Device acts like GPS during knee replacement

PHILADELPHIA (WPVI) -- Horses have always been Barbara Rosoff's passion.

"It's like breathing," Barbara says.

"I trained and boarded horses, taught lessons, I've worked with the handicapped," she continued.

She even founded a non-profit to introduce cancer patients to riding.

But when bad knees started to get in the way.

She had her right knee replaced, but it took 6 months to get back in the saddle.

"It was very difficult, VERY difficult," she recalls.

But, in January, Doctor David Nazarian replaced her left knee, and Barbara was riding again in just 10 weeks.

Doctor Nazarian believes one reason is because he used an electronic tool called Verasense.

He says that while replacement joints themselves are better than ever, up to 20% of people aren't happy with them.

"Probably because the ligaments aren't balanced," Dr. Nazarian says.

Ligaments help stabilize the knee.

But he says doctors have never had a good guides to check them during knee replacement operations.

"They would actually, in a primitive manner, jiggle the knee, and get a sense be feel to see whether the knee was appropriately balanced," he notes.

Now, as he prepares to put in the new joint, Dr. Nazarian puts Verasense into the space.

Pressure sensors embedded in it tell him how the implant should be adjusted, sending the data wirelessly to a monitor..

And once he gets it right, Verasense comes out, and the new joint is anchored in place.

Compared to her first knee replacement, Barbara says this recovery was a breeze.

Now, she can focus on her horses.

"I can now squat to do a horse's leg versus bend at the waist," she says, smiling.

There is a Verasense sensor for most major brands of knee implants.

Right now, Dr. Nazarian is one of 2 doctors in the Philadelphia/South Jersey/Delaware using Verasense.

The maker of Verasense says Dr. John Mariani of Reconstructive Orthopedics in South Jersey is the other.