A prior history of Sculptra or other buttock/body injections with lumps lasting for years is an important detail before considering a BBL. It does not automatically mean you can never have fat transfer, but it does mean the area should be examined carefully by an experienced plastic surgeon before any plan is made. Lumps after biostimulatory injections can represent product deposits, inflammatory nodules, scar tissue, or uneven collagen formation. If fat is grafted into an area that already has nodules or fibrosis, the final contour may be less predictable and there may be a higher chance of persistent irregularity, firmness, or asymmetry. In some cases, imaging such as ultrasound can be useful to understand where the lumps are and whether there is significant scarring. For BBL safety, the surgeon also needs to assess whether you have enough donor fat, your skin quality, your general health, and the condition of the buttock tissues. Fat should be placed only in the subcutaneous layer, not into the muscle, and the operation should be done in an accredited setting with a clear anesthesia and aftercare plan. Because your lumps lasted a long time, I would not treat this as a routine BBL consultation. Bring the exact product details if you have them, explain where the injections were placed, and have an in-person exam. If there are still firm areas or active inflammation, it may be better to treat or stabilize those first before considering fat grafting.