title: Biomechanical effects of cement distribution in the fractured area on osteoporotic vertebral compression fractures: a three-dimensional finite element analysis.
abstract: BACKGROUND
  According to some clinical studies, insufficient cement distribution (ID) in the fractured area and asymmetrical cement distribution around the fractured area were thought to be the reasons for unrelieved pain and recollapse after percutaneous vertebral augmentation (PVA) in the treatment of symptomatic osteoporotic vertebral compression fractures.
  
  
  METHODS
  Finite element methods were used to investigate the biomechanical variance among three patterns of cement distribution (ID and sufficient cement distribution in the fractured area and asymmetrical cement distribution around the fractured area including upward [BU] and downward [BD] cement distribution).
  
  
  RESULTS
  Compared with fractured vertebra before PVA, distribution of von Mises stress in the cancellous bone was transferred to be concentrated at the cancellous bone surrounding cement after PVA, whereas it was not changed in the cortical bone. Compared with sufficient cement distribution group, maximum von Mises stress in the cancellous bone and cortical bone and maximum displacement of augmented vertebra increased significantly in the ID group, whereas asymmetrical cement distribution around the fractured area in BU and BD groups mainly increased maximum von Mises stress in the cancellous bone significantly. Similar results could be seen in all loading conditions.
  
  
  CONCLUSIONS
  ID in the fractured area may lead to unrelieved pain after PVA in the treatment of symptomatic osteoporotic vertebral compression fractures as maximum displacement of augmented vertebral body increased significantly. Both ID in the fractured area and asymmetrical cement distribution around the fractured area are more likely to induce recollapse of augmented vertebra because they increased maximum von Mises stress in the cancellous bone and cortical bone of augmented vertebra significantly.
authors: Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China.
authors: De
authors: D
authors: Liang
authors: Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China; Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China.
authors: Lin-Qiang
authors: LQ
authors: Ye
authors: Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China; Department of Digital Orthopaedics and Biomechanics, Laboratory Affiliated to National Key Discipline of Orthopaedics and Traumatology of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China. Electronic address: spinedrjxb@sina.com.
authors: Xiao-Bing
authors: XB
authors: Jiang
authors: Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China; Orthopaedics Hospital, Guangzhou General Hospital of Guangzhou Military Command of PLA, Guangzhou, Guangdong, People's Republic of China.
authors: Pan
authors: P
authors: Yang
authors: Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China; Department of Digital Orthopaedics and Biomechanics, Laboratory Affiliated to National Key Discipline of Orthopaedics and Traumatology of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China.
authors: Guang-Quan
authors: GQ
authors: Zhou
authors: Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China.
authors: Zhen-Song
authors: ZS
authors: Yao
authors: Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China.
authors: Shun-Cong
authors: SC
authors: Zhang
authors: Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China.
authors: Zhi-Dong
authors: ZD
authors: Yang
mesh_terms: D001696:Biomechanical Phenomena; D001843:Bone Cements; D020342:Finite Element Analysis; D050815:Fractures, Compression / Q000628:therapy*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008954:Models, Biological; D058866:Osteoporotic Fractures / Q000628:therapy*; D016103:Spinal Fractures / Q000628:therapy*
chemical_list: D001843:Bone Cements
keywords: Cement distribution; Finite element analysis; Fractured area; Osteoporotic vertebral compression fracture; Percutaneous vertebral augmentation