Pathoanatomic Risk Factors for Instability and Adjacent Segment Disease in Lumbar Spine: How to Use Topping Off?

Figure 6

CT-scan of patient in Figure 5 with posterior lumbar interbody fusion in L5/S1 and ASD in L4/5. (a) Axial slice with facet tropism (17°) and (b) sagittal slice with laminar horizontalization of 141,5°.

(a)

(b)