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BACKGROUND:Lumbar fusion surgery as an important and effective means of treating degenerative diseases is widely used in clinical application for almost a century. However, long-term clinical evidence showed that lumbar fusion also brought some problems, such as the loss of waist flexibility, complications of donor site, fusion segment motion loss and accelerating the adjacent segment degeneration. In recent years, the theory of spinal dynamic stabilization had spread widely, and a variety of non-fusion surgery is becoming more broadly used in treatment of lumbar degenerative disease. OBJECTIVE:To review the application of non-fusion surgery in the treatment of lumbar degenerative diseases and explain application perspectives and experiences. METHODS:Databases including PubMed and CNKI were retrieved to col ect clinical application and views about non-fusion internal fixation in the treatment of lumbar degenerative diseases from 2007 to 2016. The key words were“lumbar, non-fusion, bone fusion, dynamic stabilization, adjacent segment degeneration”. RESULTS AND CONCLUSION:Thirty papers were included in the final analysis after screening by two independent researchers. We summarized the lumbar non-fusion technology, including artificial nucleus replacement, total disc replacement and posterior lumbar dynamic stabilization device. The philosophy of these new technologies is to provide stability and physiological activity, reducing the abnormal stress that leads to adjacent segment degeneration. These methods can be applied to the step of treatment of lumbar degenerative diseases and to reduce the fusion of diseased segments. Simultaneously, it is needed to strictly grasp the indications for surgery, to identify the cause of the pain caused by low back pain and lumbar spine instability, and to select the most suitable non-fusion device for individual treatment.
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BACKGROUND:cells under mechanical stimulation can achieve their biological functions by converting mechanical signals into chemical signals through certain signal transduction mechanism. As the fibrous framework throughout a cell, cytoskeleton is one of the critical components in this process. OBJECTIVE:Through systemical y analyzing the role of the cytoskeleton in mechanical signal transduction, to provide a potential therapeutic target for the clinical treatment of cytoskeleton related diseases. METHODS:In order to search relevant articles about the mechanics mechanism of signal transduction of cytoskeleton from PubMed and CNKI databases (from 1990 to 2012), a computer-based search was performed, using the key words of“cytoskeleton, microtubules, microfilaments, intermediate filaments, mechanical stimulation, signal transduction”in English and Chinese, respectively. After eliminating literatures which were irrelevant to research purpose or containing a similar content, 48 articles were chosen for further analysis. RESULTS AND CONCLUSION:Mechanical stimulation plays an important role in cellproliferation, development and apoptosis. With the gradual understanding of the biological function of cytoskeleton, people have found that cytoskeleton is one of the critical components in the process of the mechanical signal transduction. After getting mechanical stimulation, cytoskeleton can be reorganized through Rho, protein kinase C, integrin and mitogen-activated protein kinase signaling pathways, then converting the mechanical stimulation to chemical signals and finishing its biological functions final y.
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BACKGROUND: Orthopedic academics are committed to the modification of calcium phosphate cement (CPC) by adding different additives, including the promotion of curing agents, plasticizers, anti-water blood solvent, porogen, enhancer, or biological activity substance or drug compound to the CPC in order to enhance its physical and chemical and biological properties which is a research hotspot in the field. OBJECTIVE: To investigate the physical and chemical characteristics of a biodegradable injectable CPC. DESIGN, TIME AND SETTING: Duplicated testing study was performed at the National Key Laboratory, College of Materials, South China University of Technology from December 2008 to May 2009. MATERIALS: Calcium phosphate with partial crystallization and strontium phosphate and calcium hydrogen phosphate dehydrate with partial crystallization were added with modified starch and type I collagen to prepare a new type of self-injectable CPC. METHODS: CPC phase was analyzed using X'Pert Pro X-ray diffractometer; CPC morphology was observed using HITA2 -CHIH-800 transmission/scanning electron microscope; setting-up time was tested using Vicat apparatus according to A S TM C190203 standard; compressive strength was measured using Instron 5567 omnipotent electron apparatus; syringeability was detected using syringe apparatus with 1.6 mm of inside diameter; collapsibility was tested using soaking-shaking quantitative materials. MAIN OUTCOME MEASURES: Phase component and microstructure of CPC products, setting-up time, syringeability, compressive strength, and collapsibility. RESULTS: The material coul be injected with an excellent performance, and the modified starch significantly improved the resistance of bone cement collapsibility. As the bone cement liquid-solid ratio increased, the compressive strength of cement decreased. When the bone cement liquid-solid ratio was 0.3, the compressive strength for cement was (48.0±2.3) MPa when the bone cement liquid-solid ratio was 0.6, the compressive strength of bone cement reduced to (21,0±2.5) MPa. Hydration productof cement-like bone hydroxyapatite crystallization also could be seen from the X-ray diffraction, due to the hydration of-cement was not complete, a baseline level of volatile explained fully hydrated conditions, suggesting that the bone cement could farther improve the compression strength. CONCLUSION: Developed an injectable strontium-contained collagen CPC is coincidence with the biomechanical strength of the human body and meets the requirements of the operation conditions.
ABSTRACT
The injectable calcium phosphate material is present to solve the clinical bone defects of bone tissue and the potential to undermine the ideal substitute. But the properties and biological evaluation are still to be improved. Therefore,the material of the academic community and the academic orthopedic bone cement was modified for a variety of studies,and the addition of strontium bone cement significantly improved the performance. The article indicated strontium-mixed calcium phosphate bone cement was characterizing by the compressive strength,the degradability,the hardening time,the solubility,the injection and the anti-water-solubility,suggesting the clinical practice of the strontium-mixed calcium phosphate bone cement. Prospectively,the strontium-mixed calcium phosphate bone cement may take in the bone tissue repair domain as a artificial bone substitution material.
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[Objective]To discuss a reasonable treatment for unstable intertrochanteric hip fractures in senile patients by comparing the effects of PFN fixation and hemiarthroplasty.[Method]Totally 82 intertrochanteric hip fractures in senile patients with complete clinical data were retrospectively analyzed,who were treated with hemiarthroplasty or PFN fixation from April 2005 to April 2007.Forty-six were treated with hemiarthroplasty,36 were treated with PFN fixation.All of them had multiple medical co-morbidities.According to modified Evens-Jensen classification,all of them belonged to unstable fracture.Comparison was made between the two treated groups in terms of the length of incision,operative time,the blood lost,blood transfusion during or after surgery,time for bed rest postoperatively,postoperative complications and St.Michael hip score one year after surgery.[Result]The average duration of follow-up for PFN fixation and hemiarthroplasty were 16 and 18 months respectively.Compared with the group of hemiarthroplasty,the group of PFN fixation experienced longer operation time,longer time for bed rest postoperatively,less blood lost,less blood transfusion during or after surgery,shorter incision length,and the differences between two groups had statistical significance (P0.05).[Conclusion]Both of the two methods are reasonable treatment for unstable intertrochanteric hip fractures in senile patients.