Degenerative disc disease (DDD) is the leading cause of low back pain and radiating leg pain. DDD is commonly treated surgically using spinal fusion techniques, but in many cases failure occurs due to insufficient immobilization of the vertebrae during fusion. The fabrication and demonstration of a 3D-printed semi-crystalline liquid crystal elastomer (LCE) spinal fusion cage that addresses these challenges in particular subsidence are described. During implantation of the fusion cage, the LCE is rubbery and capable of deforming around and conforming to delicate anatomy. In the hours following implantation, the device crystallizes into a rigid, structural material with the modulus increasing tenfold from 8 to 80 MPa. In the crystalline regime, a 3D-printed prototype device is capable of enduring 1 million cycles of physiologic compressive loading with minimal creep-induced ratcheting. Effects of LCE molecular architecture on the rate and magnitude of modulus increase, material processability, and mechanical properties are explored. This fundamental characterization informs a proof-of-concept device-the first bulk 3D printed LCE demonstrated to date. Moreover, the novel deployment strategy represents an exciting new paradigm of spinal fusion cages, which addresses real clinical challenges in expandable interbody fusion cages.

中文翻译：

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动态结晶液晶弹性体，用于可扩展的符合终板的椎间融合器笼。

椎间盘退变性疾病（DDD）是下腰痛和辐射性腿痛的主要原因。DDD通常通过脊柱融合术进行手术治疗，但是在许多情况下，由于融合过程中椎骨固定不足而导致失败。描述并解决了这些挑战的3D打印半结晶液晶弹性体（LCE）脊柱融合器的制造和演示。在融合笼植入过程中，LCE呈橡胶状，能够在周围变形并符合精致的解剖结构。在植入后的几个小时内，该装置结晶为刚性的结构材料，其模量从8 MPa增加到80 MPa十倍。在结晶状态下 3D打印的原型设备能够承受100万次生理压缩负荷循环，并且蠕变引起的棘齿最小。研究了LCE分子结构对模量增加的速率和幅度，材料可加工性以及机械性能的影响。这一基本特征为概念验证设备提供了有力的证明，这是迄今为止首次展示的批量3D打印LCE。此外，新颖的部署策略代表了脊柱融合器的令人兴奋的新范例，它解决了可扩展的椎间融合器中的实际临床挑战。这一基本特征为概念验证设备提供了信息，这是迄今为止首次展示的批量3D打印LCE。此外，新颖的部署策略代表了脊椎融合器的激动人心的新范例，它解决了可扩展的椎间融合器中的实际临床挑战。这一基本特征为概念验证设备提供了信息，这是迄今为止首次展示的批量3D打印LCE。此外，新颖的部署策略代表了脊柱融合器的令人兴奋的新范例，它解决了可扩展的椎间融合器中的实际临床挑战。