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A distinction should be made between 107669003 |Degenerative abnormality (morphologic abnormality)| and 33359002 |Degeneration (morphologic abnormality)|.

33359002 |Degeneration (morphologic abnormality)| is a child of 107669003 |Degenerative abnormality (morphologic abnormality)|.
107669003 |Degenerative abnormality (morphologic abnormality)| is a grouper concept with members usually characterized by retrogressive pathologic structural changes. Diseases that are degenerative do not necessarily have 116676008 |Associated morphology (attribute)| of 33359002 |Degeneration (morphologic abnormality)|, since the word degenerative sometimes refers to loss of function rather than structural degeneration.

Examples include degeneration proper, as well as lysis, vascular sclerosis, necrosis, infarct, deposition, dystrophy, pigmentation, atrophy, and depletion.

Morphologies under degeneration also have retrogressive structural changes, but they are not necessarily any of the above, nor are they necessarily resorption, malacia, obliteration, opacity, plaque, or postmortem change (this seems to be definition by exclusion).
Necrosis is a degenerative abnormality, but not a degeneration. Necrosis can follow degeneration.
Atrophy is a degenerative abnormality, but only atrophic degeneration is also a degeneration.

33359002 |Degeneration (morphologic abnormality)| and 107669003 |Degenerative abnormality (morphologic abnormality)| should rarely, if ever, be used as the value of Associated morphology of a particular disorder; rather, a more specific subtype should be used.

Exception

It might be used as the value of Associated morphology for a broad category of degenerative disorders when the degeneration is always and necessarily structural. It is then inherited by all the subtypes, unless specialized by assigning a subtype of degeneration as the value for Associated morphology.