Penis pumps and vacuums are popularly used as sexual aids to promote erections in men. They are also used by some with the intent of increasing penis size. These devices are placed over the penis (and sometimes the scrotum) and use suction to engorge the penis with blood. If used consistently over a long period of time, they can cause the skin of the penis to become "spongy" and have a thicker appearance.
Contrary to popular belief, your penis is not a muscle, nor does it contain a bone. It's better to think of it as a kind of sponge, which, when flaccid, is soft and malleable, but can quickly become engorged when filled with blood. Two large cylindrical chambers, the corpus cavernosum and the corpus spongiosum (see?), fill with blood during arousal, causing your penis to harden and grow in size.
Yes, it can, but surgery is always associated with risks, including anesthesia, wound healing deficits, pain from scars, worst case even a deformed penis or permanent erectile problems. It’s effective without a doubt from our experience, but the last resort in our opinion. For men with a real micropenis (smaller than 2.75 inch) it’s often the only solution and covered by health insurance, but only about 0.5% of all men worldwide suffer from this condition. If you are just a bit below average, the risk versus reward calculation is negative for surgical penis enlargement. Especially one problem that arises from cutting the ligaments, the erection pointing slightly downwards instead of straight forward, can become a real problem according to professor Kevan Wylie from the NHS, he said “It can make sex quite uncomfortable. You’ve got to do a lot more manoeuvring with your partner. The advantage of a 2cm (0,8 inch) gain in flaccid length is far outweighed by the loss of angle of erection.”
The vacuum pump. This is a cylinder that sucks out air. You stick your penis in and the resulting vacuum draws extra blood into it, making it erect and a little bigger. You then clamp off the penis with a tight ring -- like a tourniquet -- to keep the blood from leaking back into your body. What are the drawbacks? The effect only lasts as long as you have the ring on. Using it for more than 20 to 30 minutes can cause tissue damage. This is sometimes used as a treatment for erectile dysfunction, but has not been proven to actually increase the size of the penis.