Lumbar alignment and patient-reported outcomes after single-level transforaminal lumbar interbody fusion for degenerative lumbar spondylolisthesis with and without local coronal imbalance.

Objective: The purpose of this study was to compare the preoperative radiographic features of degenerative lumbar spondylolisthesis (DLS) with and without local coronal imbalance (LCI) and to investigate the surgical outcomes of transforaminal lumbar interbody fusion (TLIF) in the treatment of DLS with LCI at the spondylolisthesis level. DLS with scoliotic disc wedging and/or lateral listhesis at the same involved segment, as well as LCI, constitutes a distinct subgroup. However, previous studies concerning surgical outcomes focused mainly on sagittal profiles. There is a paucity of valid data regarding lumbar coronal alignment and patient-reported outcomes (PROs) after surgery in DLS with LCI.

Methods: The authors reviewed consecutive patients who received TLIF for L4/5 DLS between 2009 and 2018. Patients were assigned to the LCI and non-LCI groups based on preoperative radiographs. Demographics, radiographic parameters related to both sagittal and coronal alignment, and PROs were compared between the 2 groups.

Results: There were 21 patients in the LCI and 80 in the non-LCI group. Compared with the non-LCI group, the LCI group was characterized by lower preoperative lumbar lordosis on sagittal alignment (38.3° vs 43.7°, p < 0.05), higher lumbar Cobb angle on coronal alignment (12.4° vs 5.1°, p < 0.05), and worse lumbar coronal balance (18.5 mm vs 6.8 mm, p < 0.05). After surgery, lumbar alignment in the sagittal and coronal planes was significantly improved in the LCI group, whereas no significant changes occurred in the non-LCI group. Scores on the preoperative Oswestry Disability Index and the visual analog scale for back pain and leg pain scores were significantly higher in the LCI group, whereas no differences were found between the 2 groups in the postoperative evaluation (p > 0.05).

Conclusions: DLS with LCI constitutes a distinct subgroup characterized by coronal malalignment and loss of whole lumbar lordosis, which may result in worse PROs. The TLIF procedure allows the reconstruction of the coronal and sagittal lumbar profile and achievement of satisfactory PROs.