Left with extended butt crack after 360 tummy tuck - what needs to be done to have this fixed? (Photo)

Allow me to answer your question as best i can based upon one photo. However, please keep in mind that an in-person, or at least a virtual, consultation with physical exam is first necessary before any legitimate evaluation or final surgical recommendations can be made.

An elongated and/or flattened buttock is a common complaint after a 360° tummy tuck (a.k.a. lower body lift). Because fat survival is unpredictable and often poor is cases like yours, I personally treat patients like you by restoring volume to the buttock with a buttock implant. This will create a more desirable smooth and rounded perky buttock profile. By adding projection and a third dimension to the buttock, it helps the butt crack appear shorter. If beneficial, a lower buttock tuck can also then be performed at six months following implants. In this sequence, the implants have fully settled into final position so that any remaining loose skin can be most accurately identified and removed with the lower buttock tuck. Please note, because an extremely few number of board certified plastic surgeons specialize in buttock implants, you may have to travel away from your local area to seek consultation with this particular type of surgeon. Getting it done right the first time around is not only the best chance for success, but also will save you a lot of headaches and money in the future. Glad to help.

Unfortunately, the "Extended Butt Crack" does sometimes occur with lower body lifts or circumferential tummy tucks. The reason is.... When people are overweight, their skin gets stretched both horizontally and vertically. Tummy tucks and body lifts tighten the skin in the vertical direction by pulling the skin down and removing the excess skin. Unfortunately, these procedures do not address the horizontal laxity. That is why we sometimes do a vertical scar on the abdomen, the sides or above the buttocks crease to get rid of the fold of excess skin. So, this can be corrected, but this does require a vertical scar beginning between your buttock cheeks and extending up your back to where the crease stops.

To make a quality assessment regarding the outcome of any plastic surgery procedure we usually need to see a complete set of proper before and after pictures grand
Your picture is insufficient to make a good assessment.
Your scar looks quite low on the backside.
What did the before and after pictures of other patients outcomes look like when you had the consultation.
Consider reposting with better pictures.
Best,
Mats Hagstrom MD