Journal of Korean Neurosurgical Society

The Korean Neurosurgical Society (대한신경외과학회)
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Preoperative Radiological Parameters to Predict Clinical and Radiological Outcomes after Laminoplasty

  • Lee, Su Hun (Department of Neurosurgery, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital) ;
  • Son, Dong Wuk (Department of Neurosurgery, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital) ;
  • Shin, Jun Jae (Department of Neurosurgery, Yongin Severance Hospital, Yonsei University College of Medicine) ;
  • Ha, Yoon (Department of Neurosurgery, Spine and Spinal Cord Institute, Severance Hospital, Yonsei University College of Medicine) ;
  • Song, Geun Sung (Department of Neurosurgery, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital) ;
  • Lee, Jun Seok (Department of Neurosurgery, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital) ;
  • Lee, Sang Weon (Department of Neurosurgery, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital)
  • Received : 2020.10.14
  • Accepted : 2020.12.19
  • Published : 2021.09.01
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Abstract

Many studies have focused on pre-operative sagittal alignment parameters which could predict poor clinical or radiological outcomes after laminoplasty. However, the influx of too many new factors causes confusion. This study reviewed sagittal alignment parameters, predictive of clinical or radiological outcomes, in the literature. Preoperative kyphotic alignment was initially proposed as a predictor of clinical outcomes. The clinical significance of the K-line and K-line variants also has been studied. Sagittal vertical axis, T1 slope (T1s), T1s-cervical lordosis (CL), anterolisthesis, local kyphosis, the longitudinal distance index, and range of motion were proposed to have relationships with clinical outcomes. The relationship between loss of cervical lordosis (LCL) and T1s has been widely studied, but controversy remains. Extension function, the ratio of CL to T1s (CL/T1s), and Sharma classification were recently proposed as LCL predictors. In predicting postoperative kyphosis, T1s cannot predict postoperative kyphosis, but a low CL/T1s ratio was associated with postoperative kyphosis.

Keywords

Acknowledgement

This study was supported by Research institute for Convergence of biomedical science and technology (30-2018-020), Pusan National University Yangsan Hospital.

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