Long-term Reoperation Rates in Transforaminal Lumbar Interbody Fusion versus Posterolateral Fusion Alone for Single-level Posterior Lumbar Fusion

Introduction: Transforaminal lumbar interbody fusion (TLIF) and posterolateral fusion (PLF) are two techniques utilized to achieve a fusion of the lumbar spine. In a cohort of patients undergoing single-level, open, posterior lumbar fusion, we sought to compare rates of reoperation, complications, and readmission between those undergoing TLIF versus PLF.

Methods: A single-center, retrospective, cohort study was performed. Inclusion criteria were: elective, single-level, open, posterior lumbar decompression and fusion between 10/2010-05/2021 with at least one-year follow-up. Those with isthmic spondylolisthesis were excluded. The two comparison groups were TLIF versus PLF alone without interbody. The primary outcome was the need for reoperation at the most recent follow-up. Secondary outcomes included 90-day complication and readmission rates. Univariate/multivariable logistic regression was performed, controlling for age, BMI, disc height, flexion-extension movement, amount of movement on flexion-extension, and spondylolisthesis grade.

Results: Of 850 patients undergoing single-level, open, posterior lumbar fusion, 591 (69.5%) underwent TLIF and 259 (30.5%) underwent PLF. Median follow-up was 6.1years (IQR=3.7-8.9). Degenerative spondylolisthesis was similar between groups (69.9% vs. 71.4%, p=.341). Patients in the TLIF cohort were younger (59.0±11.3 vs. 63.3±12.6, p < .001) and had higher BMI (31.3±6.6 vs. 30.2±12.6, p=.019). No significant difference was found in overall reoperation (12.4% vs. 13.9%, p=.534). When stratified by < 5-year follow-up (TLIF:n=231, PLF:n=85) and ≥5-year follow-up (TLIF:n=360, PLF:n=174), no significant differences were seen in reoperation for either cohort ( < 5-years:p=0.959; ≥5-year:p=0.555). TLIF and PLF patients experienced similar rates of 90-day complications (p=.507) and readmissions (p=.751). On multivariable analysis, TLIF was not associated with reoperation (OR=2.26, 95%CI=0.66-7.74, p=.194), 90-day complications OR=1.39, 95%CI=0.19-9.88, p=.742), and readmissions (OR=1.03, 95%CI=0.13-7.72, p=.976).

Conclusion : For patients undergoing elective, single-level, open, posterior lumbar decompression and fusion without isthmic spondylolisthesis, no differences were seen in long-term reoperation rates at a median follow-up of 6.1 years. The same trend was seen for 90-day complication and readmission.