Is it common or possible for a Tummy Tuck scar to stretch? (photo)

Yes it is possible for tummy tuck scars to stretch.  They are under significantly more tension than a C-section scar for example.  The photo above demonstrates a wide scars and "track marks" which can both be minimized with good technique.  Most plastic surgeons do not place sutures through the skin on tummy tucks that have to be removed as would be indicated by the photograph.  Regardless keep in mind that the improvements in shape/contour are at the expense of having a long scar.  If scar is not healing well there are many modalities that can be employed to treat the particular scar condition.  Best of luck

Any scars can stretch especially if they are under tension.  To help with that, your surgeon can use taping and silicone sheeting.  Also, typically patients remain hunched over for a few weeks after abdominoplasty so as not to put tension on the wound.