Transforaminal Versus Anterior Lumbar Interbody Fusion in Long Deformity Constructs A Matched Cohort Analysis

Study Design. Prospectively enrolled, retrospectively analyzed matched cohort analysis. Objective. Evaluate the relative merits of transforaminal lumbar interbody fusion (TLIF) and anterior lumbar interbody fusion (ALIF) when performed in long deformity constructs. Summary of Background Data. Interbody fusion is frequently used at the caudal levels of long-segment spinal deformity instrumentation constructs to protect the sacral implants and enhance fusion rates. However, there is a paucity of literature regarding which technique is more efficacious. Methods. Forty-two patients who underwent TLIF and 42 patients who underwent ALIF were matched with respect to age, sex, comorbidities, curve magnitude, fusion length, and ALIF/TLIF level. Radiographs and clinical outcomes were compared at minimum 2-year follow-up. Results. Age averaged 54.0 years and instrumented vertebrae averaged 13.6. TLIFs had less operative time (481 vs. 595 min, P = 0.0007), but greater blood loss (2011 vs. 1281 mL, P = 0.0002). Overall complications (TLIF, 12/42 vs. ALIF, 15/42) and neurological complications (TLIF, 4/42 vs. ALIF, 3/42) did not differ. One pseudarthrosis occurred at an ALIF level, with none at TLIF levels. Patients who underwent ALIF began with lower SRS scores but showed more improvement (44.4 to 70.7 vs. 58.6 to 70.6, P = 0.0043). ODI scores in both groups improved similarly. Regionally, ALIFs engendered more lordosis than TLIFs at L3-S1 (gain of 6.9 degrees vs. -2.6 degrees, P < 0.0001) but not T12-S1 (gain of 11.5 degrees vs. 7.9 degrees, P = 0.29). Locally, ALIFs created more lordosis at L4-L5 (gain of 5.6 degrees vs. -1.7 degrees, P < 0.0001) and L5-S1 (gain of 2.5 degrees vs. -1.4 degrees, P = 0.022), but not at L3-L4 (gain of 5.3 degrees vs. 4.0 degrees, P = 0.65). Patients who underwent TLIF obtained greater correction of anteroposterior Cobb angles in lumbar (reduction of 22.4 degrees vs. 9.9 degrees, P < 0.0001) and lumbosacral curves (reduction of 10.3 degrees vs. 3.4 degrees, P < 0.0001). Conclusion. Spinal deformity surgery used TLIFs rather than ALIFs resulted in shorter operative time with no difference in complication rates. ALIFs provided more segmental lordosis, whereas TLIFs afforded better correction of scoliotic curves.