Failure of a polyether-ether-ketone expandable interbody cage following transforaminal lumbar interbody fusion

Purpose Expandable cages are a more recent option for maintaining or restoring disc height and segmental lordosis with transforaminal lumbar interbody fusion (TLIF). Complications associated with expandable cages have not yet been widely reported. We report a case of postoperative failure of a polyether-ether-ketone (PEEK) expandable interbody device used during TLIF. Methods A 50-year-old man presented with severe back and right leg pain after undergoing L4-5 and L5-S1 TLIFs with expandable cages and L3-S1 posterior instrumented fusion. Imaging showed retropulsion of a portion of the interbody cage into the spinal canal causing nerve compression. Displacement occurred in a delayed manner. In addition, pseudoarthrosis was present. Results The patient underwent re-exploration with removal of the retropulsed wafer and redo fusion. Conclusions Expandable cages are a recent innovation; as such, efficacy and complication data are limited. As with any new device, there exists potential for mechanical failure, as occurred in the case presented.