Why does my under the muscle silicone breast implant stick out this way? (photos)

Hello, in my opinion there could there several reasons given your more complex operative history. However, one common reason is the implant "flipped" inside of the pocket. Instead of the round part facing forward, the flat part is now facing forward. Ultimately, I would advise a physical exam and potentially an ultrasound by a board certified plastic surgeon who will be able to come up with a plan to help you!

The history of tuberous breast is the likely underlying problem. If the constricting ring of fascia (that is part of tuberous breast) is not adequately released, it will persistent and prevent the implant from sitting correctly in the pocket. You may require a revision surgery to release those bands of fascia. I would recommend seeing a board-certified or board-eligible plastic surgeon with aesthetic surgery training and experience to tackle this type of problem in a safe and efficient manner. Best of luck!

From your photos it appears your implants are too large and are sitting too high currently. A revision with smaller implants and potentially a lower profile should give you a more natural appearance. See a board certified plastic surgeon near you for a consultation.