CHARLOTTE, N.C. (AP) _ Barbie, the doll with the drop-dead figure and more lives than a whole family of cats, is now doing her part for medical science.

In her 40 years, Barbie has had more than 75 careers, ranging from astronaut to paleontologist. Now, she's become a medical assistant _ of sorts.

It turns out the plastic knee joints in Barbie's long legs make good knuckles in prosthetic fingers.

Jane Bahor, who makes lifelike body parts for amputees at Duke University Medical Center in Durham, has used knees from retired Barbie dolls to make new fingers for about a dozen patients.

``She's made her cultural contribution, now she can make a medical contribution,'' Bahor said of Mattel's popular doll.

Bahor and a patient, Jennifer Jordan, then a North Carolina State University engineering student, came up with the idea three years ago while discussing how to make Jordan's prosthetic finger more realistic and useful.

Last fall, when Bahor thought the idea was really going to work, she called Mattel and asked to buy some knee joints. Mattel was so impressed that it sent Bahor a bag full of parts _ free.

Wearers of the fake fingers bend them in the same way they would bend Barbie's leg. They can use their other hand to bend the joint, as if cracking the knuckle. Just like Barbie's legs, the fingers stay bent until the owner straightens them.

Being able to bend prosthetic fingers makes it easier for an amputee to hold a pen, pick up a cup or grip the steering wheel.

``Just a simple thing like that is an enhancement,'' Bahor said.