Whether this is malpractice cannot be determined from an online description, and that part is a legal question. Medically, a protruding bulge one year after abdominoplasty can have several causes, including recurrent muscle separation, an abdominal wall hernia, residual or recurrent fat, scar tissue, a seroma, or a contour irregularity. The first step is an in-person exam by your surgeon or another qualified plastic surgeon. If the bulge changes with standing, coughing, or straining, imaging such as an ultrasound or CT scan may be needed to check the abdominal wall. Ask for a clear explanation of what was repaired during your original surgery, what is being seen now, and what treatment options exist. Seek urgent care if the bulge becomes very painful, hard and non-reducible, rapidly enlarges, or is associated with vomiting, fever, redness, or bowel symptoms. If after a medical evaluation you still believe negligence may have occurred, you can discuss the legal question with a qualified malpractice attorney in your state, but the medical workup should come first.