Musculoskeletal Imaging

Sequestration

the formation of a sequestrum, such as occurs in haematogenous osteomyelitis or discal herniation.

In osteomyelitis, sequestration results from deprivation of blood supply to the bone cortex as a consequence of thrombosis of metaphyseal vessels and interruption of periosteal vessels; cortical necrosis may also be present.

Discal sequestration involves displacement of the nucleus pulposus, which may penetrate the posterior longitudinal ligament and come to lie within the epidural space.

DR