The wail of sirens filled the streets as ambulances rushed to the victims of the Boston Marathon bombing on Monday.

For several of the more than 170 runners and spectators injured, lost limbs mean their bodies will never be the same.

There are a handful of people in Boston who woke up this morning for the first time facing their new reality -- life as an amputee.

"It kind of brings me back to when I had my accident and thinking of all the challenges that I had in front of me, just the different path that their life is going to take them," said double-amputee Francis Manning.

Manning can't help but have flashbacks to the fateful day that changed his life decades ago.

When he was 18, both legs were mangled when he tried to jump on a moving train.

"I missed," said Manning.

Now he devotes his life to helping others who've lost limbs by building prosthetics and mentoring fellow amputees.

He said the road ahead for those maimed by the Boston Marathon bombs is a rocky one.

"It's just a life-changing event," said Manning. "They're going to have to learn how to walk again if they're missing a limb."

"You're always thinking function. 'How do I get this person moving?'" said Bill Haviland, a physical therapist at Gundersen Lutheran.

One of the first steps for some amputees is recovering from phantom-limb syndrome -- feeling pain in a limb that isn't there anymore.

"All pain is perceived through the brain. So just because you remove a portion of the person doesn't mean that the area that was designated for that part of the brain isn't still there," said Haviland.

Manning said going through anger and depression are common, too, but determination is the key to moving forward.

"You have to come to the stage where you're accepting that this is who you are now -- you have a different path you're taking, a different journey -- and just be determined to do it," said Manning.

Haviland said prosthetics aren't for everyone. There are a lot of risks and work that go into wearing one. Plus, amputees typically can't get into prosthetics right away because their wounds have a lot of healing to do before they can be fit for one.

Manning spent a year in a wheelchair before his legs healed enough to make prosthetics a possibility.

April is Limb Loss Awareness Month. More than 2 million Americans are currently living with limb loss.