Vanaclocha Amparo, Vanaclocha Vicente, Atienza Carlos M, Jorda-Gomez Pablo, Diaz-Jimenez Cristina, Garcia-Lorente Jose A, Saiz-Sapena Nieves, Vanaclocha Leyre
Escuela de Doctorado, Universitat Politècnica de Valencia, Camí de Vera, s/n, 46022, Valencia, Spain.
University of Valencia, Avenida de Blasco Ibáñez, 15, 46010 Valencia, Spain.
Heliyon. 2023 Feb 4;9(2):e13540. doi: 10.1016/j.heliyon.2023.e13540. eCollection 2023 Feb.
The intact intervertebral disc is a six-freedom degree elastic deformation structure with shock absorption. "Ball-and-socket" TDR do not reproduce these properties inducing zygapophyseal joint overload. Elastomeric TDRs reproduce better normal disc kinematics, but repeated core deformation causes its degeneration. We aimed to create a new TDR (ADDISC) reproducing healthy disc features. We designed TDR, analyzed (Finite Element Analysis), and measured every 500,000 cycles for 10 million cycles of the flexion-extension, lateral bending, and axial rotation cyclic compression bench-testing. In the inlay case, we weighted it and measured its deformation. ADDISC has two semi-spherical articular surfaces, one rotation centre for flexion, another for extension, the third for lateral bending, and a polycarbonate urethane inlay providing shock absorption. The first contact is between PCU and metal surfaces. There is no metal-metal contact up to 2000 N, and CoCr28Mo6 absorbs the load. After 10 million cycles at 1.2-2.0 kN loads, wear 140.96 mg (35.50 mm), but no implant failures. Our TDR has a physiological motion range due to its articular surfaces' shape and the PCU inlay bumpers, minimizing the facet joint overload. ADDISC mimics healthy disc biomechanics and Instantaneous Rotation Center, absorbs shock, reduces wear, and has excellent long-term endurance.
完整的椎间盘是一种具有六个自由度且能减震的弹性变形结构。“球窝”式人工椎间盘置换术（TDR）无法重现这些特性，会导致关节突关节过载。弹性体TDR能更好地重现正常椎间盘的运动学，但反复的核心变形会导致其退变。我们旨在研发一种能重现健康椎间盘特征的新型TDR（ADDISC）。我们设计了TDR，进行了分析（有限元分析），并在屈伸、侧弯和轴向旋转循环压缩台架试验中，每50万次循环进行测量，直至1000万次循环。对于镶嵌件，我们对其称重并测量其变形。ADDISC有两个半球形关节面，一个用于屈伸的旋转中心，另一个用于伸展，第三个用于侧弯，还有一个聚碳酸酯聚氨酯镶嵌件用于减震。首次接触发生在PCU和金属表面之间。在2000N以下没有金属与金属的接触，CoCr28Mo6能吸收载荷。在1.2 - 2.0kN载荷下进行1000万次循环后，磨损140.96mg（35.50mm），但没有植入物失效。我们的TDR因其关节面形状和PCU镶嵌件缓冲器而具有生理运动范围，可将小关节过载降至最低。ADDISC模仿健康椎间盘的生物力学和瞬时旋转中心，能吸收冲击、减少磨损，并具有出色的长期耐久性。
