Objective:
This study aimed to examine whether preoperative severity and location of lumbar intervertebral disc vacuum phenomenon (VP) influence surgical outcomes after single-level transforaminal lumbar interbody fusion (TLIF).
Methods:
We included 106 patients (age: 67.4 ± 10.4 years; 51 male/55 female) with lumbar degenerative diseases, who were treated with single-level TLIF. Severity of VP (SVP) score was measured preoperatively. SVP score at fused disc was used as SVP (FS) score, and at non-fused discs was used as SVP (non-FS) score. Surgical outcomes were assessed using Oswestry disability index (ODI) and visual analogue scale (VAS; low back pain (LBP), lower-extremity pain, numbness, LBP in motion, in standing, and in sitting). The patients were divided into Severe VP (FS or non-FS) and Mild VP (FS or non-FS) groups, and surgical outcomes were compared between the two groups. Correlations between each SVP score and surgical outcomes were analyzed.
Results:
There were no differences in surgical outcomes between the Severe VP (FS) and Mild VP (FS) groups. Postoperative ODI, VAS for LBP, lower-extremity pain, numbness, and LBP in standing were significantly worse in the Severe VP (non-FS) group than in the Mild VP (non-FS) group. SVP (non-FS) scores significantly correlated with postoperative ODI, VAS for LBP, lower extremity pain, numbness, and LBP in standing; however, SVP (FS) scores did not correlate with any surgical outcomes.
Conclusion:
Preoperative severity of VP at fused disc is not associated with surgical outcomes, however, severity of VP at non-fused discs is correlated with clinical outcomes.
Keywords:
intervertebral disc degeneration; lumbar lordosis; surgical outcomes; transforaminal lumbar interbody fusion; vacuum phenomenon.