Influence of Preoperative Difference in Lumbar Lordosis Between the Standing and Supine Positions on Clinical Outcomes After Single-Level Transforaminal Lumbar Interbody Fusion: Minimum 2-Year Follow-Up.

Abstract

STUDY DESIGN\nRetrospective cohort study.\n\n\nOBJECTIVE\nTo investigate whether a preoperative difference in lumbar lordosis (D-LL) between the standing and supine positions is associated with clinical outcomes after transforaminal lumbar interbody fusion (TLIF).\n\n\nSUMMARY OF BACKGROUND DATA\nSeveral factors have been reported to be associated with surgical outcomes after TLIF. However, the association between preoperative D-LL and clinical outcomes after TLIF is unknown.\n\n\nMETHODS\nWe enrolled 45 lumbar degenerative disease patients (mean age: 65.7\u200a±\u200a11.3\u200ayears old; 24 male) treated with single-level TLIF. Surgical outcomes were assessed using Oswestry disability index, visual analog scale (VAS; low back pain (LBP), lower-extremity pain, numbness, LBP in motion, in standing, and in sitting), Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, Japanese Orthopaedic Association score for intermittent claudication (JOA score), and Nakai s scoring system. The preoperative D-LL between the standing radiograph and computed tomography (CT) in the supine position was defined as LL in supine CT-standing radiograph. Patients were divided into two groups according to D-LL value (D-LL > -4°, and D-LL ≤ -4°). Clinical outcomes were compared between the groups, and correlations between preoperative D-LL and clinical outcomes were analyzed.\n\n\nRESULTS\nThere were no significant differences in preoperative clinical parameters between the two groups. Postoperative VASs for lower extremity pain, numbness, LBP in standing, and JOA score in D-LL > -4° group were significantly worse than in the D-LL ≤ -4° group (P\u200a<\u200a0.05). Preoperative D-LL showed a weak correlation with postoperative lower extremity pain and numbness (P\u200a<\u200a0.05).\n\n\nCONCLUSIONS\nThis study revealed that lumbar degenerative disease patients, who have greater preoperative kyphotic lumbar alignment in the standing versus supine position, tend to have postoperative residual symptoms after TLIF. A preoperative comparison of lateral radiographs between the standing and supine positions is useful to predict patients postoperative residual symptoms.Level of Evidence: 3.