Teo Alex Quok An, Ng David Qing Kai, Ramruttun Amit Kumarsing, O'Neill Gavin Kane
Department of Orthopaedic Surgery, National University Hospital Singapore, 1E Kent Ridge Road, NUHS Tower Block Level 11, Singapore 119228.
Centre for Additive Manufacturing, National University of Singapore, 3 Research Link, #05-01, Innovation 4.0 Building, Singapore 117602.
Injury. 2022 Feb;53(2):676-682. doi: 10.1016/j.injury.2021.11.051. Epub 2021 Nov 25.
3D-printed implants could improve the capture of fracture fragments for improved stability of tibial plateau fracture fixation. The aim of this study was to compare the biomechanical strength of fixation constructs using standard and customised 3D-printed proximal tibial locking plates for fixation of tibial plateau fractures.
This is a biomechanical study utilising six pairs of cadaveric tibiae. Fractures were created in an identical fashion using an osteotome and mallet, and fixed using either a standard, commercially-available proximal tibia locking plate or a customised 3D-printed plate. Design and production of the customised plates followed a "3D printing at point-of-care" model. Customised stainless steel 316 L plates were produced within a local additive manufacturing laboratory based upon pre-operative CT scans. Determination of implant choice within each cadaver pair was performed via simple randomisation. Following fracture fixation, the tibiae were skeletalised and biomechanically tested using a customised loading jig and a size-matched femoral knee prosthesis. The constructs were loaded cyclically from 100 N to approximately three times the cadaveric body-weight at 5 Hz for 10 000 cycles. Every 1000 cycles, the test was paused and the tibia was physically checked for failure. If failure had not occurred by the end of the testing cycle, the construct was loaded to failure and the load at which the construct failed was noted.
Fixation constructs using the 3D-printed plates performed comparably to those using the standard plates. There was no significant difference in the degree of fracture fragment displacement in both constructs. Overall longitudinal construct stiffness and load to failure was higher in the 3D-plates group but this did not reach statistical significance.
Production of customised plates for proximal tibia fractures at point-of-care is feasible, however fixation constructs with these plates did not provide any biomechanical advantage over standard plates in terms of axial loading stiffness.
3D打印植入物可改善骨折碎片的固定，从而提高胫骨平台骨折固定的稳定性。本研究旨在比较使用标准和定制3D打印胫骨近端锁定钢板固定胫骨平台骨折时固定结构的生物力学强度。
这是一项生物力学研究，使用了六对尸体胫骨。使用骨凿和槌以相同方式制造骨折，并用标准的市售胫骨近端锁定钢板或定制的3D打印钢板进行固定。定制钢板的设计和生产遵循“即时3D打印”模式。基于术前CT扫描在当地的增材制造实验室生产定制的不锈钢316L钢板。通过简单随机化确定每对尸体中植入物的选择。骨折固定后，将胫骨骨骼化，并使用定制的加载夹具和尺寸匹配的股骨膝关节假体进行生物力学测试。将结构从100N开始以5Hz的频率循环加载至尸体体重的约三倍，持续10000个循环。每1000个循环暂停测试，对胫骨进行物理检查以确定是否失效。如果在测试周期结束时未发生失效，则将结构加载至失效，并记录结构失效时的载荷。
使用3D打印钢板的固定结构与使用标准钢板的固定结构表现相当。两种结构中骨折碎片的位移程度没有显著差异。3D打印钢板组的整体纵向结构刚度和失效载荷更高，但未达到统计学意义。
即时生产定制的胫骨近端骨折钢板是可行的，然而就轴向加载刚度而言，使用这些钢板的固定结构并未比标准钢板提供任何生物力学优势。
