STEVE Austin, the bionic man, was hero to a generation of children who grew up in the 1970s. "We can rebuild him. We have the technology" ran the introduction to The Six Million Dollar Man, the cult TV drama starring Lee Majors as a test pilot whose wrecked body was reconstructed at considerable cost, enabling him to run at 60 miles per hour and lift a car with one hand.
Yesterday a Scottish company, Touch Bionics, also declared: "We have the technology," with their announcement that they had successfully developed the world's first commercially available bionic hand. While the i-LIMB Hand may not bequeath its user with the strength of Mr Austin, it has transformed the lives of patients around the world and comes with a more reasonable price tag of £9,000.
The prosthetic device offers greater mobility and authenticity than any previous artificial hand. It allows users to perform far more nimble tasks such as holding a card or turning a key in a lock. The hand has five individually powered digits that can bend like natural fingers and has revolutionised the abilities of patients.
Among the first to use the i-LIMB were members of the American military, where amputations have increased dramatically as a result of the Iraq war. Juan Arredondo, a retired Sergeant with the 2nd Infantry Division, 1/506 Destroyer Company, lost his hand in 2004 after his patrol vehicle was struck by an improvised explosive device.
"Every day that I have the hand, it surprises me. Now I can pick up a Styrofoam cup without crushing it. With my other hand, I would really have to concentrate on how much pressure I was putting on the cup. The i-LIMB hand does things naturally. I can just grab the cup like a regular person."
The development of prosthetic limbs spans centuries, from the peg legs of pirates to the solid wooden hands fitted to veterans of the First World War. In Britain development of artificial limbs picked up pace in the 1960s as the NHS coped with the armless victims of Thalidomide, the drug taken by mothers to suppress morning sickness which resulted in birth defects.
In the 1970s a new form of prosthetic arm was developed using a technology called myoelectric, which connected the muscle signals in a patient's arm to an artificial hand which could then open and close at will. Unfortunately this device was rudimentary, and was often shaped like a claw or pincer. Although it allowed a person to hold an object, there was little subtlety of movement.
By comparison the i-LIMB Hand offers a unique, highly intuitive control system that uses the traditional myoelectric signal input to open and close the hand's lifelike fingers, but has more facilities. Myoelectric controls use the electrical signal generated by muscles in the remaining portion of a patient's limb. This signal is picked up by electrodes that sit on the surface of the skin. As a result users of existing, basic myoelectric prosthetic hands can quickly adapt to the system.
The system does not involve surgery. Two small electrode plates, which detect the minute electrical signals generated by the remaining muscles in the limb stump, are placed against the skin to pick up signals. Traditionally, one electrode is placed on the top of the forearm and one on the bottom.
Patients usually have a sensation that their hand still exists despite it being amputated, something often referred to as phantom feelings. When encouraged to generate a strong signal, patients are often asked to move and flex their missing hand to generate a strong control signal. Before too long, these reflexes become intuitive, and the i-LIMB Hand and patient interact in a symbiotic way.
As each finger can move individually it offers each person a different range of grips such as using the index finger and thumb to pick up small objects, while the addition of a rotating wrist enables the patient to turn keys in a lock, an impossibility under the previous system.
"It is a paradigm shift," said David Gow, the director of rehabilitation engineering services at NHS Lothian, who invented the hand. "It will change the face of prosthetics forever. It is now much more human."
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A big hand for the inventors, please.