Development status of medical titanium alloy for fracture fixation

Pure titanium was first applied in orthopedics as internal fixation plate and screw in 1965. It has high corrosion resistance, good biocompatibility and high safety, and will not cause tissue adverse reactions. Titanium plate has a low elastic modulus (68 GPa), which can significantly reduce the stress shielding effect during fracture healing. It is an ideal material for making bone plates and screws. However, the poor ductility of titanium leads to the difficulty of machining, and the tensile strength of titanium plate is also limited.

At present, Ti6Al4V, Ti6Al7Nb, Ti13Nb13Zr, Ti15Zr4Nb4Ta2Pd and Ti29Nb13Ta46Zr alloys have been studied and widely used in clinical practice. Satisfactory experimental results and reliable clinical evidence have been obtained. Titanium alloy Ti2448 was independently developed by Shenyang Institute of Metal Research, Chinese Academy of Sciences. Its elastic modulus is only 42 GPa, which has been proved to be effective in avoiding stress shielding effect and promoting fracture healing in relevant experiments. The high strength and low elastic modulus of titanium alloy make it more suitable for fracture fixation, but the poor ductility and fatigue resistance of titanium alloy, and the lack of bone tissue induction, further restrict the application of titanium alloy.