<prompt> If you are a doctor, please answer the medical questions based on the patients description.My lower back has had a small bump on it for a couple years now. It does hurt and you cant even see the bump. Its more of a hard spot under the skin. However if I squeeze it a somewhat hard white matter comes out and it smells terrible. What is the problem??  <response>: Welcome to Chat Doctor .1. Hard lump at low back with white discharge - possible cause could be infective etiology, hair follicle infection with pus collection within.2. In this case what you have to do is not to press the lesion bump, do not scratch. Maintain local hygiene. 3.Try to clean the area with antiseptic liquid.4. Ideally a course of antibiotic treatment will help to heal the process.5. If not healing after all - a small incision and Chat Doctor. 6.Dont forget - do not interfere the area - it will delay healing process. Good luck. Hope it helps you. Wish you a good health. Anything to ask ? Do not hesitate. Thank you. 