A breast reduction that extends to the side can definitely tighten. I tend to use a wise pattern which can be extend to the side for this purpose. What also can be done is to perform liposuction on the side in conjunction with breast reduction to reduce the volume on the side extending to the back.
Breast reduction operations relieve neck and back pain in many patients as well as lifting and reducing the size of the breasts. I also treat many of my patients with liposuction on the side of their chest and back. Occasionally I even excise excess skin along the bra line to contour the torso. Patients seem to be very pleased with the results.