Does undercut macrostructure cage cause increase of subsidence incidence and decrease of disc height?

With great interest, we recently read the article by Walsh et al. in which they found that undercut macrostructures within the interbody cage could significantly improve the fusion and biomechanical stability of the spine [1]. In Figs. 4 and 5, sagittal and coronal μCT images show obvious fusion with continuous bone bridge formation within the undercut macrostructure of the test cage at both 6 and 12 weeks, but no fusion was seen in the control cage group [1]. However, both sagittal and coronal μCT images show a decrease of the disc height at the fused L4– L5 level which may be due to cage subsidence.

Source: The Spine Journal - January 26, 2021 Category: Orthopaedics Authors: Huiliang Yang, Camilo Osorio, Chunguang Zhou Tags: Letters to the editor Source Type: research