Continuous distraction-induced delayed spinal cord injury on motor-evoked potentials and histological changes of spinal cord in a porcine model

J. Y. Hong, S. W. Suh, S. H. Lee, J. H. Park, S. Y. Park, I. J. Rhyu, J. H. Yang

Research output: Contribution to journalArticle


Study design: Experimental study. Objectives: This study evaluated distraction-induced delayed spinal cord injury in a porcine model. Setting: Department of Orthopedics, Korea University Guro Hospital, Seoul, Korea. Methods: Global osteotomy of three columns was performed on the thirteenth thoracic vertebrae with 13 pigs. The osteotomized vertebrae were distracted to 57-103% of segmental vertebral height (SVH) length, which was less than the distraction length that induces prompt SCI. The vertebral height was maintained until the loss of motor-evoked potential (MEP) signals with continuous distraction. The distraction distance and the time at which SCI occurred were measured, and distraction was then released to observe MEP recovery patterns. Results: We found delayed SCI in 8 of the 12 pigs, with a mean 20.9 mm (range 19-25 mm) and 10.7 min (range 8-12 min) of continuous spinal distraction, which was equivalent to 74.3% (68-84%) of SVH and 3.63% (3.42-4.31%) of thoracolumbar spinal length. A continuous 74.3% SVH distraction over an average of 10.7 min caused a delayed SCI, which was indicated by mild histologic changes in the spinal cord. Recovery patterns from SCI after distraction release were compatible with the degree of histological change; however, these patterns differed from the previously investigated prompt type of SCI. Conclusion: Late onset injury due to continuous spinal distraction, which is comparable to iatrogenic SCI in spinal correction surgery, is important for understanding the impact of corrective surgery.

Original languageEnglish (US)
Pages (from-to)649-655
Number of pages7
JournalSpinal Cord
Issue number9
StatePublished - Sep 1 2016
Externally publishedYes


ASJC Scopus subject areas

  • Neurology
  • Clinical Neurology

Cite this