Reliability and reproducibility of morphologic classification for thoracic pedicles in scoliosis

English Keywords:Scoliosis  Pedicle  Morphologic classification  Reliability  Reproducibility

English Abstract:

  【Abstract】 Objectives: To investigate the reliability and inter-observer reproducibility of scoliosis thoracic pedicle classification system and its clinical applications. Methods: From January 1998 to January 2009, 60 patients with scoliosis underwent surgical treatment, preoperative CT scan was performed in all patients, and the pedicle of vertebral arch axis thin layer reconstruction was performed. According to the morphological characteristics of cancellous bone, the thoracic pedicles were divided into normal type, narrow type, isthmic sclerosis, complete sclerosis(including two subtypes of concave sclerosis and straight sclerosis) and the pedicle absence. Bsaed on the 64-slice CT technology, multi-layer reconstruction, the 1440 thoracic pedicle axial CT scan results from the 60 cases were classified by three senior spine surgeons who knew nothing about the research at the same time. A month later, the procedure repeated. Statistical analysis on multiple categories and multiple observers was performed by Stata 10.0 software and the Kappa statistics to evaluate the credibility of inter-observer and the repeatability of intra-observer. Results: For the first results of classification among the three senior spine surgeons: the percentage of result for three spine surgeons was 88%, 84% and 92% respectively, and the Kappa coefficients was 0.7647, 0.6590 and 0.8292 respectively; while for the second results from the same spine surgeon: the percentage of result was 95%, 97% and 96% respectively, and the Kappa coefficient was 0.9227, 0.9513 and 0.9117 respectively. Conclusions: The morphologic classification of thoracic pedicles in scoliosis has moderate reliability and excellent reproducibility.