title: Agreement on the Level Selection in Laminoplasty among Experienced Surgeons: A Survey-Based Study.
abstract: METHODS
  Survey based study.
  
  
  OBJECTIVE
  To assess the degree of agreement in level selection of laminoplasty (LP) for the selected cervical myeloradiculopathy cases between experienced spine surgeons.
  
  
  BACKGROUND
  Although, cervical LP is a widely used surgical technique for multi-level spinal cord compression, until now there is no consensus about how many segments or which segments should be opened to achieve a satisfactory decompression.
  
  
  METHODS
  Thorough clinical and radiographic data (plain X-ray, computed tomography, and magnetic resonance imaging) of 30 patients who had cervical myelopathy were prepared. The data were provided to three independent spine surgeons with over 10 years experience in operation of their own practices. They were questioned about the most preferable surgical method and suitable decompression levels. The second survey was carried out after 6 months with the same cases. If the level difference between respondents was a half level or below, agreement was considered acceptable. The intraobserver and interobserver agreements in level selection were assessed by kappa statistics.
  
  
  RESULTS
  Three respondents selected LP as an option for 6, 8, and 22 cases in the first survey and 10, 21, and 24 cases in the second survey. The reasons for selection of LP were levels of ossification of the posterior longitudinal ligament (p=0.004), segmental kyphotic deformity (p=0.036) and mean compression score (p=0.041). Intraobserver agreement showed variable results. Interobserver agreement was poor to fair by perfect matching (kappa=0.111-0.304) and fair to moderate by acceptable matching (kappa=0.308-0.625).
  
  
  CONCLUSIONS
  The degree of agreement for level selection of LP was not high even though experienced surgeons would choose the opening segments on the basis of same criteria. These results suggest that more specific guidelines in determination of levels for LP should be required to decrease unnecessary wide decompression according to individual variance.
authors: Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Jae Hwan
authors: JH
authors: Cho
authors: Department of Orthopaedic Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors: Kyung-Soo
authors: KS
authors: Suk
authors: Department of Orthopedic Surgery, Uijeongbu St. Mary's Hospital, Uijeongbu, Korea.
authors: Jong-Beom
authors: JB
authors: Park
authors: Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Jung-Ki
authors: JK
authors: Ha
authors: Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Chang Ju
authors: CJ
authors: Hwang
authors: Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Choon Sung
authors: CS
authors: Lee
authors: Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors: Dong-Ho
authors: DH
authors: Lee
keywords: Cervical vertebrae; Laminoplasty; Spinal cord comression; Surveys and questionnaires