<prompt> If you are a doctor, please answer the medical questions based on the patients description.Hey I noticed a lump on my 5 year old son on the back of his leg last week. He said he fell at school the day before so I took him to the doctor and said it was a hematoma, but I talked to my friend and she said she noticed it on him about a week and half ago when I saw her. Should I take him back to the doctor again?  <response>: Hello dear, warm welcome to Chat Doctor.come have evaluated your query thoroughly. This is in relation with trauma giving rise to accumulation of blood in the subcutaneous space of the area and hematoma formation. Get recovered with ice application, necessary antibiotics and anti-inflammatory molecules for its resolution ; surgical intervention in some cases. Hope this will help you for sure. Wishing him fine recovery. Regards. 