Five years follow up after MIS TLIF vs MIS decompression for Grade 1 Spondylolisthesis: Is there any difference in outcomes?

Introduction: Here, we compare 5-year outcomes of MIS transforaminal lumbar interbody fusion (TLIF) versus MIS decompression alone for grade 1 spondylolisthesis.

Methods: We analyzed patients who underwent single-segment MIS TLIF or MIS tubular decompression for grade 1 degenerative lumbar spondylolisthesis from the prospective QOD spondylolisthesis cohort. Univariate and multivariable analyses compared outcomes including Oswestry Disability Index (ODI), numeric rating scale (NRS) back pain (NRS-BP), NRS leg pain (NRS-LP), EuroQol-5D (EQ-5D), North American Spine Society (NASS) satisfaction score, and cumulative related reoperation rate.

Results: Overall, 143 underwent MIS surgery: 72 (50.3%) TLIF and 71 (49.7%) decompression. The MIS TLIF cohort was younger (62.1±10.5 vs 72.3±9.6 years), had lower rates of diabetes (9.7% vs 22.5%), was more likely to ambulate independently (88.9% vs 85.9%), use private insurance (65.3% vs 26.8%), be employed preoperatively (54.2% vs 23.9%), and had higher baseline NRS-BP (6.9±2.6 vs 5.6±3.2) (p < 0.05). Otherwise, the cohorts were similar for baseline characteristics. MIS TLIF had more blood loss (108.8±85.0 vs 33.0±63.2 mls), longer operative times (228.2±110.7 vs 101.8±48.0 mins), and longer hospitalization lengths (2.9±1.8 vs 0.7±1.2 days) (p < 0.001).
Five years postoperatively, both cohorts had significant mean improvements in ODI, NRS-LP, NRS-BP, and EQ-5D (p < 0.05). MIS TLIF demonstrated significantly larger reductions in NRS-BP (-4.0±3.5 vs -2.2±3.4) and higher rates of satisfaction (NASS 1 or 2: 81.4% vs 57.6%) (p < 0.05), but similar ODI, NRS-LP, NRS-BP, and EQ-5D (p>0.05). MCID rates for ODI, NRS-LP, NRS-BP, and EQ-5D were equivalent between the cohorts (p>0.05). MIS TLIF had a significantly lower reoperation rate (5.6% vs 15.5%, p=0.001). Multivariate analyses did not identify fusion as a significant predictor of ODI, NRS-LP, NRS-BP, and EQ-5D.

Conclusion : While both MIS TLIF and MIS decompression are associated with clinical benefits in well-selected patients, our 5-year results demonstrate that MIS TLIF is associated with fewer reoperations and higher patient satisfaction.