U.S. Rep. Tammy Duckworth still remembers the anger she felt when well-wishers offered encouragement after she lost both legs when her helicopter was shot down over Iraq in 2004.

“I thought, how the heck is my life ever going to get back to normal?” the Illinois Democrat recalled.

Duckworth spent a year recovering and many more adapting to her new life. “Recovery is not a smooth process,” she said. “You are trying to process what happened. Your family is going through shock. … You have to find a new normal.”

But Duckworth did, thanks in part to major medical and therapeutic advances. She has run in three marathons, earned a new pilot’s license and, last year, won a seat in Congress. “I have done things I never dreamed of doing,” she said.

The victims of Monday’s Boston bombings now face similar challenges; at least 13 confront futures with lost or maimed limbs. Their recoveries will be long and arduous, experts say.

For many of the injured, even those who have health insurance, the process may also be costly. Health insurance plans often restrict coverage for therapy and prosthetics.

But a decade of wars has helped fuel breakthroughs that could help many Boston victims — including those with amputated limbs — live full, active lives.

“The world becomes a very different place when you lose a limb,” said Karen Mattie, rehabilitation director at Boston Medical Center, one of several hospitals caring for people injured in the bombings. “But the beautiful thing is that prosthetics can help people regain an amazing amount of function.”

At the end of the week, several dozen bomb victims remained in hospitals, including two who lost more than one limb.

Those with missing or damaged limbs could face more surgeries in the coming days and weeks as doctors clean wounds to prevent infection and repair damaged muscles, blood vessels and other tissue.

“It’s not as simple as just sewing up a wound,” said Dr. Carl J. Hauser, a trauma surgeon at Beth Israel Deaconess Medical Center in Boston. He also noted that many of the injured experienced shock and lost significant amounts of blood, which can complicate recovery.

Once rehabilitation begins, many patients will confront the frustrations of adapting to life without a foot or a leg. Depression is common.

“They also have to try to process what their life is going to be like now,” said Dr. Paul F. Pasquina, who headed the rehabilitation program at Walter Reed National Military Medical Center for much of the last decade. “That can weigh greatly on one’s emotional well-being.”

About a third of adults who have traumatic injuries will suffer from some form of prolonged stress disorder, according to Dr. David X. Cifu, director of the Veterans Health Administration’s physical medicine and rehabilitation program, which has dealt extensively with the long-term effects of trauma.

Paying for care can add to the strain.

Unlike soldiers and Marines injured in Iraq and Afghanistan, who have access to the latest prosthetics and extensive rehabilitation programs at Walter Reed and elsewhere, the Boston victims will not be guaranteed coverage for all their medical care.

Health insurance plans often cap how much they will pay for prosthetics, which can cost tens of thousands of dollars depending on the complexity of the device. Insurers also frequently limit the number of rehabilitation visits they will cover.

Twenty states have laws barring dollar limits on prosthetics, according to the Amputee Coalition, a national advocacy group that has been fighting to ban the limits. But such limits are still permitted in most states and in many employer-sponsored plans that are exempt from state regulations.

“There is really no reason every American amputee shouldn’t be fully functional, except health insurance isn’t willing to pay for it,” said Dan Berschinski, a former Army captain who lost his legs in Afghanistan in 2009 and now serves on the Amputee Coalition board.

“I have never seen a medical bill … and I have a Ferrari’s worth of legs in my closet,” he said. “Most civilians can’t even get those legs.”

Families and friends of the injured in Boston are already setting up funds to help defray medical bills.

Liz Harlan, a Maryland preschool owner whose friend Erika Brannock lost her left leg and seriously injured her right in the blast, is helping raise money so Brannock can remain on her health plan, which she is scheduled to lose when her teaching job ends in June. “We don’t know how soon Erika is going to be able to work,” she said.

Beginning in January, people like Brannock will have at least one new protection. A provision in the 2010 Affordable Care Act will bar insurers from denying coverage to people with amputated limbs or other preexisting medical conditions, although it will not ensure coverage for all medical expenses.

Nationwide, about 2 million people have either had a limb amputated or were born with abnormalities in their limbs, according to the Amputee Coalition.

The victims of the Boston bombings will also likely benefit from advances in medical technology. New lightweight prosthetics with motors and complex gyroscopes allow patients with even the most severe amputations to walk, and even run.

And a better understanding of how to intervene quickly with peer counseling and other therapies can speed recovery and mitigate the depression many will confront.

“Very often, one of the best therapies is getting them back to doing what they are doing,” said Cifu of the Veterans Health Administration. “They go from being someone with a disability to someone with a real ability.”