arthrodesis vs arthroplasty

arthrodesis and arthroplasty both are nouns.

Word	Noun	Adjective	Verb	Adverb
arthrodesis	Yes	No	No	No
arthroplasty	Yes	No	No	No

As nouns, arthroplasty is a hypernym of arthrodesis; that is, arthroplasty is a word with a broader meaning than arthrodesis:

arthrodesis: the surgical fixation of a joint which is intended to result in bone fusion
arthroplasty: surgical reconstruction or replacement of a malformed or degenerated joint

arthrodesis (noun)	arthroplasty (noun)
the surgical fixation of a joint which is intended to result in bone fusion	surgical reconstruction or replacement of a malformed or degenerated joint