Man-Kyu Park1, Kyoung-Tae Kim2, Woo-Seok Bang3, Dae-Chul Cho4, Joo-Kyung Sung4, Young-Seok Lee5, Chang Kyu Lee6, Chi Heon Kim7, Brian K Kwon8, Won-Kee Lee9, Inbo Han10. 1. Department of Neurosurgery, Parkweonwook Hospital, 130, 4, Gwangan-ro, Suyeong-gu, Busan 48298, Republic of Korea. 2. Department of Neurosurgery, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, 130, Dongdeok-ro, Jung-gu, Daegu 41944, Republic of Korea. Electronic address: nskimkt7@gmail.com. 3. Department of Neurosurgery, Daegu Chamtntn hospital, 1807, Dalgubeol-daero, Seo-gu, Daegu, Republic of Korea. 4. Department of Neurosurgery, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, 130, Dongdeok-ro, Jung-gu, Daegu 41944, Republic of Korea. 5. Department of Neurosurgery, Gyeongsang National University School of Medicine, Jinju, Republic of Korea. 6. Department of Neurosurgery, Keimyung University Dongsan Medical Center, Jung-gu, Daegu, Republic of Korea. 7. Department of Neurosurgery, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Republic of Korea. 8. International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Blusson Spinal Cord Centre, 818 West 10th Avenue, Vancouver, British Columbia V5Z 1M9, Canada; Vancouver Spine Surgery Institute, Department of Orthopaedics, University of British Columbia, Blusson Spinal Cord Centre, 818 West 10th Avenue, Vancouver, British Columbia V5Z 1M9, Canada. 9. Medical Research Collaborating Center in Kyungpook National University Hospital, School of Medicine, Kyungpook National University, Daegu, Republic of Korea. 10. Department of Neurosurgery, CHA University, School of Medicine, CHA Bundang Medical Center, Seongnam-si, Gyeonggido, Republic of Korea.
Abstract
BACKGROUND CONTEXT: Transforaminal lumbar interbody fusion (TLIF) is a widely accepted surgical procedure, but cage migration (CM) and cage retropulsion (CR) are associated with poor outcomes. PURPOSE: This study seeks to identify risk factors associated with these serious events. STUDY DESIGN: A prospective observational longitudinal study. PATIENT SAMPLE: Over a 5-year period, 881 lumbar levels in 784 patients were treated using TLIF at three spinal surgery centers. OUTCOME MEASURES: We evaluated the odds ratio of the risk factors for CM with and without subsidence and CR in multivariate analysis. METHODS: Our study classified CM into two subgroups: CM without subsidence and CM with subsidence. Cases of spinal canal and/or foramen intrusion of the cage was defined separately as CR. Patient records, operative notes, and radiographs were analyzed for factors potentially related to CM with subsidence, CM without subsidence, and CR. RESULTS: Of 881 lumbar levels treated with TLIFs, CM without subsidence was observed in 20 (2.3%) and CM with subsidence was observed in 36 (4.1%) patients. Among the CM cases, CR was observed in 17 (17/56, 30.4%). The risk factors of CM without subsidence were osteoporosis (OR 8.73, p < .001) and use of a unilateral single cage (OR 3.57, p < .001). Osteoporosis (OR 5.77, p < .001) and endplate injury (OR 26.87, p < .001) were found to be significant risk factors for CM with subsidence. Risk factors of CR were osteoporosis (OR 7.86, p < .001), pear-shaped disc (OR 8.28, p = .001), endplate injury (OR 18.70, p < .001), unilateral single cage use (OR 4.40, p = .03), and posterior cage position (OR 6.45, p = .04). A difference in overall fusion rates was identified, with a rate of 97.1% (801 of 825) for no CM, 55.0% (11 of 20) for CM without subsidence, 41.7% (15 of 36) for CM with subsidence, and 17.6% (3 of 17) for CR at 1.5 years postoperatively. CONCLUSIONS: Our results suggest that osteoporosis is a significant risk factor for both CM and CR. In addition, a pear-shaped disc, posterior positioning of the cage, the presence of endplate injury and the use of a single cage were correlated with the CM with and without subsidence and CR.
BACKGROUND CONTEXT: Transforaminal lumbar interbody fusion (TLIF) is a widely accepted surgical procedure, but cage migration (CM) and cage retropulsion (CR) are associated with poor outcomes. PURPOSE: This study seeks to identify risk factors associated with these serious events. STUDY DESIGN: A prospective observational longitudinal study. PATIENT SAMPLE: Over a 5-year period, 881 lumbar levels in 784 patients were treated using TLIF at three spinal surgery centers. OUTCOME MEASURES: We evaluated the odds ratio of the risk factors for CM with and without subsidence and CR in multivariate analysis. METHODS: Our study classified CM into two subgroups: CM without subsidence and CM with subsidence. Cases of spinal canal and/or foramen intrusion of the cage was defined separately as CR. Patient records, operative notes, and radiographs were analyzed for factors potentially related to CM with subsidence, CM without subsidence, and CR. RESULTS: Of 881 lumbar levels treated with TLIFs, CM without subsidence was observed in 20 (2.3%) and CM with subsidence was observed in 36 (4.1%) patients. Among the CM cases, CR was observed in 17 (17/56, 30.4%). The risk factors of CM without subsidence were osteoporosis (OR 8.73, p < .001) and use of a unilateral single cage (OR 3.57, p < .001). Osteoporosis (OR 5.77, p < .001) and endplate injury (OR 26.87, p < .001) were found to be significant risk factors for CM with subsidence. Risk factors of CR were osteoporosis (OR 7.86, p < .001), pear-shaped disc (OR 8.28, p = .001), endplate injury (OR 18.70, p < .001), unilateral single cage use (OR 4.40, p = .03), and posterior cage position (OR 6.45, p = .04). A difference in overall fusion rates was identified, with a rate of 97.1% (801 of 825) for no CM, 55.0% (11 of 20) for CM without subsidence, 41.7% (15 of 36) for CM with subsidence, and 17.6% (3 of 17) for CR at 1.5 years postoperatively. CONCLUSIONS: Our results suggest that osteoporosis is a significant risk factor for both CM and CR. In addition, a pear-shaped disc, posterior positioning of the cage, the presence of endplate injury and the use of a single cage were correlated with the CM with and without subsidence and CR.