A sequestered disc is a herniated disc where the displaced disc material is completely unattached to the disc itself. There is no continuity between the primary disc itself and the herniated part of the disc. A sequestered disc is a sub-classification of the disc extrusion.
A representation of a sequestered disc is shown below.
References
Fardon DF, Williams AL, Dohring EJ, Murtagh FR, Gabriel Rothman SL, Sze GK. Lumbar disc nomenclature: version 2.0: Recommendations of the combined task forces of the North American Spine Society, the American Society of Spine Radiology and the American Society of Neuroradiology. Spine J. 2014 Nov 1;14(11):2525-45. doi: 10.1016/j.spinee.2014.04.022. Epub 2014 Apr 24. Review. PubMed PMID: 24768732.
