caa a22 4500 445834072 CHVBK 20180317145325.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s00586-011-1824-4 doi (NATIONALLICENCE)springer-10.1007/s00586-011-1824-4 Polymethylmethacrylate augmentation of the pedicle screw: the cement distribution in the vertebral body [Elektronische Daten] [Ming-Hsien Hu, Hung Wu, Ming-Chau Chang, Wing-Kuang Yu, Shih-Tien Wang, Chien-Lin Liu] Many studies have proven that the polymethylmethacrylate (PMMA) augmentation of the pedicle screw can significantly increase stiffness and strength of spinal fixation. Some major complications have also been reported. However, there are no reports discussing cement distribution and its morphology in the osteoporotic vertebral body, which is critical in the analysis of the biomechanical strength of the pedicle screw and the risk of cement leakage after pedicle screw augmentation. In this study, we used computed tomography (CT) to evaluate the cement distribution in the osteoporotic vertebral body after PMMA augmentation of a pedicle screw and to analyze the factors leading to cement leakage. Two groups of patients were studied. Group A consisted 25 osteoporotic patients (mean age of 73years) with spinal instrumentation who had a total of 145 pedicle screws and cement augmentation with biopsy needles. Group B consisted of 23 osteoporotic patients (mean age of 74.6years) with spinal instrumentation who had a total of 125 cannulated pedicle screws with cement augmentation. All patients had CT evaluation of the cement distribution in the vertebral body after the surgery. The cement distribution in the vertebrae was divided into four zones in the axial CT view: anterior one-third, middle third, and posterior third of vertebral body, and the pedicle. The morphology of the cement distribution around the pedicle screw was defined as scattered type or concentrate type. The leakage pattern was divided to anterior-lateral, posterior-lateral, and canal leakage. The correlations among bone mineral density (BMD), the cement leakage rate, and cement distribution morphology were also analyzed. The results showed that most augmented pedicle screws had cement extension into three of the four zones of the vertebral body (66.3%), followed by two zones (20%), all four zones (11.5%), and only one zone (2.2%). Overall, 123 screws (84.8%) in Group A and 108 screws (86.4%) in Group B had cement concentrate type distribution. The cement leakage rate in Group A is 18.3% and 13.6% in Group B. Patients with a BMD <0.6g/cm2 had significantly higher rates of cement leakage and tended toward a scattered cement distribution. There was only one patient who had a symptomatic leakage (sciatica) in Group B. We concluded that the cement distribution after pedicle screw augmentation with biopsy needle or cannulated screw technique was mostly localized in three zones of the vertebral body, and patients with lower BMD had a higher risk of cement leakage and scattered cement distribution. Springer-Verlag, 2011 Cannulated pedicle screw nationallicence Cement augmentation nationallicence Osteoporosis nationallicence Polymethylmethacrylate nationallicence Hu Ming-Hsien Orthopedic Department, Show Chwan Memorial Hospital, Changhua, Taiwan, ROC aut Wu Hung Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC aut Chang Ming-Chau Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, 201, sec.2, Shih-Pai Road, Taipei, Taiwan, ROC aut Yu Wing-Kuang Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, 201, sec.2, Shih-Pai Road, Taipei, Taiwan, ROC aut Wang Shih-Tien Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, 201, sec.2, Shih-Pai Road, Taipei, Taiwan, ROC aut Liu Chien-Lin Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, 201, sec.2, Shih-Pai Road, Taipei, Taiwan, ROC aut European Spine Journal Springer-Verlag 20/8(2011-08-01), 1281-1288 0940-6719 20:8<1281 2011 20 586 https://doi.org/10.1007/s00586-011-1824-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00586-011-1824-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hu Ming-Hsien Orthopedic Department, Show Chwan Memorial Hospital, Changhua, Taiwan, ROC aut NATIONALLICENCE 700 1- Wu Hung Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC aut NATIONALLICENCE 700 1- Chang Ming-Chau Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, 201, sec.2, Shih-Pai Road, Taipei, Taiwan, ROC aut NATIONALLICENCE 700 1- Yu Wing-Kuang Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, 201, sec.2, Shih-Pai Road, Taipei, Taiwan, ROC aut NATIONALLICENCE 700 1- Wang Shih-Tien Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, 201, sec.2, Shih-Pai Road, Taipei, Taiwan, ROC aut NATIONALLICENCE 700 1- Liu Chien-Lin Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, 201, sec.2, Shih-Pai Road, Taipei, Taiwan, ROC aut NATIONALLICENCE 773 0- European Spine Journal Springer-Verlag 20/8(2011-08-01), 1281-1288 0940-6719 20:8<1281 2011 20 586 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer