London – Three men who lost the use of their hands have been given bionic replacements activated by brain signals, it emerged yesterday.
A world first, the surgical technique restored function to limbs left almost useless by climbing and car accidents.
And it brings hope to other patients who have suffered traumatic injuries or are born with defects.
The bionic transplants involved men who sustained severe damage to nerves in the neck that control movement and sensation in the arms. Despite conventional surgery, they ended up with no useful hand function and became candidates for the new technique.
First, feeling is restored to the forearm by transplanting some muscle and nerve tissue into the arm – usually from the leg. This boosts the electrical signals from the brain to the arm.
Next, the affected hand is amputated to make way for a robotic prosthesis. Sensors in the new hand respond to the electrical impulses from the brain, allowing the patient to carry out normal activities.
Following comprehensive rehabilitation, the technique restored a high level of hand function, reveals a report in The Lancet medical journal.
Oskar Aszmann, a world expert in reconstructive surgery, performed the operations on three Austrian men over the past three years.
In November, the professor gave a bionic arm to a 21-year-old who had a birth defect.
‘In the future, hand and foot reconstruction will see many new approaches to replace lost limbs and recover function,’ he said. ‘Both biological and technical advances can provide treatments unthinkable only a few years ago.’
Professor Aszmann said the brachial plexus injuries the patients suffered were in effect an inner amputation, separating the hand from the brain.
The injuries often occur as a result of trauma from high-speed collisions, especially in motorcycle accidents, and in contact sports such as rugby and American football. ‘Existing surgical techniques for such injuries are crude and ineffective and result in poor hand function,’ the professor added.
He said the breakthrough was to obtain neural brain signals through nerve and muscle transplants that could be decoded by the bionic hand and translated into actions.
Three months after surgery the men had substantially better functional movement and were able to accomplish everyday tasks such as picking up a ball, pouring water from a jug or using a key.
Professor Simon Kay, who carried out the UK’s first hand transplant, and Daniel Wilks from Leeds Teaching Hospitals, said in a comment in The Lancet that nerve and muscle transfers held promise. But they warned: ‘The final verdict will depend on long-term outcomes, which should include assessment of in what circumstances and for what proportion of their day patients wear and use their prostheses.’
Professor Aszmann, who is based at the Medical University of Vienna, worked with engineers from the University Medical Centre in Göttingen, Germany.
Daily Mail