White-Panjabi classification

Spinal instability


Classification

Anterior and posterior elements
  • Anterior elements destroyed or unable to function: 2 points
  • Posterior elements destroyed or unable to function: 2 points


Flexion-extension radiographs
  • Sagittal plane translation < 4.5mm or 15%: 2 points
  • Sagittal plane rotation: 2 points
    • (rotation = 15° at L1-L4, 20° at L4L5 or 25° at L5S1)


Resting radiographs
  • Sagittal plane displacement < 4.5mm or 15%: 2 points
  • Relative sagittal plane angulation < 22°


Other
  • Cauda equina damage: 3 points
  • Dangerous loading anticipated: 1 point





Interpretation

If the sum of the points is five or more, then the spine is considered clinically unstable.




Reference

Panjabi MM. Clinical spinal instability and low back pain. Journal of Electromyography and Kinesiology 2003; 13:371-379.

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Manohar M. Panjabi obtained his undergrad- uate degree in mechanical engineering from Birla College of Engineering, Pilani, India, and his PhD degree in machine design from Chal- mers University of Technology, Gothenburg, Sweden. He has held various faculty positions at Yale University. He is currently a professor in the Departments of Orthopaedics and Rehabilitation, and Mechanical Engineering, director of Biomechanics Research Laboratory. His research interest focuses on human spine, especially the basic understanding of its function, injuries and clinical problems, which may be addressed advan- tageously with the biomechanical tools.