Medical & Biological Engineering & Computing

, Volume 48, Issue 2, pp 185–195 | Cite as

Computer-aided assessment of scoliosis on posteroanterior radiographs

  • Junhua Zhang
  • Edmond Lou
  • Douglas L. Hill
  • James V. Raso
  • Yuanyuan Wang
  • Lawrence H. Le
  • Xinling Shi
Original Article


In order to reduce the observer variability in radiographic scoliosis assessment, a computer-aided system was developed. The system semi-automatically measured the Cobb angle and vertebral rotation on posteroanterior radiographs based on Hough transform and snake model, respectively. Both algorithms were integrated with the shape priors to improve the performance. The system was tested twice by each of three observers. The intraobserver and interobserver reliability analyses resulted in the intraclass correlation coefficients higher than 0.9 and 0.8 for Cobb measurement on 70 radiographs and rotation measurement on 156 vertebrae, respectively. Both the Cobb and rotation measurements resulted in the average intraobserver and interobserver errors less than 2° and 3°, respectively. There were no significant differences in the measurement variability between groups of curve location, curve magnitude, observer experience, and vertebra location. Compared with the documented results, measurement variability is reduced by using the developed system. This system can help orthopedic surgeons assess scoliosis more reliably.


Scoliosis Cobb angle Vertebral rotation Computer-aided measurement Radiograph 



This work was supported by General Program for Applied Basic Research of Yunnan Province (2008CD079), and Science and Technology Research Project of Yunnan University (2009F33Q).


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Copyright information

© International Federation for Medical and Biological Engineering 2009

Authors and Affiliations

  • Junhua Zhang
    • 1
  • Edmond Lou
    • 2
  • Douglas L. Hill
    • 2
  • James V. Raso
    • 2
  • Yuanyuan Wang
    • 3
  • Lawrence H. Le
    • 4
  • Xinling Shi
    • 1
  1. 1.Department of Electronic EngineeringYunnan UniversityKunmingChina
  2. 2.Department of Rehabilitation TechnologyGlenrose Rehabilitation HospitalEdmontonCanada
  3. 3.Department of Electronic EngineeringFudan UniversityShanghaiChina
  4. 4.Department of Radiology and Diagnostic ImagingUniversity of AlbertaEdmontonCanada

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