Over the past few years, there has been a great leap in the development of prosthetic limbs. Today, companies create prosthetics that feature "mechatronic" elements, which are normally used in creating robots. These elements turn simple prosthetics into functional substitutes for missing body parts so that some of the latest inventions in technology and science allow users to control prosthetics with the help of their brains.
However, internal prosthetics, like the ones used in the reconstruction of patients' injured faces, still do not include such advanced technologies, which is why they are somewhat awkward and look unrealistic. But that is about to change, as surgeons Craig Senders and Travis Tollefson of the University of California, Davis, look forward to apply artificial polymer muscles to revive the facial features of patients suffering from severe paralysis.
"The face is an area where natural-appearing active prosthetics would be particularly welcome," the surgeons write in a current patent application. The two experts hope that their latest invention in science will provide a solution. They reported that the tests carried out on cadavers proved to be successful, but they haven't had the chance to experience on live patients.
A complete example provided in the patent document explains the way artificial muscles work in helping regain control over eyelids of the patients that suffered spinal injuries or have nervous disorders such as Bell's palsy. There is a number of different disadvantages for people who lost control over their eyelids, including the fact that the eyes can become ulcerated, which can lead to blindness.
Senders and Tollefson describe their invention by saying that a polymer muscle attached to the skull pulls on cords that hook up to the upper and lower eyelids. In case a person attempts to close their eyes, the move generates electrical activity in the muscles that would close the patient's eyelids. The polymer muscle identifies this action and contracts, dragging on its cords to entirely close the eyelids.
According to the surgeons, other methods of using the polymer muscle could be used as well. For example, if a patient has lost control over one eye, as a result of stroke, the system has the ability to control the activity of the normal eye of the person and then synchronize the actions of the damaged eye to match. It is interesting to note that the patent also states that other sensors could be used to close eyes in front of bright light or in case a certain object moves really close to a person's eye. Experts suggest using timing systems to replicate natural blinking patterns.
The two surgeons consider that their latest invention could also be used to revive other facial features, or develop an artificial diaphragm to help a patient breathe, or substitute fingers and hands.