Institute for Building Construction and Technology E-206-4, Vienna University of Technology, Karlsplatz 13, 1040 Vienna, Austria.
Department of Paediatric Orthopaedics, Medical University of Graz, Auenbruggerplatz 34, 8036 Graz, Austria.
Mater Sci Eng C Mater Biol Appl. 2012 Aug 1;32(6):1503-10. doi: 10.1016/j.msec.2012.04.032. Epub 2012 Apr 26.
In this study various biodegradable materials were tested for their suitability for use in osteosynthesis implants, in particular as elastically stable intramedullary nails for fracture treatment in paediatric orthopaedics. The materials investigated comprise polyhydroxybutyrate (PHB), which belongs to the polyester family and is produced by microorganisms, with additions of ZrO2 and a bone graft substitute; two crystalline magnesium alloys with significantly different degradation rates ZX50 (MgZnCa, fast) and WZ21 (MgYZnCa, slow); and MgZnCa bulk metallic glasses (BMG). Push-out tests were conducted after various implantation times in rat femur meta-diaphysis to evaluate the shear forces between the implant material and the bone. The most promising materials are WZ21 and BMG, which exhibit high shear forces and push-out energies. The degradation rate of ZX50 is too fast and thus the alloy does not maintain its mechanical stability long enough during the fracture-healing period. PHB exhibits insufficient mechanical properties: it degrades very slowly and the respective low shear forces and push-out energy levels are unsatisfactory.
在这项研究中，各种可生物降解材料被测试其是否适合用于骨内固定植入物，特别是作为弹性稳定的髓内钉用于儿科矫形骨折治疗。研究的材料包括聚羟基丁酸酯（PHB），它属于聚酯家族，由微生物产生，并添加了 ZrO2 和骨移植替代物；两种具有显著不同降解率的晶态镁合金 ZX50（MgZnCa，快速）和 WZ21（MgYZnCa，缓慢）；以及 MgZnCa 块状金属玻璃（BMG）。在大鼠股骨骨干进行了不同植入时间的推出试验，以评估植入物材料与骨骼之间的剪切力。最有前途的材料是 WZ21 和 BMG，它们表现出高的剪切力和推出能量。ZX50 的降解速度太快，因此在骨折愈合期间，合金不能保持足够的机械稳定性。PHB 表现出不足的机械性能：它降解非常缓慢，相应的低剪切力和推出能量水平令人不满意。
