Kathy Cregan no longer watches cups or plates slip from her weakened fingers or loses sleep from searing pain when she rolls over. She can trim a shrub, romp on the floor with her dogs and move her glance easily from desktop to computer screen.

Best of all, “both my boys can hug me now and it doesn’t hurt,” said Cregan, 42, whose neck is supported by five of her own discs — and one stainless steel one.

The Lincoln, Calif., accountant had been hurting since 1995, one of the millions of Americans plagued by neck or back pain.

Most improve with non-surgical help, such as physical therapy or steroid shots.

But hundreds of thousands, like Cregan, have been told their only alternatives are ongoing pain or fusion, an operation that removes one or more discs and freezes part of the normally mobile spine.

Surgeons are testing another option: implanting artificial discs to replace the damaged ones.

“This is a very, very important improvement in our field,” an evolution that may someday be seen as a revolution, said Dr. Kee Kim, chief of spinal neurosurgery at the University of California at Davis Medical Center.

Kim implanted three of the artificial discs in July, including Cregan’s, as part of a two-year study to compare the neck operation with fusion and see which delivers better mobility and pain control.

Several designs of manufactured neck and back discs have been implanted successfully, some for more than a decade, in Europe, Asia and Australia, but none has been approved for use in America.

That could change in late 2004 or early 2005, when the first of at least five discs undergoing U.S. evaluation could be approved by the Food and Drug Administration, said Dr. John Regan, medical director of the Institute for Spinal Disorders at Cedars-Sinai Hospital in Los Angeles.

The back, or lumbar, implants are further along, possibly because so many more people suffer from lower back pain, said Kim.

The neck, or cervical, disc that Kim is helping test probably won’t be FDA-approved until at least 2008 — if it performs well.

Even then, surgeons agree, it will be decades before real-world experiences show how well the discs last. If they win FDA approval, artificial discs could help people whose own discs have weakened in ways that put pressure on spinal nerves or the spinal chord, triggering pain in the lower back, neck or arms and sometimes numbness in arms and hands.