Figure 2
From: Correlation of bone density to screw loosening in dynamic stabilization: an analysis of 176 patients
Post-operative 24 months CT demonstrated bilateral screw loosening at L4 in a 64 year-old male who underwent dynamic stabilization at L3–4 (black arrow: double halo sign), although all HU values of L4 pedicles were much higher than the mean HU values in our cohort. (L4 right pedicle HU including/excluding cortex bone: 350/276; left pedicle HU including/excluding cortex bone: 355/272; VB HU: 117).
