Jack Lancaster nimbly climbed the freestanding rock wall on the lawn adjacent to an office building in Old Town Manassas.

Feeling for the next hand- and footholds, he was guided up the wall by professional climbing athlete and above-the-knee amputee Ronnie Dickson.

It took a second look to realize that the 5-year-old from Charlottesville was maneuvering up the wall using his left arm, which ends just below the elbow.

Jack, his 8-year-old sister Anna and their parents, Keith and Kristy Lancaster, attended Limb Loss Education Day on Sept. 29, which coincided with the opening of the Amputee Coalition’s new headquarters on Center Street in Manassas.

The rock wall, provided in partnership with the Orthotic and Prosthetic Activities Foundation, is one of the adaptive recreational programs sponsored by the coalition.

More than 80 people attended the ribbon-cutting ceremony and open house, coming from as far away as Florida, New Jersey and North Carolina.

Judy Wike, 46, drove from Westminster, Md., to attend the event. Before she lost her right leg in a shooting accident, Wike had wanted to try rock-wall climbing “with two good legs,” she said. Wearing a prosthetic, she gingerly moved up the face of the wall. The process was exhausting but encouraging, she said.

The Amputee Coalition is a national nonprofit organization that was founded more than 25 years ago in Knoxville as a support group for people with limb loss.

The organization has grown to offer a network of support groups. It also provides educational and outreach programs and acts as an advocate for the nearly 2 million Americans who have lost limbs.

The Lancasters found out that Jack’s arm ended below his elbow while Kristy was pregnant with him. “It was comforting to know that there was an organization already established that was committed to helping the limb-loss community,” she wrote in an e-mail.

The coalition, which retains a branch office in Knoxville, moved its headquarters to Manassas in part because of the large amputee population in the Washington metropolitan area, Amputee Coalition communications manager Mary Beth Gibson said. But the group also wanted to be in closer proximity to legislators.

“The coalition speaks on behalf of the limb-loss community at the federal level and in state legislatures nationwide,” said Marshall J. Cohen, chairman of the Amputee Coalition board of directors. “We lead a growing national movement to achieve insurance fairness for amputees and appropriate coverage of prosthetic care.”

The organization has worked to pass legislation in 20 states that supports fair coverage for prosthetics and orthotics, which can cost up to $50,000, Gibson said.

The Lancasters know all too well the cost of prosthetics. Their son has tried various devices that have proved cumbersome and ineffective. When their doctor recommended a myoelectric prosthetic, they were hopeful that it would help Jack with the thumb-finger pincer grip. The Lancasters’ health insurance, however, denied their claim stating that “it was not medically necessary,” Lancaster wrote. They turned to the Amputee Coalition for help with an appeal.

As for living without a limb, Lancaster wrote, “We are learning as we go; [Jack’s] an amazing kid with a strong willed personality that we know will take him wherever he wants to go in life.”