A study by six researchers, including a University of Colorado at Boulder associate professor and his former doctoral student, shows that amputees who use running-specific prosthetic legs have no performance advantage over counterparts who use their biological legs.
A debate on the matter was spurred when Oscar Pistorius, a bilateral amputee, was barred from the 400-meter dash at the 2008 Olympic Games in Beijing, and other able-body races. The International Association of Athletics Federations that barred Pistorius claimed his Cheetah Flex-Foot prostheses provided significant advantages over non-amputee competitors, agreeing with other studies that found prostheses reduce the energy cost of running. In addition, some have proposed that the lighter weight of specially designed sport prostheses facilitates a quicker swing of the leg.
The new study was published Nov. 4 in Biology Letters, a journal of the Royal Society in London, and is co-authored by Alena Grabowski and Hugh Herr of the Massachusetts Institute of Technology, Craig McGowan of the University of Texas at Austin, William McDermott of The Orthopedic Specialty Hospital in Murray, Utah, and Rodger Kram of CU-Boulder's department of integrative physiology and its Locomotion Laboratory. Grabowski, lead author on the study, received her doctoral degree in integrative physiology at CU-Boulder under Kram in 2007.
After Pistorius was barred from the Olympic Games in January of last year, the U.S. research team presented findings in April 2008 to the Court of Arbitration for Sport in Lausanne, Switzerland, that were key in the reversal of the ban on Pistorius.
"We have already shown that Pistorius runs differently in terms of his biomechanics," said Kram. "Now we have much more clear evidence that his prosthetic legs incur significant disadvantages."