Related Experiment Video
Updated: Aug 19, 2026

07:25
Ovine Lumbar Intervertebral Disc Degeneration Model Utilizing a Lateral Retroperitoneal Drill Bit Injury
Published on: May 25, 2017
CT detection of retroperitoneal gas associated with gas in intervertebral disks
Journal of Computer Assisted Tomography
|April 1, 1984
Abstract:
Three cases are presented with computed tomographic evidence of gas in retroperitoneal soft tissues in association with the so-called "vacuum phenomenon" (Knutsson sign) in lumbar disks. We review the explanations of Knutsson sign and offer an explanation of how extradiscal gas can occur in association with it.
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