AUGUSTA — Kevin Carroll held the door patiently — gladly, even — and launched into a steady stream of encouraging words.

The old man shuffled toward the door, using a walker and on two prosthetic legs, as though closing in on the finish-line tape at the Boston Marathon.

“Fabulous,” Carroll said as the man crossed the threshold.

Carroll closed the door and turned, his face creased with a smile and lit with the joy of seeing a person moving on with life.

“That’s the power of the human spirit,” Carroll said.

After more than 30 years as a practicing prosthetist, Carroll said he still finds joy in restoring mobility and independence to those who have lost a limb or limbs from disease or trauma.

On Wednesday, Carroll, vice president of prosthetics for Hanger Prosthetics and Orthotics, was at the company’s Augusta location to meet amputees and talk about the latest in prosthetics technologies.

“Life is not over when they lose their leg,” Carroll said. “It’s just the beginning and they’re ready to take on the world.

“There are great things happening,” he said.

That progress includes a new gel sleeve Carroll created while developing a prosthetic for Winter, a bottlenose dolphin that got caught in crab traps off Cape Canaveral, Fla., in 2005 .

Winter was freed by a fisherman and taken to the Clearwater Marine Aquarium in Carroll’s home state of Florida. The dolphin recovered from her injuries, but her tail was badly damaged and eventually fell off.

Without the fluke — the broad, flat portion of at the end of the tail — to give her thrust through the water, Winter started to slap what remained her of tail side to side like a shark, which threatened to injure her back.

Carroll got involved in the case in 2006 in hopes of developing a prosthetic fluke. The process took about a year and half.

Winter’s story will be told in movie called “Dolphin Tale” starring Morgan Freeman, Ashley Judd and Harry Connick Jr., scheduled for release in the fall.

One of the challenges Carroll faced was Winter’s delicate skin. The gel Carroll developed to protect the skin has proven useful on human beings, particularly soldiers who have lost limbs to blast injuries. The shattered bones left by the blast can leave jagged edges that create discomfort in the joint between the remaining leg and the prosthetic fitting.

“The gel absorbs the force and makes it more comfortable,” Carroll said.

Chad Thompson, who lost a portion of his leg during a hunting accident in 1992, said the most important part of a prosthetic is how the leg feels.

“I think it’s a lot better for my skin,” Thompson said of the gel.

Thompson first met Carroll as a patient after his injury.

Now, they are colleagues. Thompson is a peer advocate for Hanger — a national company that offers health care products and services — where he helps patients adjust mentally and socially to life without a limb and with a prosthetic.

“I feel like I’m mentoring them,” Thompson said. “That is a powerful thing for me.”

Carroll’s gains in prosthetic technology have made Thompson’s job easier.

“The technologies make me more positive about the outcome,” he said. “It’s really fun to be a part of it.”

Craig Crosby — 621-5642

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