The hospital privately accept the patient's replacement femur head illegal?

Not illegal.

Surgery and other diagnostic and treatment process of discarded human tissue, organs and other medical waste, must be in accordance with the requirements of the medical waste disposal regulations by the specialized agencies for special treatment. It provides that medical and health institutions should be based on the principle of centralized disposal of medical waste in a timely manner to the centralized disposal of medical waste disposal unit.

Medical waste, refers to medical and health institutions in the medical treatment, prevention, health care and other related activities generated by the direct or indirect infectious, toxic and other hazardous waste. So the doctor and the hospital is normal in accordance with the provisions of the medical waste disposal, no violation of law, the family has no right to dispose of the replacement down the femoral head.