Possible problems with implants include mechanical breakdown and infection. Mechanical problems have diminished in recent years because of technological advances. Malleable implants usually consist of paired rods, which are inserted surgically into the corpora cavernosa, the twin chambers running the length of the penis. The user manually adjusts the position of the penis and, therefore, the rods. Adjustment does not affect the width or length of the penis.
Tubes connect the cylinders to a fluid reservoir and pump, which also are surgically implanted.
The patient inflates the cylinders by pressing on the small pump, located under the skin in the scrotum. Inflatable implants can expand the length and width of the penis somewhat. They also leave the penis in a more natural state when not inflated. Surgery to repair arteries can reduce impotence caused by obstructions that block the flow of blood to the penis. The best candidates for such surgery are young men with discrete blockage of an artery because of an injury to the crotch area or fracture of the pelvis.