Adaptive technology is any object or system that is specifically designed for the purpose of increasing or maintaining the capabilities of people with disabilities. Prosthetic limbs are a fine example of such an adaptive technology. While rare, limb amputations have become increasingly common worldwide. Often times, this kind of amputation leaves the victim with the inability to perform necessary daily tasks due to reduced functionality. In an effort to recover the lost functionality, a prosthetic limb can be fitted to the person. Until recently, the benefits from such prosthetics were often outweighed by the burden of their use or attachment to the body. However, new prosthetic limbs have been developed which dramatically increased functionality and in some cases actually overtake the utility of biological limbs. These prosthetics have allowed users to live a productive and normal lifestyle free from limitations. In fact, specialized prosthetics have even been made to allow patients to participate in sports and recreation.
The “Cheetah Leg” is optimized for sprinting. The prosthetic is built from carbon fiber and can boast a high strength at about half the weight of a biological leg. The decreased weight requires less torque to swing forward. This allows for faster rotation with less exertion. The shape of the leg acts as a spring, which stores energy on the heel strike and releases it at the toe-off. The length of the prosthetic also increases the stride of the runner in relation to their height. Overall, the performance of the limb is remarkable for a prosthetic and may even surpass that of a normal leg. In fact, the Cheetah Leg has become a topic of debate in the Olympics due to its possible advantage.
For marine situations, a promising prototype is the “Neptune” flipper. The Neptune is configurable for above and below the knee amputations. The purpose of the Neptune is for balancing the power of the leg kicks of uni-lateral amputations. Also, for bi-lateral amputations, two Neptune flippers could be used to add power to the swim stroke. Since the majority of amputations are due to health conditions, the flipper could allow users to exercise after their surgery. The initiation of a health routine could prevent further limb amputations, and improve the health of the patient.
Prosthetics have also been developed for winter sports. Although a walking-limb can be modified and used, a ski-specific alignment should be performed for the duration of the activity. Additional foot dorsiflexion and external knee support should be added. For advanced users specialty feet, which eliminate the boot, are available. The plantar surface of the ski foot can be modeled after the boot sole and attached directly to the ski bindings eliminating the boot altogether. This eliminates excess weight, but, more importantly, enhances energy transfer to the sporting equipment for more efficient performance. Individuals with uni-lateral amputations will usually opt to use a single ski with modified bi-lateral forearm outriggers. Recently, a prosthetic has been designed specifically for sports that require a loaded, flexed knee position, such as snowboarding. Snowboarders are in bi-lateral dynamic hip, knee and ankle flexion as they negotiate the hill. This new knee is adjustable and produces the weighted knee flexion needed to snowboard successfully. No additional adaptive gear is necessary when using the energy-storing knee.
Recent research efforts have propelled protheses design from century-old devices that were uncomfortable to wear to technically advanced devices. The functionality of the new devices is approaching that of the original limb and, in some instances, surpassing it. These prosthetics have given patients the opportunity to perform daily functions and live a normal lifestyle not limited by the functionality of their prosthetic. Prosthetic limbs are a model example of an adaptive technology.