Amputees now able to receive functioning hands that can feel
Most everyone has seen a movie portraying a pirate with a hook on the end of his arm that allows for a few basic functions. Medical technology has now surpassed that primitive prosthesis. Recent advances have shown amazing progress. Not only are hand transplants now possible but also manufactured hands are being directly connected to the patient’s nerves.
The latest advancement was reported by Silvestro Micera, PhD of Switzerland’s École Polytechnique Fédérale de Lausanne (EPFL) at the 2013 Annual Meeting of the American Association for the Advancement of Science (AAAS; February 14 through February 18) in Boston. The new bionic hand under development at EPFL contains wiring that connects it directly into the nervous system. Dr. Micera, who is Head of the Translational Neural Engineering Laboratory at EPFL, and colleagues explain that the new bionic hand may one day return dexterity and the sensation of touch to an amputee.
The scientists tested their system by implanting “intraneural electrodes” into the median and ulnar nerves of an amputee. The electrodes stimulated the sensory peripheral system, delivering different types of touch feelings. Then, the researchers analyzed the motor neural signals recorded from the nerves and found that information related to grasping could indeed be extracted. That information was then used to control a hand prosthesis placed near the subject but not physically attached to the arm of the amputee. Dr. Micera explained, “We could be on the cusp of providing new and more effective clinical solutions to amputees in the next years.”
A new clinical trial is expected to soon get underway as part of the Italian Ministry of Health’s NEMESIS project; it will carry this research a step further by connecting the prosthetic hand directly to the patient for the first real-time, bidirectional control using peripheral neural signals. Results are not yet available; however, the researchers hope to find still further improvement in the sensory feedback and overall control of the prosthetics with this new method.
Meanwhile, transplantation of donor hands is being successfully performed. On March 7, 2011, UCLA Medical Center announced that surgeons there had performed the first hand transplant in the western United States. The transplant, which took 14 hours, was performed on a 26-year-old mother from Northern California, Emily Fennell, who lost her right hand in a traffic accident. Ms. Fennell lost her right hand after it was crushed in a roll-over car accident in June 2006. After the amputation, occupational therapists helped her learn to use her left hand for all tasks, including tying her shoes, writing, dressing and even driving a car. She tried a prosthetic hand and traditional ‘hook’ prosthesis but stopped using them because they didn’t provide the functionality she desired.
UCLA notes that the procedure was only the fourth center in the nation to offer this procedure, and the first west of the Rockies; it was the 13th hand transplant surgery performed in the United States. A team of 17 surgeons, anesthesiologists, operating room nurses, and technicians were involved in the effort to graft the hand onto the patient. The operation began with two surgical teams working simultaneously to prepare the donor graft and the recipient. At 4:30 a.m. on Saturday, four-and-a-half hours after the operation began, the donor limb was joined to the recipient. The surgeons then began the complex work of attaching tendons, blood vessels and nerves to complete the surgery. Following the surgery, the patient was brought back to her room, where she was met by family members.
Ms. Fennell can now carry papers in her right hand, grip a steering wheel and paint her fingernails on both hands. “It has been surreal to see that I have a hand again and be able to wiggle my fingers,” the single mother said. She explained, “My six-year-old daughter has never seen me with a hand. She looked at it, touched it and said it was “cool.” She added, “I know it will take time to get there, but my goal is to function like I have two normal hands and not even have to think about it.” On January 1, 2012, Ms. Fennel showed off her new hand as she rode on the Donate Life float in the 123rd Rose Parade is themed “Just Imagine — One More Day.” The float featured floral clocks and clock towers from around the world, reminding all that time is precious.