Most changes in body shape relate to the skin, the adipose tissue (the fat layer) and the muscles.
Skin folds develop as the skin becomes more flaccid with age. The fat layer becomes thicker by fat accumulation, but also by congestion with tissue fluid as the lymphatic circulation slows down. As the skin and the connective tissue in the fat lose their elasticity, the skin and the fat layer sag with respect to the muscles and the bones.
Muscles lose some strength. This changes the posture (e.g. increased curvature of the lower back). Connections between muscles may stretch and allow bulging of deeper tissues (e.g. vertically orientated bulge on the midline of the abdomen after pregnancy).
Good dietary habits and a good physical condition are essential for a nice body shape.
If the problem consists mainly of localised, excessive fat deposits, liposculpture (liposuction) may be useful. After liposculpture, the skin can shrink within certain limits.
Sometimes tissue sagging is so important that skin folds need to be surgically removed to obtain proper correction. Sometimes a liposculpture is performed first and the skin is left to shrink maximally. If skin folds persist, they are removed in a second operation.
Otherwise, it may be clear from the beginning that surgical lifting is necessary. The main causes are normal ageing above the age of sixty, stretching of the skin by pregnancy and important loss of weight.
The inevitable scars of lifting procedures are the trade-off for dramatic body contour improvement. The sutures may be placed under the skin to obtain a linear scar (as opposed to the "zipper"-like effect of conventional stitching).
Almost always a hospital stay of one ore more nights is necessary. In large operations suction drains are left in place. These thin plastic tubes evacuate the blood that oozes into the wound the first hours after the operation. This way, excessive bruising is avoided. Sutures generally stay in for two weeks.
A "body lift" or "torsoplasty" is a combination of open surgery and liposculpture of several parts of the body.
Click on the links for more detailed information.