The waiting room in William Yule's office is full by the time he arrives each morning.

Throughout the day, Yule sees dozens of patients, bouncing between four sparsely decorated examining rooms on such a tight schedule he often has no time for lunch.

But Yule is no doctor. He's a prosthetist who fits limbs on amputees, and business is booming for one reason: diabetes.

"There's no such thing as a slow day," says Yule, of Hanger Prosthetics & Orthotics Inc. in Downey, Calif., as he helps a client adjust her new right leg. "It can be hard, because you can't help thinking a lot of these people don't need to be here."

As 1.5 million Americans are diagnosed with diabetes each year, a growing number are confronting one of the most brutal consequences of the disease: amputation of a limb.

The number of amputees in the United States has grown by nearly 1 million over the past decade, according to federal statistics, and roughly 60 percent of amputations are diabetes-related.

Public health experts are ramping up efforts nationwide to reverse the trend, but for now there is a boom in the long-sleepy prosthetics industry, which experts say hasn't seen a sales spike like this since its modern inception, on Civil War battlefields.

Sales of prosthetics have jumped from $340 million in 1996 to nearly $600 million last year, according to estimates based on federal data.

The industry's growing profile has even caught Hollywood's eye. The Discovery Channel aired a 10-part series on a Fairfax, Va., prosthetics shop, "Rebuilt: The Human Body Shop," last year and a prosthetist was prominently featured in the first season of Showtime's "Dexter."

Although the industry has begun to consolidate, most manufacturers and sellers remain small to medium-size companies and mom-and-pop shops that are adapting to their growing businesses one step at a time.

Five years ago, Life-Like Prosthetics, a clinic in Torrance, Calif., that creates artificial limbs, saw two to three patients a day. Now it fits an average of eight patients daily, manager Carlos Sambrano said.

Sambrano, who sold the shop to a larger San Diego company last fall, said up to 70 percent of his clientele was now made up of diabetics, as opposed to one-quarter when he entered the business three decades ago, when most amputations resulted from car accidents or cancer.

The company moved into a 6,000-square-foot warehouse in 2004, doubling its size, and its biggest struggle today is finding qualified employees. "I've been looking to fill one of my spots since October," Sambrano said.

Peter Rosenstein, executive director of the American Academy of Orthotists and Prosthetists, said the industry's labor shortage worsened in recent years. By some estimates, it will need 100 percent more workers over the next decade.

Since 2003, Congress has given the organization $4 million in grants to heighten awareness of the specialty at high-school and junior-college job fairs and for public-awareness campaigns set to start later this summer.

"We tell kids, 'you can make a good living doing this,' " Rosenstein said. "A lot of them think it's cool."

Diabetes is a metabolic disease in which the body doesn't produce enough insulin or doesn't process it well. Because diabetics have reduced circulation in their limbs, an estimated 5 of every 1,000 diabetics eventually requires an amputation, usually of a leg. Up to half of the amputees lose two limbs.

To capitalize on the market boom, manufacturers are introducing an unprecedented number of artificial sockets and limbs, many aimed at older and overweight users rather than the younger patients who traditionally have been the focus for new products.

Some have sensors in the feet that clock how fast a user is moving, how much they weigh and if the foot is on an incline so it can adjust accordingly. Other products, such as the C-Leg and a bionic knee called the Rheo, are so advanced that some amputees use them to run marathons.

Typically patients weighing more than 250 pounds have had a hard time getting prosthetics, but some newer models can accommodate patients up to 350 pounds.

Prices of artificial limbs typically range from $2,500 to $50,000, depending on how advanced they are. Currently, insurers pay for most products, although some have started to balk as the number of reimbursement claims has risen.

In response, three states have passed laws in the past two years requiring insurers to boost coverage. In total, six states now have such laws, and several others are considering similar measures.

"We joke that whenever they have a pill to cure diabetes we are all going to be out of business," said Eric Robinson, president of Fraser, Mich.-based College Park Industries, which recently introduced an advanced foot called the TruStep.