Longitudinal change of cervical artificial disc motion following replacement

Even though implanted segment
maintains its motion for some length of time, we could assume that an artificial disc
would have limited life expectancy correlated with decline of extension angle.

即便植入节段能够在一定时长内维持其运动状态，我们亦可推定，人工椎间盘（artificial disc）的预期寿命有限，且该寿命与伸展角度的衰减存在关联。