Abstract:Objective Design a new kind of titanium alloy artificial lumbar intervertebral disc and evaluate its biomechanical features.Methods The new designed artificial lumbar intervertebral disc with ball and socket joint was made of new titanium alloy with low stiffness(50GPa).The tests for compressive stiffness,torsional stiffness and fatigue strength of the artificial disc were made by the material testing machine.Results The new artificial lumbar intervertebral disc has had the functions for flexion,extension,lateral bending when tested with the mechanical tests to show its compressive stiffness as 50~66.7GPa,which is 1/3 of stainless steel.And its torsion stiffness is 388.54Nm/°.No obvious damage appeared after 1 07 fatigue strength tests.Compared with the stiffness before testing,it showed that 1,2,5 and 10 million cycles made no significant difference.Conclusion The new artificial lumbar intervertebral disc showed similar mechanical characteristics to that of the normal human lumbar disc.