean, 87 months). Incision infection occurred in 1 patient (2.63%) of group A and 6 patients (15.79%) of group B, showing significant difference (χ2=3.934, P=0.047). Necrosis of gastrocnemius medial head flap was found in 1 patient of group A and 2 patients of group B. Prosthetic loosening and instability of the knee were observed in 4 and 2 cases of group A and in 6 and 4 cases of group B, respectively. In groups A and B, there were 3 and 5 cases of local recurrence, 7 and 6 cases of distant metastasis, and 8 and 7 deaths, respectively. According to MSTS93, the results were excellent in 23 cases, good in 10 cases, fair in 3 cases, and poor in 2 cases, with an excellent and good rate of 86.84% in group A; the results were excellent in 21 cases, good in 11 cases, fair in 3 cases, and poor in 3 cases, with an excellent and good rate of 84.21% in group B; and no significant difference was found in the excellent and good rate between 2 groups (χ2=0.106, P=0.744). ConclusionFibular head resection in prosthetic replacement for neoplasms of the proximal tibia in limb salvage surgery is beneficial to intra-operative tissue coverage, and it can reduce trauma by skin transplantation and related complications. Good stability and motion of the joint can be obtained after operation.

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  • OUTCOMES OF CEMENTLESS TOTAL HIP REPLACEMENT IN TREATMENT OF OSTEOARTHRITIS

    Objective To evaluate the clinical results of cementless total hip replacement (THR) in treating osteoarthritis and identifying the factors affecting the results. Methods From January 1995 to December 1999, 76 patients(85 hips) with osteoarthritis of hip joint were treated. These patients were assessed according to Harris hip score and X-ray film. The average follow-up time was 49.3 months. Results The average Harris score in the patients was 90.9 points. The excellent or good rate was 91.9%(75/85). Pain in the thigh existed in 23 hips (27.5%). The femoral osteolysis occurred in 14 hips(16.5%). The radiographical result demonstrated femoral loosening in 2 hips. harris score became lower when the femoral component of osteoarthritis of hip jointl. Pain in the thigh may be related to the varus placement of femoral component and femoral osteolysis. Femorla osteolysis is one of important factors affectin the long-term outcomes.

    Release date:2016-09-01 09:35 Export PDF Favorites Scan
  • INHIBITION OF ASEPTIC LOOSENING BY RECEPTOR ACTIVATOR OF NUCLEAR FACTOR KAPPA B LIGAND ANTIBODY IN OSTEOLYSIS MODEL OF MOUSE

    Objective Aseptic loosening of prosthesis is associated with peri prosthetical osteolysis caused by osteoclast activation. Receptor activator of nuclear factor kappa B (NF-κB) l igand (RANKL)/receptor activator of NF-κB (RANK) signalpathway is fundamental in osteoclast activation. To determine whether RANKL antibody can inhibit inflammatory osteolysis in a osteolysis model of mouse. Methods Sixty female BALB/c mice (aged 8-10 weeks, weighing 18-20 g) were selected. The skull bone piece was harvested from 20 mice as the donor of bone graft; the subcutaneous air pouches (2 cm × 2 cm) models were established on the back of the other 40 mice and the skull bone piece was inserted into the air pouches. The 40 mice were equally divided into groups A (negative control group), B (positive control group), C (low-dose RANKL antibody group), and D (high-dose RANKL antibody group). At 1 day after bone graft, 0.5 mL PBS was injected into the pouch of group A, 0.5 mL PBS containing titanium particle into groups B, C, and D. At 2 days before the titanium particle was injected, RANKL antibody (0.1 mL) were injected into the pouch of group C (50 μg/mL) and group D (500 μg/mL), respectively every day for 2 days, and 0.1 mL PBS into groups A and B. At 14 days after bone implantation, the pouchmembranes containing implanted bone were harvested for gross observation and histological analyse. Results All mice survived to the end of experiment, and incisions healed well. The gross observation showed that inflammatory responses, exudation, and vascular proliferation were obvious in group B, and were inconspicuous in groups A, C, and D. The histological analysis showed that significantly more infiltration of inflammatory cells, more obvious bone resorption, more bone collagen loss, and more positive staining area were observed in group B than in groups A, C, and D. There were significant differences in inflammatory cell number, pouch membrane thickness, bone collagen loss, and osteoclast content between group B and groups A, C, and D (P lt; 0.05). Conclusion RANKL antibody can directly blockRANKL/RANK signal pathway, which is an efficient therapy to inhibit bone absorption associated with implant wearing particles.

    Release date:2016-08-31 05:44 Export PDF Favorites Scan
  • EFFECTIVENESS COMPARISON BETWEEN OPEN REDUCTION COMBINED WITH INTERNAL FIXATION AND ARTIFICIAL RADIAL HEAD REPLACEMENT IN TREATING MASON TYPE-III COMMINUTED FRACTURES OF RADIAL HEAD

    To compare the effectiveness between open reduction combined with internal fixation and artificial radial head replacement in treating Mason type-III comminuted fracture of radial head, to provide the evidence for available treatment methods. Methods Between January 2004 and June 2008, 65 cases of Mason type-III comminuted fractures were treated with open reduction, AO mini plate and screw system or a combination of Kirschner treatment (internal fixation group, n=35) and with artificial radial head replacement (replacement group, n=30). In internal fixation group, there were 21 males and 14 females with an age range of 21 to 35 years (mean, 30.7 years); the causes of injury were traffic accidentin 12 cases, fall ing from height in 8 cases, and a fall in 15 cases; the locations were left side in 23 cases and right side in 12 cases; and the time between injury and surgery was 1-7 days (mean, 3 days). In replacement group, there were 19 males and 11 females with an age range of 23 to 67 years (mean, 32.5 years); the causes of injury were traffic accident in 7 cases, fall ing from height in 8 cases, and a fall in 15 cases; the locations were left side in 17 cases and right side in 13 cases; and the time between injury and surgery was 1-6 days (mean, 1.5 days). There was no significant difference in gender, age, disease cause, disease duration, or other general information between 2 groups (P gt; 0.05), so that 2 series of patients had comparabil ity. Results Incisions healed primarily in 2 groups. All patients were followed up 1 to 4 years with an average of 2.5 years. There were significant differences in elbow flexion angle, extension angle, and forearm rotation angle between 2 groups (P lt; 0.05), but no significant difference in elbow pronation or supination weakness (P gt; 0.05). In internal fixation group, primary union occurred in 29 cases, delayed union in 2 cases, nonunion with ectopic ossification in 2 cases, and internal fixation failure in 2 cases. In replacement group, elbow flexion angle lost beyond 30º in 1 case after 1 year, elbow stiffness occurred in 1 case because prosthesis was too long. According to Broberg and Morrey elbow scores system, the scores were 69.51 ± 10.23 in internal fixation group and 81.55 ± 12.06 in replacement group, showing significant difference (P lt; 0.05). The results were excellent in 15 cases, good in 5 cases, fair in 11 cases, and poor in 4 cases with an excellent and good rate of 57.1% in internal fixation group; the results were excellent in17 cases, good in 5 cases, fair in 6 cases, and poor in 2 cases with an excellent and good rate of 73.3%. Conclusion Artificial radial head replacement can achieve better joint function compared with open reduction combined with internal fixation in treating Mason type-III comminuted fractures of radial head.

    Release date:2016-08-31 05:48 Export PDF Favorites Scan
  • Artificial intelligence in thoracic surgery

    As an emerging technology, artificial intelligence (AI) uses human theory and technology for robots to study, develop, learn and identify human technologies. Thoracic surgeons should be aware of new opportunities that may affect their daily practice by the direct use of AI technology, or indirect use in the relevant medical fields (radiology, pathology, and respiratory medicine). The purpose of this paper is to review the application status and future development of AI associated with thoracic surgery, diagnosis of AI-related lung cancer, prognosis-assisted decision-making programs and robotic surgery. While AI technology has made rapid progress in many areas, the medical industry only accounts for a small part of AI use, and AI technology is gradually becoming widespread in the diagnosis, treatment, rehabilitation, and care of diseases. The future of AI is bright and full of innovative perspectives. The field of thoracic surgery has conducted valuable exploration and practice on AI, and will receive more and more influence and promotion from AI.

    Release date:2021-10-28 04:13 Export PDF Favorites Scan
  • EXPERIMENTAL STUDY OF NOVEL INJECTABLE NUCLEUS PULPOSUS PROSTHESES IMPLANT

    To explore the histological and the hematological change of rabbits after implanting novel injectable artificial nucleus prostheses, and to evaluate the biological safety. Methods In accordance with Biological Evaluation of Medical Devices, materials of polyurethane, sil icone rubber and macromolecular polyethylene for medical use were made into short column 1 cm in length and 0.3 cm in diameter. Forty-eight SPF New Zealand white rabbits weighing 2.5-3.0 kg were used, and cavity 1 cm in depth was made in the area 2 cm away from the spinal midl ine by separating muscle.Then according to different material being implanted, the rabbits were divided into 3 groups (n=16): Group A, polyurethane; group B, sil icone rubber; group C, macromolecular polyethylene for medical use as negative control. General condition of the rabbits was observed after operation. Gross and histology observation were conducted 1, 4, 12 and 26 weeks after operation. Blood routine, biochemical function and electrolyte assays were performed 26 weeks after operation to observe pathological changes of organs. Meanwhile, physicochemical properties of the materials were detected, and the material in the same batch was used as negative control. Results All rabbits survived until the end of experiment, and all wounds healed by first intention. In each group, red swollen muscles were observed 1 week after operation and disappeared 4 weeks after operation, connective tissue around the implanted materials occurred 12 and 26 weeks after operation. At 26 weeks after operation, there were no significant differences among three groups in blood routine, biochemical function and electrolyte assays (P gt; 0.05). Organs had smooth surface without ulceration, ecchymosis, obvious swell ing, hyperemia or bleeding, and nodules. There were no significant differences among three groups in percentage weight of each organ (P gt; 0.05). Histology observation: granulation tissue prol iferation and inflammatory cell infiltration were observed in each group 1 week after operation, fibrous capsule formation around the materials and the disappearance of inflammatory cell infiltration were evident 4 weeks after operation, cyst wall grewover time and achieved stabil ity 12 weeks after operation. The inflammatory response and the fiber cyst cavity of groups A and B met the standard of GB/T 16175 and were in l ine with group C. No specific pathological changes were discovered in the organs 26 weeks after operation. For group A, no significant difference was evident between before and after material implantation in terms of weight average molecular weight, number average molecular weight, tensile strength at break and elongation at break (P gt; 0.05). For group B, no significant difference was evident between before and after material implantation in shore hardness (P gt; 0.05). Conclusion Novel injectable nucleus pulposus prostheses do not damage local tissue and function of organs, but provide good biocompatibil ity and biological safety.

    Release date:2016-09-01 09:07 Export PDF Favorites Scan
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