What about if I am poor and have no $$? Isn't it free if I go to government hospitals in HK and the Xray is free too?!? I don't know the HK healthcare system anymore.
If it is free, you should go to the hospital's emergency department and complain about the knee pain and discomfort. The doctor in ED should order an xray for you.
Xray only shows the bones though. If it involves soft tissues, you need a CAT scan (電腦掃描) to confirm.
If is 骨裂 you should know because it should be very very painful right? That's what my teammate told me. She was running and she has this intense pain... it turns out her bone is 骨裂