broken vs broken in

broken and broken in both are adjectives.

Word	Noun	Adjective	Verb	Adverb
broken	No	Yes	No	No
broken in	No	Yes	No	No

As adjectives, broken and broken in are synonyms defined as:

broken (adjective)	broken in (adjective)
physically and forcibly separated into pieces or cracked or split	tamed or trained to obey
not continuous in space, time, or sequence or varying abruptly
(especially of promises or contracts) having been violated or disregarded
out of working order (`busted' is an informal substitute for `broken')
destroyed financially
thrown into a state of disarray or confusion
discontinuous
subdued or brought low in condition or status
weakened and infirm
imperfectly spoken or written
lacking a part or parts
topographically very uneven
tamed or trained to obey