hi pal,
from you post I understand your patient is
* a 30-year-old male patient - young adult
* very active in his early 20's - fairly active
* limping for a few days/weeks - obvious injury
* a year ago noticed very minor pain - long history
* cycling 15 km each way - constant stress/strain
* worse when bent at 90 degrees - symptomatic now
* feel a small clunk extending in weight bearing - supportive signs
should the patient be reffered to have an MRI scan?
well, from my point of view and experience I would definitely state "yes".
the underlying cause should be ascertained and follow up treatment coz the patient is young and should enjoy a good quality of life.
cheers,
thomas