When John DiMasso lost his left leg in a motorcycle crash that killed his wife, his insurance company paid generously for the amputation surgery and rehabilitation that would get him back on his feet.

Three years later, DiMasso needs an expensive replacement part to allow him to walk comfortably on his artificial leg.

But his employer has changed its insurance carrier and the new one, Healthnet of the Northeast, has stricter limits on how much it will pay to restore and replace the artificial limb.

As a result, DiMasso, 46, of Southington, was limping and uncomfortable Thursday when he joined about two dozen other amputees on the steps of the state Capitol in Hartford for a rally demanding better health insurance coverage for prosthetics.

The rally was part of a multi-state effort by advocates for amputees to force insurance companies to pay the full cost of fitting and maintaining prosthetics. So far, seven states have passed laws requiring insurance companies to cover prosthetics. The advocates are also seeking federal legislation requiring prosthetic coverage.

Without such a requirement, amputees are often forced to hold fundraisers, dig into retirement savings or go without other necessities so they can afford artificial limbs, said Morgan Sheets, an organizer with the Amputee Coalition of America.

"I have calls every week from people wanting to set up a fundraiser, a cocktail party, a bake sale," Sheets told a small group of amputees and supporters in Hartford Thursday. "It seems absurd that somebody who needs a heart bypass would have to organize a fundraiser to pay for that care."

Alice Ferreira, a spokeswoman for Healthnet, said the problem with mandating insurance companies to cover the full cost is that it will simply raise the cost of health insurance for businesses and individuals.

"How do we strike a balance of providing this level of coverage while maintaining affordability?" Ferreira asked.

Insurance coverage for prosthetics varies widely from one company to another. The only consistent thing, Sheets and others said, is that coverage seems to be eroding.

Ulli Delmar, 58, of Stamford, lost her right leg more than three years ago, when a driver ran a stop sign and smashed into Delmar's car as she drove along Route 1. In one year, she and her husband paid $55,000 in out-of-pocket costs related to her artificial leg. Anthem, her insurance company, covered the rest. To pay the bills, the Delmars have been dipping into their retirement savings, something Ulli Delmar resents.

"I've paid [for insurance] for all these years, now I need help and I have to fight and fight and fight," Delmar said.

Patty Stochmal of Derby pays about $4,000 a year to replace her daughter Lauren's left leg to keep up with the 3-year-old's rapid growth. Lauren lost her limb as a baby, following a viral infection.

Stochmal is covered by CIGNA through her husband's employer, Sikorsky Aircraft, and the insurance pays about 60 percent of the family's prosthetic costs. The Stochmals have also accepted contributions from fundraisers and a charitable foundation to help cover their share of the costs.

But as Lauren gets older, the cost of her replacement legs will go up, increasing the burden on her parents.

The co-chairmen of the General Assembly's insurance and real estate committee said they are sympathetic to the plight of the amputees. State Sen. Joseph Crisco, D-Woodbridge, and Rep. Brian O'Connor, D-Clinton, said they would consider legislation mandating full coverage for prosthetics in the upcoming legislative session.

But O'Connor said he wants to be sure the cost of such a mandate does not further inflate the cost of doing business in Connecticut.

"We'll weigh the body of evidence," O'Connor said. "We want to make sure people can get the equipment they need and weigh the costs and benefits of everything."

John DiMasso said he unwittingly contributed to his own problem when, at the recommendation of his doctor, he went on a diet and lost 35 pounds. It was probably good for his blood pressure and cholesterol levels, but slimming down meant the socket that attaches his artificial leg to his body no longer fit snugly.About the same time, his employer switched from Aetna to Healthnet as its insurance carrier. While Aetna covered all of his costs, the Healthnet policy included a $5,000 lifetime limit on all of DiMasso's prosthetic needs.

Ferreira confirmed that most Healthnet plans carry a $5,000 lifetime limit on prosthetics, although employers can opt to pay more for plans that offer more generous coverage.

The problem for DiMasso is that the cost of the new socket alone is more than $5,000, meaning if he used his insurance coverage he wouldn't have anything left for future coverage of more expensive needs, such as a replacement leg.

Instead of buying a new socket, DiMasso tried to gain a few pounds. But the weight went straight to his belly, eluding his leg. DiMasso said the ill-fitting socket is putting pressure on his bones, making it uncomfortable for him to walk.

But he said he has little choice.

"If I could afford it," DiMasso said of the replacement socket, "I would have done it already."

Contact Hilary Waldman at hwaldman@courant.com.