I do have it and it's not good at all. Depending on how you got OSD will help you seek how much pain will be involved. I got mine in my right knee by making an accidental slide. The swelling was extremely painful. I'm not sure the name of the bone, but I think it was my tibia, and it was and still is sticking out my knee 1 1/2 inches because of servere swelling near my growth plate. Make sure go to the doctors and get his knee x-rayed ammediaty by a doctor. It could only be a small injury but better safe than sorry. If your son's symptoms are normal than he should have trouble running for an extended period of time. Another problem is the bump on his knee will be there years and years or the rest of his life if it is servere. The best thing to do is just get a brace ar pad to protect his knee for awile and as the pain starts going away it'll be fine.
Do not take OSD lightly!!! 
I do have it and it's not good at all. Depending on how you got OSD will help you seek how much pain will be involved. I got mine in my right knee by making an accidental slide. The swelling was extremely painful. I'm not sure the name of the bone, but I think it was my tibia, and it was and still is sticking out my knee 1 1/2 inches because of servere swelling near my growth plate. Make sure go to the doctors and get his knee x-rayed ammediaty by a doctor. It could only be a small injury but better safe than sorry. If your son's symptoms are normal than he should have trouble running for an extended period of time. Another problem is the bump on his knee will be there years and years or the rest of his life if it is servere. The best thing to do is just get a brace ar pad to protect his knee for awile and as the pain starts going away it'll be fine.
I do have it and it's not good at all. Depending on how you got OSD will help you seek how much pain will be involved. I got mine in my right knee by making an accidental slide. The swelling was extremely painful. I'm not sure the name of the bone, but I think it was my tibia, and it was and still is sticking out my knee 1 1/2 inches because of servere swelling near my growth plate. Make sure go to the doctors and get his knee x-rayed ammediaty by a doctor. It could only be a small injury but better safe than sorry. If your son's symptoms are normal than he should have trouble running for an extended period of time. Another problem is the bump on his knee will be there years and years or the rest of his life if it is servere. The best thing to do is just get a brace ar pad to protect his knee for awile and as the pain starts going away it'll be fine.