Here's another one that's more serious than the road rash question: What are some good exercises to prevent knee pain?What are some good exercises to prevent knee pain?
Here you have a cyclist who injured his knee while riding. He had swelling and severe pain, and went so far as to take 6 months off from riding. There is no indication that he saw a physician. So now he's continuing to suffer pain and soreness, and asking for knee exercises because he's afraid that he'll hurt his knee again.
This strikes me as a red flag question. The poster in question accepted an answer that is essentially good; however, the answer primarily focuses on ITBS and stretches for that. If the poster does have ITBS, ok. But what if he actually has a lateral meniscus tear? Or one of a few other possibile injuries? The stretches and exercises recommended could make it worse, leading to surgery or maybe he already needs surgery. Or maybe the poster accepted the advice in the accepted answer to see a physician? Who knows?
There is a huge difference between the road rash question and the knee pain question. With the road rash, the cyclist received medical attention, had an accurate diagnosis and was seeking additional information/tips. The knee pain question is about an undiagnosed internal injury. So, are we to assume that this cyclist should accept the upvoted answer, head off to his gym, and exercise his injured knee?