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What is Denis gave how many columns theory to define stability of spine: and explain in detail?
(c) 3ExplanationDenis' Three-Column Theory- Proposed by Francis Denis, three-column concept divides a spinal segment into three parts: Anterior, middle, and posterior colums.- The anterior column comprises the anterior longitudinal ligament and the anterior half of the vertebral body; the middle column comprises the posterior half of the vertebral body and the posterior longitudinal ligament; the posterior column comprises the pedicles, the facet joints and the supraspinous ligaments.- Significance: If 2 out of 3 columns are involved it is labelled as unstable spinal injury.Denis 3 columns