Gone are the days when the people (imagine pirates) used to have wooden legs and arms, when their limbs were amputated.
Nowadays, science has evolved enough to allow humans to play God, by creating the divine maker’s creation using his own hands. Although we do not do such a perfect job, and we are still very crude in this process, with the advent of newer elements and abilities to join elemental carbon and other molecules in the ways we deem useful, we have been largely successful in making artificial body parts. These parts are non-functional, of course, unless special circuitry is introduced. But they do a very good job of emulating the functions of real limbs and body parts.
The human body is fragile, and losing limbs is a more frequent occurrence than you might imagine. The market of prosthetics stands at $2.8 Billion, globally. This counts for a lot. It shows that there are hundreds of thousands of people who need such parts, and are willing to pay for them. Nobody wants to lead the life of a cripple. Our scientific explorations have made sure that we will not have to. Composite materials are increasingly being used for these purposes. Due to their controllable light weight and extremely strong and stiff nature, composite materials like carbon fiber, and other composite materials (some of which are made of resins) are used for making prosthetics and implants in the medicine industry. Composite material is used in a lot of applications, some of which are listed below:
Carbon fiber is mainly used for making prosthetic feet for patients who have severed feet. Due to its special characteristic of “dynamic response”, it can emulate the human feet: it stores energy when the heel-strike phase of walking takes place, and returns it when the toe-off phase is there. Currently, most foot prosthetics are made on the leaf-spring model. SpringWalk by Ron Nelson of ClosedMold Composites LLC is one such prosthetic foot, which is made of bladder molding and resin transfer molding. Its molding process is semi-automated, as opposed to the mostly manual process of other products, and this could make it competitive.
Implantable polymers like polyetheretherketone (PEEK) have long been used for permanent body implants. Newer composite materials, owing to their neutral nature, are gaining more approvals from the US FDA and the European Commission. According to Julius Wolff’s Law of Bone Adaptation, repeated mechanical stresses on the bones lead to remodeling of the bones, and ultimately strengthening. The composite materials are strong, but also flexible, and thus, they do not take away all the load of the bones, but assist them in bearing loads, like real bones would do. This makes them natural replacements.
While performing surgeries with equipment like bone saws, drills and the like, the bodily fluids need to be protected from the lubricating oils of these devices, and these devices, in turn, need to be protected from bodily fluids. Companies like Bal Seal Engineering (California) have been using spring-energized sealing solutions for such purposes, and these have been working wonderfully for them: even better than the elastomers that the old-school industry players use. Elastomers do not seal well in medical autoclaves, which is an important consideration while selecting a seal material. This is where Bal Seal’s “SP45”, a proprietary blend of composite materials, comes to the rescue. It hits performance targets even at high temperatures.
When internal body parts have been supported with composite materials, X-rays should be able to see through them, in case there are troubles in other body parts. Thankfully, carbon fiber is a radiolucent material, and absorbs very low levels of radiant energy, letting most of it pass through, thus enabling proper imaging of the body using the various imagine techniques. Carbon fibers are also strong and flexible enough to support the body in even a cantilever type system with no immediate supports.
Dental materials that are currently used for filling and the like, are not exactly perfect. Dentists are still looking for better ways to fill the cavities and form better bonds with the tooth enamel. Hybrid Plastics (California) is a company that is developing such a material that is more durable and has better adhesive capabilities. Nanostructured materials are being used for this purpose. Although nanotechnology is still in a very nascent form, it shows great promise, and composite materials can be nanostructured to have desired features and capabilities.
It has long been deemed fruitful to have surgical products that do not need large incisions that lead to (often) long-term pains for patients, and long recovery periods. There has been rapid research in finding and creating technology that would allow the surgeon to use high-technology equipment that would allow use of control equipment outside the body that control micro-sized surgical devices that work in the body cavities and perform the surgery. In this method, an incision large enough to put in a tube (cannula) into the body that contains the probes, monitors, and surgical instruments that are needed to perform the surgery. The rest is controlled from outside the body, thus eliminating the need to do it all by hand. Surgical innovations Group plc (U.K.) has been developing such instruments, such as their scissor-like, eight component forceps, that make such minimally invasive surgeries possible.
As we can see, composites have been revolutionizing the way medical instruments are made and maintained. The very procedures to perform medical operations are being changed, and things are becoming more and more patient friendly. These materials can be engineered to have the strength and flexibility as is needed, and this makes it possible to make numerous applications possible.