NEUROSURGERY VOLUME 64 | NUMBER 5 | MAY 2009 | 955 CLINICAL STUDIES Jay Jagannathan, M.D. Department of Neurological Surgery, University of Virginia Health Sciences Center, University of Virginia, Charlottesville, Virginia Charles A. Sansur, M.D., M.H.Sc. Department of Neurological Surgery, University of Virginia Health Sciences Center, University of Virginia, Charlottesville, Virginia Rod J. Oskouian, Jr., M.D. Department of Neurological Surgery, University of Virginia Health Sciences Center, University of Virginia, Charlottesville, Virginia Kai-Ming Fu, M.D., Ph.D. Department of Neurological Surgery, University of Virginia Health Sciences Center, University of Virginia, Charlottesville, Virginia Christopher I. Shaffrey, M.D. Department of Neurological Surgery, University of Virginia Health Sciences Center, University of Virginia, Charlottesville, Virginia Reprint requests: Christopher I. Shaffrey, M.D., Department of Neurological Surgery, University of Virginia Health Sciences Center, Box 800212, Charlottesville, VA 22902. Email: cis8z@hscmail.mcc.virginia.edu Received, May 21, 2008. Accepted, December 8, 2008. Copyright © 2009 by the Congress of Neurological Surgeons L oss of lordosis can result from degenera- tive changes of the lumbar spine. Surgical techniques for instrumented lumbar fusion have historically resulted in further loss of lordosis with the development of focal kyphosis and/or sagittal imbalance (3, 4, 12, 13). Clinical characteristics associated with de- creased lumbar lordosis and sagittal imbalance include back pain, lower extremity pain, and weakness (20). These symptoms, along with radiographic findings, generally worsen with time, as adjacent kyphotic motion segments receive eccentric loading, progressively wors- ening the deformity. Because of the complexity of surgical recon- structive procedures to correct sagittal imbal- ance, a variety of techniques have been used to enhance restoration of lumbar lordosis during the initial surgical procedure. Several reports ABBREVIATIONS: CT, computed tomographic; PLIF, posterior lumbar interbody fusion; rhBMP-2, recombinant human bone morphogenetic protein 2; TLIF, transforaminal lumbar interbody fusion RADIOGRAPHIC RESTORATION OF LUMBAR ALIGNMENT AFTER TRANSFORAMINAL LUMBAR INTERBODY FUSION OBJECTIVE: Restoration of lumbar lordosis is a critical factor in long-term success after lumbar fusions. Transforaminal lumbar interbody fusion (TLIF) is a popular surgical technique in the lumbar spine, but few data exist on change in spinal alignment after the procedure. METHODS: Eighty patients who underwent TLIF surgery were retrospectively reviewed (minimum follow-up period, 2 years). Standing x-rays were assessed for changes in focal and segmental kyphosis, and restoration of lumbar lordosis. Improvement in spondylolis- thesis, sagittal balance, and scoliosis were also assessed. Fusion was assessed as well. RESULTS: Eighty operations were performed at 107 levels. Mean presenting lumbar Cobb angle measurement (L1–S1) was 36.3  4.5 degrees (range, 12–77 degrees). Forty patients (50%) had sagittal imbalance. Mean postoperative Cobb angle (L1–S1) was 55.1  6.6. Thirty-three of 36 patients with segmental kyphosis (92%) had restoration of lordosis. Improvement in alignment was most prominent at the surgical level (mean increase in lordosis, 20.2  4.2 degrees). The improvement in lumbar lordosis among patients undergoing multilevel TLIFs (27.3  3.4 degrees) was significantly higher com- pared with patients undergoing single-level operations (17.4  4.4) (Student’s t test, P = 0.0004). Thirty of the 40 patients with sagittal imbalance (75%) achieved immedi- ate restoration of normal sagittal balance. The ability to restore normal sagittal balance was correlated with a sagittal imbalance of less than 10 cm (P = 0.0001). Spondylolisthesis was completely corrected at the TLIF site in 90 of 99 levels (91%). Three patients (4%) required reoperation, 2 for implant disengagement and 1 for worsening kyphoscolio- sis above the original surgical levels. Two of the 80 patients had pseudoarthrosis; hence, the rate of pseudoarthrosis was 2.5%. CONCLUSION: The TLIF operation is highly effective in improving spinal alignment in patients with degenerative spinal disorders when the appropriate surgical technique is implemented. KEY WORDS: Fusion, Kyphosis, Lordosis, Outcomes, Radiographic, Transforaminal lumbar interbody fusion Neurosurgery 64:955–964, 2009 DOI: 10.1227/01.NEU.0000343544.77456.46 www.neurosurgery-online.com