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

Figure 4

Pathoanatomic risk factors for ASD in lumbar spine are (a) facet sagittalization < 52.7°, (b) laminar horizontalization > 130°, and (c) facet tropism (more than 10° divergence of both facet joints).

(a)

(b)

(c)