Study design:

A retrospective observational study.

Objective:

This study investigated the clinical and radiological results of using cortical bone trajectory (CBT) screws versus traditional pedicle (TP) screws in transforaminal lumbar interbody fusion(TLIF) during a 5-year follow-up of patients with single-level lumbar degenerative spondylolisthesis.

Summary of background data:

Few studies have compared 5-year follow-up outcomes between CBT screws and TP screws in TLIF.

Methods:

We reviewed outcome data of patients with single-level lumbar degenerative spondylolisthesis who underwent TLIF procedures with CBT screws (131 patients) or TP screws (80 patients) between 2011 and 2015. Patient-reported clinical outcome data included Oswestry Disability Index (ODI) scores and visual analog scale (VAS) scores for back and leg pain at baseline, 6 months, and 1 year, 2 years, and 5 years postoperatively. The radiographic fusion rate and prevalence of secondary surgery for adjacent segment disease were also measured.

Results:

During the follow-up over 5 years, the CBT group had significantly lower VAS scores for back pain (P<0.0001, respectively). At 2 years after surgery, the CBT group had significantly higher VAS scores for leg pain (P=.007). At 5 years postoperatively, no significant differences existed in the VAS score for leg pain or in the ODI score between the two groups. Radiographic fusion rates (CBT vs. TP: 95.5% vs. 95.9%; P=0.881) and adverse events during the 5 years after surgery were not significantly different. At 2 years postoperatively, the prevalence of secondary surgery to treat adjacent segment disease was significantly different between the two groups (CBT vs. TP: 13.7% vs. 5.0%; P=0.044).

Conclusions:

Our results suggest that, during a 5-year follow-up, CBT screws for TLIF were an effective treatment, compared to TP screws, for patients with single-level lumbar degenerative spondylolisthesis. However, when performing CBT screws for TLIF, surgeons should consider a symptomatic adjacent segment disease requiring surgery.