College student David Pfeiffer lived with a painful problem for 12 years. When he was seven, he broke his left leg. When it healed, it grew one-inch longer than his right.

"I was walking around with one leg longer than the other. It was causing back problems," Pfeiffer said.

Patients like Pfeiffer used to have to wear a painful external device for months. Pins pierced the skin and muscle to literally stretch the leg.

With the PRECICE limb lengthening system, a titanium rod with a magnetic motor is internally implanted in the patient’s leg bone. An external remote control activates the magnets inside and gradually pulls the bone apart.

Dr. John Herzenberg, a pediatric orthopedic surgeon at Sinai Hospital in Baltimore, is glad to see this new procedure.

"No longer do my patients have to be condemned to wear this bulky medieval torture device outside their leg. This is what we've been waiting my whole professional career," Herzenberg said.

After 25 days of treatment, Pfeiffer's leg grew one inch. Now he can stand tall without any pain holding him back.

The device is capable of lengthening up to three inches and can be used multiple times if needed.

If the patient's leg is too long, they can also reverse the effects by turning the magnets in the opposite direction, as long as the bone has not healed.

So far, Herzenberg has used the system on about 100 patients. He said people from all over the world have traveled to his center to have this procedure.

DOWNLOAD and VIEW research summary and an in-depth interview with the doctor