The bombings at the Boston Marathon cost 14 people at least one limb. But for many, it will not mean a total loss of mobility.
Those maimed in Monday’s attack face long and arduous recoveries but will likely return to active lives, thanks to rapidly advancing prosthetic technologies, some of which are being developed in and around Massachusetts, specialists said Wednesday.
A Bedford company, iWalk, is revolutionizing lower-leg prosthetics with a battery-powered bionic ankle that propels its wearer forward, simulating a natural gait more closely than other artificial joints.
“The technology we have today is good,” said iWalk founder Hugh Herr, who lost both of his legs below the knees in a hiking accident 30 years ago. “In a decade, it will be extraordinary, and in 20 years, it will be unimaginable. If these victims are young enough to see that, they will eventually be able to fully ambulate.”
iWalk’s bionic ankle is available in Newton, a city that marathoners ran through on Monday, at Next Step Bionics & Prosthetics. The care center added the word bionics to its name in January to reflect the high-tech devices now on the market.
“The thing that blew my mind when I saw it is that you can adjust the power with your smartphone,” said Next Step president Matthew J. Albuquerque, who also has offices in Manchester, N.H., and Warwick, R.I. “Fifteen years ago, we were making wooden legs. Now, we’re making bionic legs.”
Next Step also is working on a robotic hand and arm for upper extremity amputees with DEKA Research and Development, the Manchester company founded by Dean Kamen, inventor of the Segway Personal Transporter. Funded by an $18 million government grant, the so-called Luke Arm (named for “Star Wars” character Luke Skywalker) has been featured on “60 Minutes” and holds the promise of unprecedented fine motor function.
With innovations like these, the prosthetics industry is growing quickly, said Dr. Ross Zafonte, vice president of medical affairs for the Spaulding Rehabilitation Network. Improvements have been driven by record numbers of military veterans returning from combat with blast injuries — much like those suffered by Marathon bombing victims, he said.
“In the near future, maybe half a decade, I think we’ll have sensors that allow you to feel a prosthetic foot,’’ Zafonte said. “Right now you have to look and see where the foot is, but it’s always good to feel feedback in your body.”
Already, advanced prostheses come with microprocessors embedded in knees and ankles. The chips collect data about the position of a leg — much like the computer in a luxury SUV scans terrain — 50 times per second.
“There are a lot of components involved in the human gait, though it doesn’t look that difficult,” said Dr. Simona M. Manasian, a physician in Boston Medical Center’s rehabilitation department. “The technology allows the [prosthetic] leg to adjust the way your body would.”
But technology matters little if a prosthesis does not fit perfectly, said Paul Martino, president of United Prosthetics in Dorchester and Braintree. For Marathon bombing victims who need prosthetic limbs, fitting will be a difficult and ongoing process.
The first step after healing from surgery, Martino said, will be to cast a patient’s residual limb and use the mold to fashion a custom socket. Today’s best prostheses achieve what Martino called an “intimate fit” through suction. Pushing the stump into a slightly smaller socket creates a tight seal that breaks only when the push of a button introduces air into the cavity.
But the wounded limb of a Marathon bombing survivor will change in size and won’t be ready for suction for six to 12 months, Martino said. Until that time, it will attach to a prosthesis with an elastic sleeve or a pin at the tip of a well-cushioned sock that locks into the artificial limb, he said.
Herr, who was traveling in Spain on his prosthetic legs, said, “I don’t want to minimize the trauma and pain these people are going through. But I do want to underscore the bright outlook.”