Biomedical Engineering Theory And Practice/Rehabilitation Engineering

See also Wikipedia,Rehabilitation Engineering.

Overview and History
The term rehabilitation engineering means “the systematic application of engineering sciences to design, develop, adapt, test, evaluate, apply, and distribute technological solutions to problems confronted by individuals with disabilities in functional areas, such as mobility, communications, hearing, vision, and cognition, and in activities associated with employment, independent living, education, and integration into the community.”

Figure 1, taken by René Baumgartner, MD, in Tanzania in 1993, shows a man with an impairment (paralysis of left leg from polio) who uses a simple assistive aid for walking. The aid is similar to one used in Egypt around 1500 B.C.E. as recorded on an ancient Egyptian stele that is now in the Carlsberg Sculpture Museum in Copenhagen. Surprisingly, this similar mobility aid is still in use in many places over the world. Paintings of Brueghel in the Kunsthistorische Museum in Vienna, include many images of persons of the 16th century with disability (for example, limb loss, polio, and cerebral palsy) using crude crutches, sticks, and other simple mobility aids. Ambroise Paré (1510–1590), a French military surgeon of that period, introduced the ligature. From the Napoleonic Wars, today’s rehabilitation teams still prescribe “Nelson’s Knife” to assist persons with only one functional arm to cut and spear meat just as it did for Lord Nelson. America’s Civil War resulted in many limb amputations. In 20th century, with World War I and II, the term, rehabilitation engineering became clear and developed excessively. In 1919, Erzatzglieder und Arbeitshilfen (Replacement Limbs and Work Aids) published in German. It could be considered one of the first major publications in the rehabilitation engineering. In around 1915-1916,Ferdinand Sauerbruch, MD in Berlin worked with an engineer to design an artificial arm. Sauerbruch developed the "team" approach during his work on tunnel cineplasty for direct muscular control of artificial hands and arms. In Russia, Nickolai Bernstein and his associates took a scientific motor control approach to prosthetics. In America, Paul B Magnuson (June 14, 1884–November 5, 1968) as a bone and joint surgeon, continuously investigated new treatments and devices for assisting his patients as they faced unique situations presented by their disability. He founded the Rehabilitation Institute of Chicago (RIC) as well as induced Dr. Stanley Coulter to set up the first Physical Medicine Department in the country. After Dr.Magnuson death, Dr. Compere often related. In order to honor the life and legacy of Paul B Magnuson, M.D, Paul B. Magnuson Award established in 1998.

Major activities in Rehabilitation Engineering
Table Categories of assisted devices from Andrew Szeto((2012)

Assistive Technology
Assistive Technology is defined in the Technology-Related Assistance Act as "any item piece of equipment, or product system, whether acquired commercially off the shelf, modified, or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities". Assistive technology can be created at home and designed specifically for an individual, purchased in a local store, or ordered out of a catalog that is targeted toward people with disabilities and their families. Technology can be high or low. Broadly, Low technology cover daily living aids--from battery operated toys, to eating aids, to mobility aids, to mounting and positioning devices, to recreation, and leisure aids. Some high technology contains computers, software, extended keyboards, electronic communication devices, power wheelchairs, and van lifts for wheelchairs.

Assistive technology cannot resolve all the problems. It can decrease the impact of the disability because the application of technology for persons with disabilities is inexact and will change with time .In addition,similarly disabled persons can have very different needs, wants, and preferences .So,changes in the assistive technology user’s health, living environment, preferences, and circumstances would need periodic reassessment by the user and those rehabilitation professionals. Hopefully assistive technology would increase independence and improve an individual's outlook on life.

However, assistive technology is not without its problems. Many times the devices that are needed could be expensive and resources are not easy to find; or the equipment is purchased and training or support system is not perfect to show the individual how to use it effectively; or the device simply breaks down and needs to be repaired .On the other hand, according to data from the 1990 U.S. Census Bureau’s National Health Interview Survey, about one-third of the assistive devices not needed for survival are unused or abandoned just 3 months after they were initially acquired.

Table Professional Fields in Assistive Technology

Orthotics and Prosthesis in Rehabilitation Engineering
In medicine, a prosthesis, (from Ancient Greekprósthesis, "addition, application, attachment")is an artificial device that replaces a missing body part, which may be lost through trauma, disease, or congenital conditions. Orthotics (Greek: Ορθός, ortho, "to straighten" or "align") is a special field related to the design, manufacture and application of orthoses. An orthosis (plural: orthoses) is "an externally applied device used to modify the structural and functional characteristics of the neuromuscular and skeletal system ". Orthoses and Prosthetics(O&P) are made from various types of materials including thermoplastics, carbon fibre, metals, elastic,fabric or composites with similar properties. Some designs may be purchased at a local retailer. others are more specific and require a prescription from a physician, who will fit the orthosis according to the patient's requirements. An Orthotist and/or Prosthetist is an allied Health Professional who designs, measures, fabricates and fits Orthoses and Prostheses. Orthotists and prosthetists work in special units in major teaching hospitals, rehabilitation centres and the community. They try to magnify the function and comfort of the client by providing the most proper orthotic or prosthetic treatment. O&P combines knowledge of anatomy and physiology, biomechanics, biomaterials and so on.

Upper Extremity Prosthetic Systems
Upper extremity prostheses has a variety of options according to the amputation level: shoulder disarticulation, transhumeral(below elbow) prosthesis, elbow disarticulation, transradial(under elbow) prosthesis, wrist disarticulation, full hand, partial hand, finger, partial finger.
 * Passive Functional / Cosmetic Devices
 * Body Powered / Conventional Devices
 * Myoelectric / External Power Devices
 * Hybrid Devices
 * Adaptive / Recreational Devices

Lower Extremity Prosthetic Systems
Lower extremity prostheses are used at various amputation level. These include hip disarticulation, transfemoral(above knee) prosthesis, knee disarticulation, transtibial prosthesis(below knee), symes, foot, partial foot, and toe.

Principle of Rehabilitation Engineering
This "assistive technology" of the HAAT model is divided into four parts: the human/technology interface, the processor, the activity output, and the environmental interface. The human/technology interface indicates the contact between the person and the technology device. The processor, in this case the switch, is the mechanical or electrical linkage that relays or interprets information from the interface so that the desired task can be accomplished. The activities output are categorized within three basic performance areas: activities of daily living, work and productive activities, and play and leisure activities. The environmental interface is the link between the output of the device and the input from the environment. The final but essential factor in the HAAT model is that the activity enabled by the assistive technology takes place within a social, cultural, and physical context.