10 year old son had brief sharp pain in chest. Afterwards started to have pain in right leg below knee. He says it is better when rests for a period.

Not likely serious. A 10 year old with a brief chest pain and a pain afterward in the right leg below the knee is not likely to have anything serious like a blood clot traveling to the lung unless he has been at bed rest or immobilized for several days or had recent surgery.**But if he's still having leg pain and points to his calf, or if he's significantly more tender in that calf than the other>go to ER to be safe.

Related Questions

My 10 year old son had a short sharp pain in his chest that lasted about 30 sec and afterwards is complaining of pain in his right leg below the knee.

Short Answer...... Go to your doctor for further evaluation. Too many possibilities to discuss in this space. Many not serious but still need to be clarified. Read more...
Can't relate them. Brief chest pains in kids are most often heartburn while leg pain is most often related to overuse.I can not think of any condition that would pair the two together.You provided so little info that not much more can be said. A more thorough history and exam could eliminate the scary things.In the future please submit as much info as you can and a concice question. Read more...