Is this osteochondroma?

Patient: My son has a hard, moveable lumb about 1 inch above his knee. The lump is about .5 inches in diameter. He says it doesn’t cause pain, but the knee it is on feels more stiff and sore when running. Also, he says that sometimes that leg goes partly numb when running. Is this osteochondroma and would you suggest removal? If I need surgery, what kind of recovery can be expexted (crutches, activity restraints, etc.)? My son is a 15 year old male. He is 6′ tall and faily skinny. He also has type one diabetes.