Preliminary Results of Expandable Transforaminal Lumbar Interbody Fusion Cages

Compared with static cages, expandable cages for Transforaminal Lumbar Interbody Fusion (TLIF), are thought to require less posterior bony removal and nerve root retraction. They may allow the creation of a greater lordotic angle and lordosis restoration.

This study investigated whether TLIF using an expandable lordotic interbody cage facilitates an improvement in both segmental lordosis and the restoration of intradiscal height.

A total of 32 patients with 40 operated segments underwent TLIF surgery for lumbar degenerative disc disease and were consecutively included in this prospective observational study. Of those patients, 25 received monosegmental treatment, six were treated bisegmentally, and one was treated trisegmentally. All patients were assessed clinically and radiographically preoperatively, as well as one week, six months, and two years postoperatively.

Two patients required revision for screw loosening and pseudarthrosis. In four patients, the endplate was violated intraoperatively due to cage placement. Postoperatively, cage subsidence was observed in four patients. Significant improvement in the mean degree of spondylolisthesis was noted at the two-year mark. Mean segmental lordosis improved postoperatively. A significant increase in mean disc height of the treated segment was also found. Overall, with the exception of pain, no significant clinical or radiographic changes were reported between the first postoperative week and the two-year year follow-up mark. The mean pain, functional, and quality of life outcomes improved significantly from the preoperative to postoperative period, with no deterioration between six months and two years.

This study demonstrates that favorable outcomes can be achieved by using an expandable titanium cage in TLIF procedures.