RT Journal Article SR Electronic T1 Radiographic Factors Affecting Lordosis Correction After Transforaminal Lumbar Interbody Fusion With Unilateral Facetectomy JF International Journal of Spine Surgery JO Int J Spine Surg FD International Society for the Advancement of Spine Surgery SP 681 OP 686 DO 10.14444/7099 VO 14 IS 5 A1 MARTIN, CHRISTOPHER T. A1 NIU, SHUO A1 WHICKER, EMILY A1 WARD, LAURA A1 YOON, S. TIM YR 2020 UL https://www.ijssurgery.com/content/14/5/681.abstract AB Background: The study design was a retrospective cohort study. The objective was to identify preoperative (preop) radiographic features that are associated with increased lordosis correction after transforaminal lumbar interbody fusion (TLIF).Methods: We retrospectively reviewed a single surgeon series of TLIF performed at L4–5 since 2010. The surgical technique involved unilateral facetectomy and insertion of a banana-type cage. A total of 107 cases were available with plain radiographs, and 62 with a preop computed tomography (CT) scan. We compared segmental lordosis correction between the preop and 6-week postoperative radiographs. Patients were divided into groups of those with or without more than 5° lordosis correction. Radiographic features were then compared, and a multivariate analysis was performed.Results: The mean lordosis correction of the entire cohort was 2.5° (range = −9° to 16°). The percentage of patients with a vacuum disc on the preop CT (40% vs 10%, P = 0.01) was higher in the group with greater than 5° lordosis correction, whereas the mean preop segmental lordosis (14.3° vs 18.6°) and the preop segmental disc angle (6.4° vs 8.4°) were both lower (P < 0.05 for each). The percentage of patients with a Meyerding grade of 2 or higher (28% vs 16%) trended higher but was not significant (P = 0.1). There was no significant difference in the mean body mass index, patient age, preop lumbar lordosis, or disc space height.Conclusions: Patients with a preop vacuum disc sign on CT scan or those with a more kyphotic disc space on preop radiographs were more likely to achieve lordosis correction. This information may be useful in preop planning.Level of Evidence: 4.Clinical Relevance: Unilateral TLIF is likely to be neutral or kyphogenic in patients with a segmental disc angle that is neutral or lordotic pre-operatively, but is likely to increase segmental lordosis in patients with a disc angle that is kyphotic pre-oepratively.