Background:

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is one of several approaches to lumbar interbody fusion that has proven to be a safe and effective treatment for symptomatic lumbar degenerative disease The clinical outcomes of TLIF are generally favorable, there is still controversy regarding its ability to restore sagittal alignment. For this reason expandable (EXP) TLIF cages have been developed and designed to be improved ability to restore disc height and segmental lordosis (SL). The use of EXP cages in TLIF has increased drastically, however, it is not entirely clear how effective the cage expansion results in disc space lordosis, distraction and long-term outcome.

Methods:

We review a cohort of patients with symptomatic lumbar degenerative disc pathology who underwent TLIF surgery at our institution. We compare clinical and radiographic outcomes of expandable versus non-expandable cage use in patients undergoing MIS-TLIF focusing on the mean changes in SL, dick height and post-operative complications. The results were compared with other studies reported in the international literature.

Results:

The results indicate that mean change in SL was not significantly different between the 2 groups. we demonstrate a significantly higher rate of post-operative subsidence in the EXP cage group CONCLUSION: This study established that EXP cage use in single level TLIFs did not reduce the rate of postoperative complications, but rather significantly increases a patient’s risk of post-operative subsidence, whereas they do not presently demonstrate improved clinical outcomes or improved sagittal alignment compared with static cages.