Biomechanical engineering
Biomechanical engineering is a specialized field that merges mechanical engineering principles with biology and medicine, focusing on the relationship between structures and functions in living organisms. This multidisciplinary area encompasses the study of cell and tissue mechanics, tissue engineering, and physiological systems, with applications ranging from the design of medical implants to the development of surgical procedures. Researchers utilize various methods, including imaging and computational techniques, to investigate how biological systems respond to physical forces, thereby enhancing treatment options and diagnostic capabilities.
The roots of biomechanical engineering trace back centuries, with significant contributions from historical figures like Aristotle and Leonardo da Vinci, but it has only recently emerged as a distinct field. The discipline has evolved alongside advancements in technology, enabling the creation of complex models that guide the design of artificial organs, joints, and other medical devices. Professionals in this field also apply principles of biomechanics to improve product designs in various industries, such as ergonomics and sports equipment.
As awareness of biomechanical engineering grows, so does its potential for innovation in health care and industry, paving the way for future developments in cosmetic surgery and weight-loss devices. With increasing public interest and investment, the field is poised for continuous expansion, highlighting its significance in improving health outcomes and enhancing quality of life.
Biomechanical engineering
Summary
Biomechanical engineering is a branch of science that applies mechanical engineering principles such as physics and mathematics to biology and medicine. It can be described as the connection between structure and function in living things. Researchers in this field investigate the mechanics and mechanobiology of cells and tissues, tissue engineering, and the physiological systems they comprise. The work also examines the pathogenesis and treatment of diseases using cells and cultures, tissue mechanics, imaging, microscale biosensor fabrication, biofluidics, human motion capture, and computational methods. Real-world applications include the design and evaluation of medical implants, instrumentation, devices, products, and procedures. Biomechanical engineering is a multidisciplinary science, often fostering collaborations and interactions with medical research, surgery, radiology, physics, computer modeling, and other areas of engineering.
Definition and Basic Principles
Biomechanical engineering applies mechanical engineering principles to biology and medicine. Elements from biology, physiology, chemistry, physics, anatomy, and mathematics are used to describe the impact of physical forces on living organisms. The forces studied can originate from the outside environment or be generated within a body or single structure. Forces on a body or structure can influence how it grows, develops, or moves. A better understanding of how a biological organism copes with forces and stresses can lead to improved treatment, advanced diagnosis, and prevention of disease. This integration of multidisciplinary philosophies has lead to significant advances in clinical medicine and device design. Improved understanding guides the creation of artificial organs, joints, implants, and tissues. Biomechanical engineering also has a tremendous influence on the retail industry, as the results of laboratory research guide product design toward more comfortable and efficient merchandise.
Background and History
The history of biomechanical engineering, as a distinct and defined field of study, is relatively short. However, applying the principles of physics and engineering to biological systems has been developed over centuries. Many overlaps and parallels to complementary areas of biomedical engineering and biomechanics exist, and the terms are often used interchangeably with biomechanical engineering. The mechanical analysis of living organisms was not internationally accepted and recognized until the definition provided by Austrian mathematician Herbert Hatze in 1974: "Biomechanics is the study of the structure and function of biological systems by means of the methods of mechanics."
Greek philosopher Aristotle introduced the term "mechanics" and discussed the movement of living beings around 322 BCE in the first book about biomechanics, On the Motion of Animals. Leonardo da Vinci proposed that the human body is subject to the law of mechanics in the 1500s. Italian physicist and mathematician Giovanni Alfonso Borelli, a student of Galileo's, is considered the "father of biomechanics" and developed mathematical models to describe anatomy and human movement mechanically. In the 1890s, German zoologist Wilhelm Roux and German surgeon Julius Wolff determined the effects of loading and stress on stem cells in the development of bone architecture and healing. British physiologist Archibald V. Hill and German physiologist Otto Fritz Meyerhof shared the 1922 Nobel Prize for Physiology or Medicine. The prize was divided between them. Hill won "for his discovery relating to the production of heat in the muscle"; Meyerhof won "for his discovery of the fixed relationship between the consumption of oxygen and the metabolism of lactic acid in the muscle."
The first joint replacement was performed on a hip in 1960 and a knee in 1968. The development of imaging, modeling, and computer simulation in the latter half of the twentieth century provided insight into the smallest structures of the body. The relationships between these structures, functions, and the impact of internal and external forces accelerated new research opportunities into diagnostic procedures and effective solutions to disease. In the 1990s, biomechanical engineering programs began to emerge in academic and research institutions around the world, and the field continued to grow in recognition in the twenty-first century.
How It Works
Biomechanical engineering science is extremely diverse. However, the basic principle of studying the relationship between biological structures and forces, as well as the important associated reactions of biological structures to technological and environmental materials, exists throughout all disciplines. The biological structures described include all life forms and may include an entire body or organism or even the microstructures of specific tissues or systems. Characterization and quantification of the response of these structures to forces can provide insight into disease process, resulting in better treatments and diagnoses. Research in this field extends beyond the laboratory and can involve observations of mechanics in nature, such as the aerodynamics of bird flight, hydrodynamics of fish, or strength of plant root systems, and how these findings can be modified and applied to human performance and interaction with external forces.
As in biomechanics, biomechanical engineering has basic principles. Equilibrium, as defined by British physicist Sir Isaac Newton, results when the sum of all forces is zero and no change occurs and energy cannot be created or destroyed, only converted from one form to another.
The seven basic principles of biomechanics can be applied or modified to describe the reaction of forces to any living organism.
- The lower the center of mass, the larger the base of support. The closer the center of mass to the base of support, and the greater the mass, the more stability increases.
- The production of maximum force requires the use of all possible joint movements that contribute to the task's objective.
- The production of maximum velocity requires the use of joints in order—from largest to smallest.
- The greater the applied impulse, the greater increase in velocity.
- Movement usually occurs in the direction opposite that of the applied force.
- Angular motion is produced by the application of force acting at some distance from an axis, that is, by torque.
- Angular momentum is constant when a body or object is free in the air.
The forces studied can be combinations of internal, external, static, or dynamic, and all are important in the analysis of complex biochemical and biophysical processes. Even the mechanics of a single cell, including growth, cell division, active motion, and contractile mechanisms, can provide insight into mechanisms of stress, damage of structures, and disease processes at the microscopic level. Imaging and computer simulation allow precise measurements and observations to be made of the forces impacting the smallest cells.
Applications and Products
Biomechanical engineering advances in modeling and simulation have tremendous potential research and application uses across many healthcare disciplines. Modeling has resulted in the development of designs for implantable devices to assist with organs or areas of the body that are malfunctioning. The biomechanical relationships between organs and supporting structures allow for improved device design and can assist with the planning of surgical and treatment interventions. The materials used for medical and surgical procedures in humans and animals are being evaluated and some redesigned, as biomechanical science is showing that different materials, procedures, and techniques may be better for reducing complications and improving long-term patient health. Evaluating the physical relationship between the cells and structures of the body and foreign implements and interventions can quantify the stresses and forces on the system, which provides a more accurate prediction of patient outcomes.
Biomechanical engineering professionals apply their knowledge to develop implantable medical devices that can diagnose, treat, or monitor disease and health conditions and improve the daily living of patients. Devices used in the human body are highly regulated by the Food and Drug Administration (FDA) and other agencies. Pacemakers and defibrillators, also called cardiac resynchronization therapy (CRT) devices, can constantly evaluate a patient's heart and respond to changes in heart rate with electrical stimulation. These devices greatly improve therapeutic outcomes in patients afflicted with congestive heart failure. Patients with arrhythmias experience greater advantages with implantable devices than with pharmaceutical options. Scientists have designed cochlear implants for patients who are deaf or hard of hearing, which attach to a patient's auditory nerve to detect sound waves and process them to be interpreted by the brain as sound. Patients who have had cataract surgery used to have to wear thick corrective lenses to restore any standard of vision, but with the development of intraocular lenses that can be implanted into the eye, their vision can be restored, often to a better degree than before the cataract developed.
Artificial replacement joints comprise a large portion of medical implant technology. Patients receive joint replacement when their existing joints no longer function properly or cause significant pain because of arthritis or degeneration. Hundreds of thousands of hip replacements are performed in the United States each year, and this number grew significantly as the baby boomer population aged. Artificial joints are normally fastened to the existing bone by cement, but advances in biomechanical engineering have led to a new process called "bone ingrowth," in which the natural bone grows into the porous surface of the replacement joint. Biomechanical engineering contributes considerable knowledge to the design of artificial joints, the materials from which they are made, the surgical procedure used, fixation techniques, failure mechanisms, and prediction of the lifetime of the replacement joints.
The development of computer-aided (CAD) design has allowed biomechanical engineers to create complex models of organs and systems that can provide advanced analysis and instant feedback. This information provides insight into developing designs for artificial organs that align with or improve the mechanical properties of biological organs.
Biomechanical engineering can provide predictive values to medical professionals, helping them develop a profile that better forecasts patient outcomes and complications. An example of this is using finite element analysis to evaluate aortic-wall stress, which can remove some of the unpredictability of expansion and rupture of an abdominal aortic aneurysm. Biomechanical computational methodology and imaging and processing technology advances have provided increased predictability for life-threatening events.
Nonmedical applications of biomechanical engineering also exist in any facet of industry that impacts human life. Corporations employ individuals or teams to use engineering principles to translate scientifically proven principles into commercially viable products or new technological platforms. Biomechanical engineers also design and build experimental testing devices to evaluate a product's performance and safety before it reaches the marketplace, or they suggest more economically efficient design options. Biomechanical engineers also use ergonomic principles to develop new ideas and create new products, such as car seats, backpacks, or specialized equipment and clothing for elite athletes, military personnel, or astronauts.
Careers and Course Work
There are various career choices in biomechanical engineering, and study in this field often evolves into specialized work in related areas. Students who earn a bachelor's degree from an accredited biomechanical engineering program may begin working in areas such as medical devices, implants, or product design. Most teaching positions require a master's or doctoral degree. Some students continue to medical school.
Biomechanical engineering programs are composed of a cross-section of coursework from many disciplines. Students should have a strong aptitude for mathematics as well as biological sciences. Elements from engineering, physics, chemistry, anatomy, biology, and computer science provide core knowledge applied to mathematical modeling and computer simulation. Experimental work involving biological, mechanical, and clinical studies is performed to illustrate theoretical models and solve important research problems. The principles of biomechanical engineering can have vast applications, ranging from building artificial organs and tissues to designing products that are more comfortable for consumers.
Biomechanical engineering programs are often considered a subdiscipline of engineering or biomedicine. However, some schools, such as Stanford University, have created interdisciplinary programs that offer undergraduate and graduate degrees in biomechanical engineering.
Social Context and Future Prospects
The diversity of studying the relationship between living structure and function has opened up vast opportunities in science, health care, and industry. In addition to conventional implant and replacement devices, the demand is growing for implantable tissues for cosmetic surgery, such as breast and tissue implants, as well as implantable devices to aid in weight loss, such as gastric banding.
Reports of biomechanical engineering triumphs and discoveries often appear in the mainstream media, making the general public more aware of the scientific work being done and how it impacts daily life. Sports fans learn about the equipment, training, and rehabilitation techniques designed by biomechanical engineers that allow their favorite athletes to break performance records and return to work sooner after being injured or having surgery. The public is accessing more information about their own health options than ever before, and they are becoming knowledgeable about the range of treatments available to them and the pros and cons of each.
Biomechanical engineering and biotechnology is an area that is experiencing accelerated growth, and billions of dollars are being funneled into research and development annually. This growth is expected to continue.
Bibliography
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