Has any other surgeon ever sutured onto the cartilage onto ribs to correct symmastia? (Photos)

The key to fixing symmastia is to close of the pocket.  But the "back wall" often has very thin and weak tissue on top of the rib cartilage.  Sometimes the only way to get a good bite is to sew into the cartilage.  That is nothing for you to be concerned about. 

hello ajoe_90  This is a condition which can occur when the implants are too close
together. Patients often refer to this as a “uniboob.” This can occur
for the same reasons as displacement noted above, but in this case the
pocket(s) is/are too far towards the center.
Correction of this problem may involve using different implants such
as textured, a smaller size, or a smaller base and placing the implants
in a new pocket. On occasion, this may require surgery in more than one
stage to allow the tissues to heal and then place the implants. If the
implants have been placed above the muscle, converting them under the
muscle frequently will help and, again, the use of a dermal substitute
may be required for additional support if the tissues are thin. The
techniques of capsulorrhaphy and neopectoral pockets may apply here as
well.