In January, Boon launched her own study to compare Botox to cortisone shots, a standard treatment for arthritis pain. "If this could actually block pain, it might be a great second-line treatment," she said.

A spokesman for the Arthritis Foundation called it a novel idea that's "definitely worth pursuing. "It probably is not going to change the natural history of the disease," said Dr. John Hardin, chief scientific officer for the Arthritis Foundation in Atlanta. "But it could be a very useful symptomatic treatment."

For now, Boon remains cautious.

"It seems to be a relatively safe treatment option, (but) to be fair, we don't have long-term data," she said. Even as a treatment for wrinkles, she said, "we don't know what will happen in their muscle in 20 years' time. That is a concern."

And anyone hoping for a two-fer will be disappointed. Botox in the knee joint won't spread to the face, Boon said. "It only works, affects wrinkles, if it's going in the muscle underlying the wrinkles."

---

Dist. by Scripps Howard News Service