Penis enlargement (girth) surgery---
A related method involves injection of silicone, PMMA, and other materials into the penis and scrotum, to achieve girth enlargement. The results of the study into penile augmentation surgery mentioned above confirm that surgical techniques used to thicken the penis are far more effective than those designed to increase penile length.
Penis enlargement (length) surgery---
Penis lengthening involves the release of the fundiform ligament and the suspensory ligament that attaches the two erectile bodies to the pubic bone. The suspensory ligament makes the penis arch under the pubic bone. Release of this ligament allows the penis to protrude on a straighter path, further outward to give more functional length. With the penis on stretch, the ligament is divided close to the pubic bone until all midline attachments have been freed. Once these ligaments have been cut, part of the penile shaft (usually held within the body) drops forward and extends out, enlarging the penis by 20-30 mm (0.78-1.18 in.).
A further method is to replace the two corpora cavernosa with inflatable penile implants. This is performed primarily as a therapeutic surgery for men suffering from complete impotence; an implanted pump in the groin or scrotum can be manipulated by hand to fill these cylinders from an implanted reservoir in order to achieve an erection.