Dear Ask The Doctor:From what you have described it seems that you may have had a muscle tear/pull when you sustained the blunt trauma to your thighs. This could have been further aggravated when you went sledding, which is why the pain now seems more than usual. However the swelling of the left knee and slight bruising seems to concern me and I would advice you to go to your family physician for a more complete physical examination which would help diagnosing the problem and further determining the course of action.
In the mean time you could try some hot compress to the thighs and some anti inflamatory like advil which will help with the pain . Also local anti inflamatory gels like Voltaren may help if it is in fact a muscular injury.
Hello, 5 days ago I suffered blunt trauma to the middle of both of my thighs. Immediately following, my left thigh was swollen, and my right thigh slightly swollen and bruised. Walking was also very difficult and painful. For the next 2 days the swelling went down and the pain just felt like sore muscles after a hard work-out. 2 days ago I went sledding down a hill, and don't recall hurting it, however the past two days the pain is excruciating, keeping me up at night. There is only a small bruise on my left knee (not where i was hit)and minimal swelling. Any ideas why the pain? Also, should I get an x- ray? It's too early to tell, but I may be pregnant.