Modic Changes

Type I

Decreased signal on T1, and increased signal on T2.

Represents marrow edema.

Associated with an acute process.

Histological examination shows disruption and fissuring of the endplate and vascularized fibrous tissues within the adjacent marrow

Type II – the most common type

Increased signal on T1, and isointense or slightly hyperintense signal on T2.

Represents fatty degeneration of subchondral marrow.

Associated with a chronic process.

Histological examination shows endplate disruption with yellow marrow replacement in the adjacent vertebral body.

Type I changes convert to Type II changes with time, while Type II changes seem to remain stable.

Type III

Decreased signal on both T1 and T2.

Correlate with extensive bony sclerosis on plain radiographs.

Histological examination shows dense woven bone; hence, no marrow to produce MRI signal.