COMPLIANT POLYMER LUMBAR ARTIFICIAL DISC (PILOT STUDY)

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 脊椎疾病是当今社会最常见、最昂贵的疾病之一。仅在美国，每年就有300亿美元用于腰痛的外科治疗。每年大约有40万例这样的手术。直到最近，“黄金标准”一直是进行脊柱融合术。2005年，FDA首次批准了一种可以在美国免费销售的机械椎间盘替代装置(预计2006年还会有更多的装置)。 然而，专家们担心，与传统的脊柱融合术相比，机械椎间盘置换设备没有希望的(并得到称赞的)长期优势。相邻节段退变，已知是融合的结果，仍然可能作为椎间盘置换手术的不良后果而持续存在。此外，新的并发症，如椎体之间引导不良的运动导致疼痛或来自种植体表面的微小磨损颗粒导致炎症，最终种植体松动，可能会困扰患者。一种新的人工椎间盘概念，即所谓的“顺应性椎间盘”，可能不会有上述缺点，应在狒狒实验中对其临床适用性进行测试。 CADisc植入物由三种不同硬度的聚碳酸酯聚氨酯配方组成，分别用于环、核和终板。端板上有一层薄薄的磷酸钙涂层。该系列制剂和涂层已进行了细胞毒性测试，并已用于12周的绵羊股骨研究的植入物，没有不良反应。此外，聚碳酸酯聚氨酯是一类广为人知的材料，在医疗器械方面有着相当长的历史。它们是首批因其生物稳定性而被推广的聚氨酯材料之一。它们是热塑性弹性体，与碳氢基相邻，具有碳酸酯连接，使这类材料具有氧化稳定性，使这些聚合物对氧化是潜在降解模式的医疗器械应用具有吸引力。此外，聚碳酸酯聚氨酯已被证明可以最大限度地减少表面降解，如应力引起的微裂缝。作为批准的医疗应用的一部分，三种商用等级的聚碳酸酯氨酯正在使用，包括 Bionate‘(聚合物技术集团)、CarbotaneB(Noveon)和ChronoFlexB C(心脏科技国际)。 如果CADisc植入物被证明是目前使用的以金属对金属或金属对聚乙烯表面滑动为特征的人工椎间盘植入物的有效选择，则与这些类型的植入物相关的并发症或不良后果(导致邻近节段退变、突然和疼痛的脊柱运动发作称为“临床不稳”、缺乏轴向缓冲、小磨损颗粒引起炎症等)被证明是有效的。是可以避免的。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Spine ailments are amongst the most common and costly illnesses of today's societies. In the US alone, 30 billion dollars are spent annually for the surgical treatment of low back pain. About 400,000 such surgeries are performed every year. Until recently the 'gold standard' has been to perform a spine fusion. In 2005 FDA cleared for the first time a mechanical disc replacement device to be freely sold in the US (several more devices are expected in 2006). Mechanical disc replacement devices, however, are feared by experts not to have the hoped (and praised) long term advantages when compared to traditional spinal fusion. Adjacent level degeneration, known to exist as a result of fusion, may still persist as an adverse outcome of disc replacement surgery. In addition, new complications such as poorly guided movements between vertebral bodies causing pain or small wear particles originating from the implant surfaces causing inflammation and ultimately implant loosening may plague the patient. A new artificial disc concept, a so-called "compliant disc", that would potentially not have the above shortcomings, shall be tested in a baboon experiment for its clinical suitability. The CAdisc implant is comprised of three polycarbonate polyurethane formulations of different hardness for annulus, nucleus and end plate. The end plates have a thin coating of calcium phosphate. The range of formulations and the coating have been subjected to cytotoxicity testing and have also been used in implants for a 12 week ovine femur study without ill effect. Moreover, polycarbonate polyurethanes are a well understood class of materials, with considerable history in medical devices. They were one of the first classes of polyurethane materials promoted for their biostability. They are thermoplastic elastomers with carbonate linkages adjacent to hydrocarbon groups which give this class of materials oxidative stability, making these polymers attractive for medical device applications where oxidation is a potential mode ofdegradation. In addition, polycarbonate polyurethanes have been shown to minimize surface degradation such as stress induced microfissures. Three commercial grades of polycarbonate urethanes are in use as part of approved medical applications, including Bionate' (the Polymer Technology Group), CarbothaneB (Noveon) and ChronoFlexB C (CardioTech International). Should the CAdisc implant prove to be a valid option to presently used artificial disc implants featuring sliding metal-on-metal or metal-on-polyethylene surfaces, complications or adverse outcomes associated with these types of implant (induced adjacent level degeneration, sudden and painful giveaway episodes for spinal movements known as "clinical instability," lack of axial cushioning, small wear particles causing inflammation, etc.) could be avoided.