Extract
The use of biotechnology to enhance the overall functional health of individuals is not a new concept. Historically, orthopaedic surgeons have used therapeutic treatments to facilitate healing and improve or enhance the functional status of their patients. In recent years, the term enhancement biotechnology has been used in different contexts, resulting in divergent ethical opinions1. Some suggest that enhancement biotechnology is nothing more than a utilization of one or more means of biotechnology in a health-related manner in order to correct a pathologic condition. This approach involves the use of biotechnology to treat individuals with known diseases, disabilities, or impairments in an attempt to restore them to a normal state of health and fitness. This definition is compatible with the concept of biotechnology being used for therapy. Others suggest that enhancement biotechnology means the utilization of biotechnology to change some physical (e.g., height or size), intellectual, or behavioral characteristic that may be within the range of normal but for which some improvement is desired2. Enhancement is then defined as the use of biotechnology in a nonhealth-related manner in order "to alter, by direct intervention, not disease processes but the ‘normal’ workings of the human body and psyche, to augment or improve their native capacities and performances."1,2
The use of biotechnology to enhance the overall functional health of individuals is not a new concept. Historically, orthopaedic surgeons have used therapeutic treatments to facilitate healing and improve or enhance the functional status of their patients. In recent years, the term enhancement biotechnology has been used in different contexts, resulting in divergent ethical opinions1. Some suggest that enhancement biotechnology is nothing more than a utilization of one or more means of biotechnology in a health-related manner in order to correct a pathologic condition. This approach involves the use of biotechnology to treat individuals with known diseases, disabilities, or impairments in an attempt to restore them to a normal state of health and fitness. This definition is compatible with the concept of biotechnology being used for therapy. Others suggest that enhancement biotechnology means the utilization of biotechnology to change some physical (e.g., height or size), intellectual, or behavioral characteristic that may be within the range of normal but for which some improvement is desired2. Enhancement is then defined as the use of biotechnology in a nonhealth-related manner in order "to alter, by direct intervention, not disease processes but the ‘normal’ workings of the human body and psyche, to augment or improve their native capacities and performances."1,2
In the context of the latter definition, the enhancement of athletic performance through biotechnology has resulted in a current controversy that is confronting orthopaedic surgeons who are involved in sports medicine. The controversial performance-enhancement method is called techno doping, meaning that biotechnology is being used to increase the physical attributes of the human being3,4. One recent example of techno doping is in conjunction with the development of a new type of swimwear specifically designed for use by elite competitive swimmers5. The swimsuit is made of lightweight compressive material with strategically placed panels and a built-in corset to decrease drag and fatigue, resulting in improved speeds and better oxygen efficiency6.
Techno doping also has been mentioned in the controversy surrounding the use of running prostheses by Paralympic track and field standout Oscar Pistorius, whose inspiring story has been widely publicized7-9. This South African was born with congenital absence of the fibula necessitating bilateral below-the-knee amputations at an early age. Utilizing J-shaped, carbon fiber, high-performance prostheses (Cheetah Flex-Foot; Össur, Reykjavik, Iceland), Pistorius has enjoyed near-phenomenal success in competitive running, including his goal to reach the 2008 Beijing Summer Olympics. He competed in three different Olympic qualifying events but fell short of the required performance time by a margin of 0.70 seconds10. Still, his accomplishments are laudable and illustrative of great personal achievement in the face of physical limitations that would normally be associated with considerable disability. His success has stimulated ethical discussions relative to the use of his prostheses.
The primary ethical concern in the case of Oscar Pistorius is whether his prostheses give him an unfair competitive advantage over other runners. It has been implied that his prostheses do not simply correct his limb deficiencies but that they enhance his abilities beyond normal functioning. Accordingly, use of this biotechnological enhancement is characterized by some as cheating because the prostheses give him a competitive edge over able-bodied runners.
Scientific Aspects of Competitive Advantage
Competitive sports activities traditionally are based on a set of rules that are necessary for orderly engagement in the activity as well as the fair assessment of competency and relative skill levels (winners versus losers). Some rules are determined arbitrarily, whereas other rules may be defined on the basis of scientific research. The rules of track and field competition were established by the International Association of Athletics Federations (IAAF) at a time when virtually all of the runners were either able-bodied or competed in the Paralympics. There were no previously defined IAAF rules that could be specifically applied to the case of Pistorius. His successes resulted in the need for clarification in regulations related to the use of prostheses. The IAAF rules were amended in 2007 to ban the use of "any technical device that incorporates springs, wheels or any other element that provides the user with an advantage over another athlete not using such a device."11 However, this rule was not based on objective or definitive research data as, at that time, there had been no study performed to prove Pistorius had an actual competitive advantage over other runners.
Only general hypotheses regarding Cheetah Flex-Foot prostheses could be made due to the lack of definitive scientific data. Specifically, it has been suggested that these prostheses have foot blades that are longer than necessary, which allow the runner to cover more ground with each stride. There was some concern that the prosthetic limbs would make runners taller than they would be on natural legs and thus would unfairly lengthen the stride, resulting in improved running times. The IAAF commissioned biomechanics expert Gert-Peter Brüggemann to evaluate these concerns. Brüggemann suggested that Pistorius expends 25% less energy than able-bodied athletes when running at the same speed, and that use of his prosthetic limbs also results in less vertical motion combined with 30% less mechanical work when lifting the body. It was his opinion that Pistorius had considerable advantages over athletes without prosthetic limbs12. In order to further examine some of Brüggemann's conclusions, Pistorius himself participated in a performance study conducted at Rice University13,14. The research performed by Peter Weyand and a group of biomechanics and physiology experts from six institutions disagreed with Brüggemann's position that Pistorius' prostheses give him metabolic or mechanical advantage over other runners. One of the researchers, Rodger Kram, disputed the concern that Pistorius had 25% less energy expenditure than able-bodied runners because "anaerobic energy supply cannot be quantified."13,14 The researchers reported that "Pistorius' rates of metabolic energy expenditure do not differ from elite non-amputee runners. In particular, he has nearly the same running economy, or rate of oxygen consumption at submaximal speeds, and a similar maximal rate of oxygen consumption as elite non-amputee runners." They further postulated that Pistorius fatigues in the same manner that other able-bodied athletes do because his ability to maintain speed while performing longer sprints (his speed-duration relationship) is essentially identical to that of able-bodied runners. The Rice study contributed to the May 2008 Court of Arbitration for Sport (CAS), which ruled that conclusive evidence was not available to prove that use of the Cheetah prostheses gives Oscar Pistorius an unfair advantage over able-bodied athletes and which declared that Pistorius was eligible to compete. Despite this regulatory decision, there is still lack of agreement regarding the scientific aspects of competitive advantage in this case, which reinforces the need for further research specific to this subject.
Philosophical Aspects of Competitive Advantage
Clarifying the purely scientific aspects of competitive advantage may be easier than resolving the philosophical differences that exist. For instance, some posit that there are naturally occurring or genetic differences among individuals, to the extent that racial, sex, and anthropomorphic inequalities are inevitable, regardless of what rules are made15. They further reason that performance enhancers should be acceptable in order to level the playing field for the naturally disadvantaged athlete15. Therefore, the use of prostheses by a bilateral amputee would not be considered a competitive advantage, especially if the amputee was performing against able-bodied runners. Not all stakeholders in this debate hold that opinion. The Charter for Ethics in Sport establishes equal treatment for all as the first of its seven principles16. This charter condemns discrimination based on nationality, religious and political affiliations, age, sex, sexual orientation, and social background. However, the charter makes no specific mention regarding discrimination based on physical disabilities or health status. It can be argued that regulatory decisions should not be altered to allow Oscar Pistorius' participation in able-bodied competition because he is already being given an equal opportunity to compete. Paralympic competition is among individuals who are disabled, but it is the reason that different competitive levels were designed. Furthermore, there is nothing to suggest that Pistorius' individual best performance would go unrecognized even if he is competing against disabled athletes.
A final argument that proponents of enhancement biotechnology offer is that their critics arbitrarily believe that certain enhancements are acceptable or fair, but others are not17. This point of disagreement could be included in the discussions regarding prosthetic enhancements. Some individuals make a distinction between enhancements of equipment versus enhancements done directly to the body18. Supporters of this position would agree that modifications to a tennis racquet or material improvements in the fabrication of a baseball are acceptable, but any enhancement directly affecting the body, such as a prosthesis, should not be allowed.
Economic Aspects of Competitive Advantage
Questions also arise regarding fairness and equality considerations from an economic standpoint. For example, do disabled individuals from affluent national or familial backgrounds have better access to the relatively expensive prostheses that may be cost prohibitive for economically and physically disadvantaged athletes? If so, then this could give financially advantaged athletes an unfair competitive advantage over others.
Personal autonomy is a primary component of the ethical framework in most contemporary cultures. However, restrictions on autonomy can be considered acceptable if the designated limitations are intended to prevent harm to others or the individual19.
The first practical application of the harm principle involves assessing the personal and public safety of any potential enhancement biotechnology. There has been limited discussion regarding potential individual or societal harm from the use of Pistorius' prostheses. There has been conjecture that he could conceivably fall and injure himself. However, neither this nor any other specific personal harm issue has been realized7. Even if there are potential adverse side effects from running in these prostheses, virtually all sports, including Paralympic competition, pose an inherent amount of risk that the competing athlete has to be willing to accept20,21. The hypothesis that Pistorius could fall and hurt himself has been expanded to suggest that he could fall and potentially obstruct the lanes of other runners and thus cause them harm. This has not been confirmed as a major or recurrent reality.
Critics of enhancement biotechnology point out that harm to other athletes can also come about if the athletes feel pressured or coerced into using harmful biotechnology that has been used in a successful way by other competitors17. This pressure may be the indirect pressure of the individual's competitive spirit or the direct pressure of parents, coaches, trainers, or fans. Some proponents of enhancement biotechnology suggest that intense competition and high personal risks are part of the nature of athletics. They further suggest, in a reductionistic fashion, that if (for whatever reason) the athlete is not willing to utilize enhancement biotechnologies, then perhaps they should not participate in the sport17. It is not likely that able-bodied individuals will resort to amputations and prostheses in order to be competitive in sports. However, the exact limits of what an individual athlete is willing to do in order to be competitive have not yet been defined. This quest for athletes to gain physical competitive advantage is evidenced in the recent requests from baseball players to surgeons for elbow reconstructions of apparently intact elbows22.
Societal harm may occur if enhancement biotechnologies magnify some of the already intense and competitive business practices employed by manufacturers of sports equipment. For example, there is current litigation in the swimwear industry involving the marketing practices used by a company in promoting their newest swimsuit biotechnology. A manufacturer is alleging that one of their competitors is unfairly inhibiting competition by making false and derogatory statements about their product23. Those who do not see this as potential societal harm would argue that litigation is a reality of the business world regardless of whether enhancement biotechnology is involved or not. It may or may not be considered harmful, depending on one's definition of the spirit of sport and competition.
Traditionally, the spirit of sport has emphasized the more virtuous aspects of competition, such as fair competition and safety. The World Anti-Doping Agency describes the spirit of sport with use of words and phrases such as ethics, fair play, honesty, excellence in performance, character and education, fun and joy, teamwork, dedication and commitment, respect for rules and laws, respect for self and other participants, courage, and community and solidarity24. Two Swiss sports associations define their principles in the Charter for Ethics in Sport, which focuses on social responsibility with cultural relevance16. Most of these traditionalists' positions endorse the tenet that participation in sporting competition is valuable whether an individual wins or loses, because there are potential benefits that may prove to be of more personal importance for an individual. Many traditionalists agree that the accomplishments of Oscar Pistorius exemplify a number of these aspects of the spirit of sport. However, other traditionalists also believe that competition should be between similar individuals and not biotechnologies25. They believe it is acceptable to have competition between anthropomorphically similar individuals, even though there are naturally occurring physical and motivational differences. Moreover, they do not believe that competition between technologically enhanced or robotic individuals is acceptable. They warn that this could change the fundamental nature of various sports and also contribute to the dehumanization of the athlete26,27.
Other philosophers have argued that there is no single spirit of sport28 due to the pluralistic nature of society. Opinions on how one should view competition and other topics regarding the spirit of sport, especially among elite athletes, are divided. Proponents of enhancement biotechnology claim that it is acceptable for athletes to choose enhancement measures due to the fact that they are pushing themselves to greater limits than ever before and may need drugs or other technologies to accelerate recovery17,29. Complementary viewpoints further deem these technologies to be acceptable because they are expressions of human ingenuity, ability, and will. Enhancement advocates also adopt the belief that enhancement biotechnology can be justified as a way of compensating for any naturally occurring physical or motivational differences. Savulesco claims that "performance enhancement per se is not against the spirit of sport; it is the spirit of sport."29 He further states that "To choose to be better is to be human." That is, supporters of enhancement biotechnology do not see this as being dehumanizing to the athlete. This position is associated with one aspect of utilitarianism, since it seems to endorse expanding the limits of the acceptable means used to accomplish the desired end of winning.
It is not immediately clear what, if any, consensus will be reached among the differing spirit-of-sport opinions regarding the participation of Oscar Pistorius in Olympic-level competition. It may be that the inevitability of such controversies could result in yet another level of competition beyond the Olympics and Paralympics, where the winners of each of the respective games compete against one another in a totally different venue. This hypothetically different but no less important competition conceivably could increase public awareness regarding the achievements of disabled athletes and give greater validation to some of their exceptional accomplishments.
There are newer biotechnologies that warrant discussion, not only due to their therapeutic benefit, but also because they have the potential to be used for the enhancement of athletic as well as nonathletic human performance. These include genetics, cybernetics, and nanotechnology.
Gene Therapy
Gene therapy involves the treatment of human diseases by the transfer of genetic material to specific cells in order to correct impaired cellular function, introduce a new function, and/or disrupt an existing function30,31. Procedurally, this requires the following steps: identification of the appropriate therapeutic gene(s) needed for transfer; identification of the appropriate location for therapeutic gene insertion; determination as to how the transgene should be transferred to the target cell; determination as to how to regulate the level and duration of transgene expression; and implementation of safety measures32. Evans and Ghivizzani have categorized the orthopaedic applications of gene therapy as being Mendelian or non-Mendelian32,33. The Mendelian diseases include disorders such as osteogenesis imperfecta and lysosomal storage disease. There are three non-Mendelian categories that include chronic diseases (e.g., arthritis and osteoporosis), cancer (e.g., Ewing sarcoma and osteosarcoma), and tissue repair (e.g., bone healing and cartilage repair)33.
The use of such biotechnology for the purposes of preventing or correcting various diseases is not without potential concerns and complications34. Scientifically, there still remain potential patient harm and safety issues35. For example, viral vectors used in gene therapy have been implicated in undesired immune responses, unexpected cancer, and disease transmission. There are also differing philosophical opinions on the acceptability of the two different types of genetic engineering. Some individuals believe that somatic genetic engineering is acceptable, whereas germ-line engineering (sperm, egg, or their immediate precursors) is not36. They believe that the latter type is objectionable due to the fact that germ-line genetic modifications not only affect the individual who has been genetically engineered but can potentially affect the offspring from the engineered individual as well. Because the offspring are not yet born, they cannot choose for themselves whether to have the therapy the parent has chosen. Adherents to this position also posit that any ill effects of the therapy may only be remediated by mandatory sterilization of all affected individuals, which is another ethical issue in and of itself. Contentious economic issues have arisen as a result of gene therapy36. These issues center on the patenting of patient genes and cell lines and any related litigation.
The ethical implications regarding the therapeutic use of gene therapy are not particularly controversial. However, when genetic engineering is offered as a means to enhance normal individuals who have no underlying pathologic condition, greater concerns arise37. For example, there is ongoing research suggesting that genetic manipulation can increase growth factors, fast twitch muscle fibers, and red blood-cell count in athletes17. Wadler describes the nontherapeutic use of genes, genetic elements, and/or cells for potential enhancement of athletic performance as "gene doping."38 Recent advances in genetic mapping may also make it possible to identify potentially elite athletes by their genetic profiles39. There has even been some discussion that reproductive technologies could be used in order to engineer future elite athletes or elite individuals of any other specific profession. Similar to the opposition to techno doping, many oppose the use of gene therapy in competitive athletics because of the potential for an unfair competitive advantage, personal or societal harm, and/or the violation of the spirit of sport. The issue has also been raised as to whether a society that encourages the widespread use of genetic enhancement would be less accepting of people who have not been enhanced40.
Nanotechnology and Cybertechnology
Perhaps less well known but no less important than gene therapy are the fields of nanotechnology and cybertechnology (cybernetics)41. Nanotechnology is the engineering or manipulation of matter with tolerances of a micrometer or less (one billionth of a meter)42,43. A major area of nanoengineering research in orthopaedics involves improving the surface properties of implants to create an environment that is more favorable for bone ingrowth but less favorable for bacterial adhesion and proliferation44. This biotechnology is anticipated to assist in the development of biomaterials to reduce friction and wear, resulting in increased longevity. Other applications include nanotherapeutic drug-delivery tools for the treatment of arthritis, infections, and various cancers44,45.
Another form of biotechnology that is sometimes used in combination with nanotechnology is cybertechnology, which involves the blending of humans with machines, prostheses, or computers41,46. Based on this simplistic definition, orthopaedic patients with prostheses or joint implants can be classified as cybernetic organisms (cyborgs). However, the type of cybernetic modifications under research involve replacement of pathologically impaired body parts with mechanical devices that may even be neurologically controlled through computerized connections made directly to the peripheral or central nervous system. These innovations are far more advanced than what currently exist and will hopefully have a profoundly improved effect on the ambulatory and functional ability of orthopaedically impaired individuals47,48. The recognition by the United States government of the research priority of and importance of converging biotechnologies is evidenced within the National Science Foundation by the establishment of the Nanotechnology, Biotechnology, Information Technology, and Cognitive Science (NBIC) convergence program. This program49 has been developed in order to employ "converging technologies integrated from the nanoscale to achieve tremendous improvements in human abilities, and enhance social achievement."50,51
Most of the published ethical concerns regarding the use of nanotechnology have centered on safety issues51. The primary safety issue is that degradation of nanomaterials produces nanoparticles, which have potential cytotoxic side effects52. This requires an understanding of the particle clearance rates and their cytocompatibility with involved organ systems. In terms of potential societal harm, there has been discussion regarding the potential but unknown environmental hazards of newer nanomanufacturing processes53. Additionally, there are societal concerns about the possibility of limited access to the benefits of nanomedicine by marginalized people groups locally and internationally54.
Most ethicists and researchers agree that such emerging biotechnologies, when used for therapeutic purposes, have the potential to greatly benefit patients and society as a whole. However, vastly different ethical stances become apparent when the suggestion is made that brain-to-computer-to-body part prostheses should be used in order to replace normal body parts for the express purpose of athletic enhancement or any other type of competitive endeavor. Some strongly object to the use of nanotechnology combined with cybernetics in order to completely reprogram the brain with artificial intelligence or some predetermined enhancement in healthy individuals46. These types of bodily modifications are considered radical rather than routine enhancements because they involve the "alteration of some system/process, or introduction of some novel system/process, that augments some core biological capability significantly beyond the range of capacity attainable by technologically unassisted human beings or introduces a capacity not had by technologically unassisted human beings."55 Sandler suggests that these types of enhancements get at "the kind of creature that we are" and that the ethics of radical human enhancement concern the type of creatures that we ought (or want) to be55. Discussions regarding enhancement at this level raise questions regarding what it means to be human or to be an individual person. The answers to these questions are highly variable and dependent on one's world view, values, and beliefs. There are ethicists who believe that humans are embodied spirits made in the image of God, whereas others suggest that humans are a spiritless complex construct of biomechanical systems and biochemical processes.
Some researchers who support the use of biotechnologies for enhancement of normal human characteristics and traits are associated with transhumanistic philosophy. Transhumanism is somewhat of an extreme but not uncommon philosophical extension of secular humanism. It places preeminence on personal autonomy combined with biotechnology in order to achieve radical extension of life, complete eradication of disease and suffering, and the augmentation of human intellectual, physical, and emotional capacities56. Sensory modalities and sensibilities as well as mood, energy, and self-control can be controlled supposedly by enhancement technologies. Nick Bostrom, a transhumanist philosopher, expounds evolutionary ideas that propose that we are transitional humans, "a work-in-progress, a half-baked beginning that we can learn to remold in desirable ways."56 He suggests the use of biotechnology primarily, but also by any other "rational means" in order to essentially re-create humanity and "become posthuman beings with vastly greater capacities than present human beings have."56 However, not all enhancement proponents are transhumanists. Those in favor of radical enhancement emphasize the prospective benefits of biotechnological enhancement and argue that radical enhancement is no different from other research programs that are widely accepted (e.g., hybridization, in vitro fertilization, and vaccinations)57.
Opponents of biotechnological enhancement are concerned that radical enhancement initiatives involve human design, intention, purpose, and control. They question the wisdom of trying to enhance or unnaturally tamper with what is believed to be ordained by God or nature58. Critics of enhancement biotechnology also raise unanswered questions regarding the use of such biotechnology for enhancement rather than therapeutic purposes. The side-effect and safety issues that have been associated with the use of these biotechnologies for therapeutic purposes are no less relevant when discussing the use of biotechnologies for enhancement. Furthermore, given the fact that these technologies have not been long lived or studied, informed consent issues may arise because all of the potential adverse health effects are not known. Another potential problem requiring clarification is in reference to who would be responsible for answering the complex regulatory questions of these biotechnologies. Should parents ever be required or have the legal right to radically enhance their children? Could the military require radical enhancement of soldiers? How should radical enhancement be regarded or regulated in different competitive domains (e.g., sports or job market)59? Moreover, critics believe serious consideration needs to be given to the realistic potential for accidents and improper usage of such potentially powerful technologies41. Finally, there is continuing disagreement as to what, if any, therapeutic technologies should be used for enhancement. Some who oppose the use of therapeutic biotechnology for human enhancement believe that such practices are inconsistent with traditional medical professionalism and the ultimate purpose of medical practice. Ethicist Ben Mitchell has written: "Whether we call it healing, wellness, or shalom, the goals of medicine are restorative and preventive."60 There is also concern among some medical professionals that their "right of conscience" may be challenged if they are asked to perform enhancement procedures that they consider to be morally wrong or harmful to the patient61.
Emerging biotechnologies have the potential to provide great therapeutic benefit. However, when these biotechnologies are used to enhance some aspect of an impaired or healthy individual's performance beyond normal, they are associated with new and morally challenging ethical concerns. These moral issues are new in that the practice of medicine has traditionally been for preventive or therapeutic purposes and not offered as a marketable commodity for enhancement purposes. These issues are challenging due to the wide diversity of values-based opinions on the acceptability of enhancement-driven biotechnologies that could reconfigure the method and purpose of medical practice.
Orthopaedists are stakeholders in the development and proper use of biotechnologies. They also have dual roles, as both scientists and care-giving professionals, in these ethical discussions. As such, they should be aware of the ethical implications of newer biotechnologies and also prepare themselves for the need to navigate the unexplored ethical terrain associated with the moral acceptability of these technologies, whether those technologies have been established as scientifically possible and valid or not.
Note: The author thanks Michael Sleasman, PhD, of the Center of Bioethics and Human Dignity, and Julie Ross Lea for their editorial assistance and review.
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