Figure skating is an unusual sport on many levels, not the least of which is the lack of change in the equipment. By all counts, the figure skate has improved little since the 1950s, while the sport has gotten more physically demanding and acrobatic. The result has been an increase in the number of serious and debilitating joint injuries.

But researchers from the University of Delaware in Newark are working to redefine the traditional figure skate by adding a hinge to the boot.

"Every other sport you can think of has added or improved protective gear for their athletes in recent years," said Jim Richards, Distinguished Professor of Health, Nutrition, and Exercise Sciences and head of the university's biomechanics laboratory. "The exception is skating, where the kids are starting younger and doing more and more jumps, and they clearly need better protection from injury. You have skaters in their 20s who need knee and hip replacement surgery, and that shouldn't be happening."

The problem, according to Richards, is that the traditional figure skate isn't well suited to the jumping that competitive skaters do. With a traditional skate, the skater lands a jump flat-footed. This causes tremendous impact up the leg and into the spine, according to Rich-ards. "If your toe hits the ground at the same time, or very close to the same time, as your heel, the total force of the impact spikes as much as eight to 10 times your body weight, and for a very short period of time," Richards said.

The hinged boot design Richards is working on allows the skater to flex the ankle and point the toe seven degrees for landing. This increases the landing time and allows the ankle to absorb more of the impact of the jump.

The lower part of the hinged figure skate looks a lot like a shoe. An ankle cuff attaches to the lower part of the skate with what looks like a bolt or t-nut, according to Richards. This t-nut is the hinge that allows skaters to move their feet up and down as if operating a gas pedal.

The design allows skaters to point their toes during a jump, so they can come down toe-first, with the rest of the foot hitting the ice more slowly.

A new figure skate design adds a hinge at the ankle, to help minimize jump-related injuries.

Earlier this year, figure skate manufacturer Jackson Ultima of Waterloo, Ontario, entered into a partnership with the University of Delaware and contracted with Richards to develop a prototype of the hinged, or articulated boot. The University of Delaware now holds a preliminary patent on the tongue design for the boot, which has a flexible rubber insert, a buckle to hold the upper part of the boot in place, and laces only below the hinge.

The current iteration of the boot is made of leather, with a composite material sole. The hinge is carbon fiber. By the time the boot comes to market, which is expected by the end of this year, it will be made of a soft and flexible synthetic leather, Clarino, which breathes like natural leather. This material is already widely used in the manufacture of hockey skates.

Richards began developing the hinged boot more than a decade ago, but the company he was working with at the time was sold and went out of the skating equipment business. The concept was revived recently when Jackson Ultima approached him. The company is finishing up the last prototype of the articulated skate before going to market.

While elite competitive figure skaters like U.S. quadruple jumping phenom Timothy Goebel, who has suffered from hip injuries, would benefit greatly from the skate, nine- and 10-year-old children are doing most of the testing, Richards said. "Older skaters want to use what they've always used," he said. "They want to feel the stiffness in the boot; they've built all their jumps around that stiffness, and don't want to relearn those jumps."

Still, Richards said skaters can adjust to the ankle flexibility that the hinged skate provides in just a couple of weeks, and then be able to skate much as they always have. In fact, Richards said that there is some indication that the hinged skate may improve the skater's ability to perform certain jumps, though that was never a design goal.

"We never had in mind an increase in performance," Richards said. "We wanted an increase in safety, with no change in performance. If performance happens to improve, that's a bonus."

The U.S. Figure Skating Association has approved the skate for competition, but in a sport that is as devoted to aesthetics as it is to athleticism, the appearance may make elite skaters reluctant to adopt the new design. "Our hope is that we can get the kids while they're young, and help them avoid the stress fractures that happen to close to 20 percent of skaters at the junior competitive level," Richards said. "The jumps aren't going to go away, so we have to do something to make them less harmful."

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