This month, Zac Vawter climbed the 103 flights of stairs of the tallest building in North America.
What made his feat particularly remarkable was that, following a motorcycle crash three years ago, Mr Vawter had most of his right leg amputated - and his recent ascent up 2,109 steps in the Willis Tower in Chicago was accomplished using a mind-controlled, bionic leg.
Mr Vawter can operate his prosthetic leg, costing about US$8 million (Dh29.3m) and weighing 4.5kg, using his brainwaves. The process works through a medical technique called "targeted muscle reinnervation". It is a new surgical procedure that reassigns nerves that once controlled the lost limb to a spare muscle set in the remaining part of the limb. By reassigning existing nerves, doctors can make it possible for amputees to control their prosthetic devices by merely thinking about the action they wish to perform. When Mr Vawter thinks about moving his ankle, his hamstring begins to shift and pushes the prosthetic forward.
Once considered only experimental, these types of procedures are now being conducted at hospitals such as Johns Hopkins in the United States for people who have lost a leg, arm or even a hand.
Prosthetic limbs are becoming increasingly high-tech - and customisable. Some of the devices are still in testing phase but work with features on a smartphone to help an amputee make adjustments without having to physically grapple with the prosthetic. Others that are already on the market wirelessly connect data collected from an artificial limb to a clinician.
There are even custom colours patients can choose from, in a similar manner to the way makers of mobile phones and laptops try to differentiate their models.
Ottobock's C-Leg, for one, comes with "limited edition" colours such as glossy black or hot pink.
The worldwide market for prosthetics, which includes the design, manufacturing and fitting of artificial limbs that typically cost $10,000 to $65,000, is projected to reach $15.3 billion this year and grow to $23.5bn by 2017, according to data from Global Industry Analysts. An ageing population and the rising prevalence of health issues such as diabetes, as well as degenerative joint diseases such as arthritis and osteoporosis, is building demand for prosthetics.
More people are also incurring sports injuries, which is driving up sales for devices, particularly in the prosthetic foot and ankle market, which was valued at $3.2bn last year and is expected to hit $4.5bn in five years, according to a research report from MarketsandMarkets.
Certain regional trends are also taking shape. Sales of prosthetics sold in China and India, as well as Latin America, are expected to grow the fastest thanks to steady economic development and increasing awareness about implant procedures.
Meanwhile, countries in the Middle East are also becoming more important for future growth. "The Middle East is looking for the higher-end solutions," says Kim De Roy, the marketing director for Europe, the Middle East and Africa at Össur, a global orthopaedics manufacturer. "We've seen it in our own sales numbers that there is more demand there over the last two or three years."
To some degree, recent changes in prosthetics have followed advancements in the consumer electronics industry. In 1997, Ottobock rolled out the C-Leg, its first prosthetic knee embedded with a microprocessor. It retails at $35,000 to $45,000, which includes fitting, manufacturing and therapy costs. It monitors each step about 50 times a second and helps to prevent users from falling by varying the amount of hydraulic fluid moved around the knee depending on the situation.
Following its initial release, the C-Leg was updated and made able to connect wirelessly through Bluetooth technology to a desktop computer. This made it possible for clinicians to more easily change a prosthetic's mode, depending on whether an amputee had to stand for a long time - if they were a surgeon, for example - or wanted to go Rollerblading.
The company's next generation innovation, known as Genium, came out two years ago and claims to be much more sensitive to the environment and intuitive. Unsurprisingly, it is also more expensive at $70,000 to $80,000.
This prosthetic knee still uses a microprocessor, but it helps amputees step backwards, which many could not do easily before. And it facilitates quicker steps in different directions because the Genium includes "a couple more sensors and more complex algorithms for response", says Karen Lundquist, the communications director for Ottobock in the US.
"They've been saying we need an app for that," adds Ms Lundquist, "and I think they're right."
Other prosthetics makers are already making moves into the app space.
Orthocare Innovations, which is based in the US, plans to release a mechanical limb with a built-in electronic sensor that would hook up to an amputee's iPhone through a mobile app. The technology makes it possible for an individual to adjust the height of their heel as well as relay information about all the steps they have taken to their medical professional, who could work on further improvements. "The era of connected prosthetics is here," says Orthocare Innovations in one of its online advertisements.
Yet experts warn it normally takes about a decade for many new features to trickle down to the majority of the market.
Prohibitively high prices are often one major barrier because medical insurers may be reluctant to offer reimbursements right away. But some countries, including many in the Middle East and North Africa, lack the necessary infrastructure to educate patients and provide them with proper therapy. Still, manufacturers continue rolling out new innovations.
Advancements for prosthetic hands include more sophisticated, customisable software. The so-called "i-limb ultra" hand from Touch Bionics can be programmed to complete a variety of daily tasks, with features such as a precision pinch mode for handling small objects, index pointing for typing on a keyboard or a natural position while walking.
Össur's Power Knee, which the company says is expected to cost $60,000 to $65,000, features a motor to help create momentum and reproduce the power lost after amputation above the knee. "The prosthetic will actually help and lift you up," says Mr De Roy. "The patient has the ability to spread the forces and strain over two legs."
However, some amputees avoid high-tech gadgetry in their prosthetics to survive, professionally.
This summer, Oscar Pistorius won a couple of gold medals for South Africa in the 2012 Paralympic Games in London. The 26-year-old, given the nickname "Blade Runner" for the look of his prosthetic legs, had both limbs amputated below the knees as a child. He became a favourite with fans around the world while finishing eighth against able-bodied athletes during the 4x400 metre relay in the main London Olympics.
He is, understandably, sensitive to arguments his "blades" gave him an unfair advantage.
When asked what he thought about the recent advancements in prosthetics and how they might help athletes with disabilities, his spokeswoman replied: "Oscar cannot race on any advanced running legs and does not aim to make any gains from technology".
But it seems increasingly likely the era of The Bionic Games may not be too far off and the words of the fictional character who created TV's Steve Austin, The Six Million Dollar Man, are starting to sound less fanciful: "We have the capability to make the world's first bionic man. Steve Austin will be that man. Better than he was before.
"Better, stronger, faster."