Comparison of titanium and polyetheretherketone (PEEK) cages in the surgical treatment of single level lumbar spondylolisthesis
Background: Pseudarthrosis is one of the complications after posterior lumbar intervertebral body fusion (PLIF). We reviewed our initial experience with PLIF using a 3D-printed porous titanium cage and examined the pertinent literature for this report. Patients and methods: This study included 20 patients who underwent one level PLIF for lumbar spondylolisthesis. All patients were followed for at least 1 year. The median follow-up duration was 23 months (range, 12 to 96). Between July 2012 and January 2014, 10 patients underwent PLIF using a PEEK carbon cage (PK group). Between November 2017 and June 2019, 10 patients underwent PLIF using a 3D porous titanium alloy cage (3DTA group). We evaluated bone fusion by CT multi-planar reconstruction at 3 days, 3 months, 6 months, and 12 months postoperatively. Results: Bony union was achieved in 8 of 10 cases in the PK group and in all cases in the 3DTA group. In the 3DTA group, all patients had bony fusion within one year. Median bone fusion periods were 6.0 months in the PK group and 6.0 months in the 3DTA group. There was no screw loosening or correction loss in either group. Cage subsidence occurred in 5 cases in the PK group and 3 cases in the 3DTA group. Conclusions: all patients in the 3DTA group achieved bone fusion within one year. The 3D porous titanium alloy cage can be expected to achieve bone fusion as good as the PEEK cage in single level PLIF surgery.