1. a wrinkled shirt
2. a rumpled shirt
These two mean the same thing, don't they?
They mean basically the same thing.
To my ear 'rumpled' has the connotation of being creased and disordered through wear. ('He had a rumpled look after spending a sleepless night on the train.')
'Wrinkled,' on the other hand, means creased in an untidy way.
Also, skin can be wrinkled, but not rumpled.
I hope this is helpful,