Summary of Background Data.Recommended threshold criteria for solid fusion using flexion-extension radiographs hae aried from 0[degrees] to 5[degrees] of angular motion between ertebrae.

• 概括背景资料：我们推荐评判融合是否稳定的标准是：在腰椎过伸过屈位片上，椎间的矢状面活动角度不超过5度。