TAMPA — It has to be a question that isn't asked often: Would the leg work better with the foot turned backward?
In an unusual experiment that University of South Florida scientists conducted Tuesday, that really was one of the choices they considered. Scientists evaluated how well different types of prosthetic limbs work for rock climbing by monitoring the efforts of a top athlete using various prosthetics.
Should the leg be full-size or shorter? Should the knee bend? Would the foot just get in the way?
Sometimes, it's easier to climb with no artificial limb at all, said Ronnie Dickson, 21, a Tampa resident who is one of the nation's best amputee rock climbers.
"Sometimes it's body tension, rather than strength," that helps him on a climb, Dickson said.
The study posed such questions partly for sport, but also for a more serious purpose: With the number of amputees increasing because of the war in Iraq, rock climbing is being used more often to help with rehabilitation, said physical therapist Jason Highsmith, a USF assistant professor.
Insurance pays for a normal walking prosthesis, but rarely for the shorter, unbending "stubby" limb that some climbers prefer. Such prosthetics can cost $6,000 to $7,000, Highsmith said.
He figures proof of what works best would help climbers get access to the best equipment.
"Is it beneficial or isn't it?" Highsmith said. "If it is, and it's getting the participants out in a lifetime sport, then they should have it."
While it might seem as if a life-like prosthetic would work best, many athletes find that a full-size limb that bends at the knee is actually a hindrance. Once the knee bends, it's hard for climbers to use the leg to push off the rock.
"It's designed for walking," Highsmith said. "It's not designed for climbing."
The study is part of the work on prosthetics at USF being funded with a $1-million grant from the U.S. Department of Education. Others also helped in Tuesday's experiment, from climbing gym Vertical Ventures, which donated gym space, to four prosthetics companies.
On Tuesday, Dickson climbed walls for science. Four times, he strapped on a prosthetic limb with a different configuration. The fifth, he climbed bare.
Each time, scientists timed Dickson's performance. He climbed with oxygen sensors strapped over his mouth, so that scientists also could measure which climb took the most effort.
Dickson climbed each way three times and rested in between, so that tiredness wouldn't skew the results.
Later this week, Dickson will travel to Michigan to compete against other athletes who have lost a limb in the O&P Extremity Games. The competition includes everything from skateboarding to kayaking to BMX riding. Dickson will compete in two rock-climbing events.
Dickson's left leg was amputated above the knee three years ago because a congenital disease and subsequent complications left him with a locked joint. He took up rock-climbing less than two years ago, but he's already an expert. Last year, Dickson scored a second place.
"This year I'm shooting for a double first," he said.
Lisa Greene can be reached at firstname.lastname@example.org or (813) 226-3322.