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ETHICAL ISSUES WITH BIOMATERIALS IN ORTHOPEDIC
ENGINEERING
Christen Kraemer (cek59@pitt.edu)
INTRODUCTION: ETHICS AND
BIOMATERIALS USED IN ORTHOPEDICS
Tissue Engineering
Engineers are working on advancements for sports
injuries that help the body repair itself instead of replacing or
impersonating the injured area [1]. This would be very helpful
in sports medicine because it would allow the injured player
to return to their sport quickly and not have to worry about
rejection of the materials used in the artificial repair. This idea
of the body repairing itself using tissue engineering can also
be helpful for cartilage damage. The article “Biomaterials in
the repair of Sports Injuries” discusses how cartilage damage
can be treated. “Lesions to cartilage, typical in highperformance sports, are notoriously more difficult to treat
than bone fractures. This is mostly because of the nature of
the tissue itself, namely, that it is very dense, has low
cellularity and is almost completely avascular in the adult”
[1]. This means that the cartilage is difficult to get to and even
harder to manipulate. One way engineers have tried to
overcome the low cellularity is by using the subchondral bone
plate [1]. The subchondral bone plate is utilized to send
cellular marrow elements to the site of cartilage repair [1].
This can be helpful because the clot stabilizes and forms
fibrous and cartilaginous tissue but it cannot produce full
hyaline cartilage which is normally found between bone
plates [1]. To improve on this procedure, engineers have tried
to add scaffolds that could help delineate the new tissue as
hyaline cartilage but have not had success thus far [1].
Another way engineers have tried to repair damaged
cartilage is to directly deliver chondrocytes or chondrocyte
precursor cells to the area of damage [1]. These cells are
known to produce hyaline cartilage matrices instead of the
general cartilage and fibrous tissue [1]. This procedure is
slightly more difficult because the chondrocytes must be
isolated from an area away from the damage, and taken from
the body to be regrown and then reimplanted where the
damage occurred [1]. Generally, this procedure has a higher
success rate than using the subchondral bone plate [1].
Engineers are continuing to improve this procedure by adding
stabilizing biomaterials before reimplanting which can help
grow stronger and larger amounts of cartilage [1]. This type
of procedure would be more ethically sound because it uses
the patient’s own chondrocytes instead of taking stem cells
and differentiating them into chondrocytes.
People are living longer and many western countries like
the US are experiencing an aging population. However,
limited financial resources are available to serve the entire
population needs for biomaterials to increase mobility,
decrease pain and overall improve life. It is believed that an
individual’s general health level is directly linked to their
ability to keep physically active. Therefore, I believe that it is
important for Bioengineers to continue research and
development efforts to find longer lasting biomaterials,
improve procedures and techniques to lead to more cost
effective solutions. Over 300 years ago, scientists and doctors
realized they could use cells as a means to improve tissue
damage [4]. This was shown in the first attempt of a bone graft
in 1668 by Job-Van Meek’ren, the Dutch surgeon [4].
There are many ethical issues that arise when orthopedic
cases require the use of biomaterials. This past December, I
had surgery to repair my labrum and am now in a situation in
which ethical issues arise. The surgery I had was for a SLAP
tear that I acquired playing tennis. The SLAP,superior labrum
anterior and posterior, “aids in cavity-compression,creating a
seal around the humeral head, and augments glenohumeral
stability,” as stated in Sports Medicine Update [11]. The
labrum sits in the glenoid cavity around the humeral head to
hold it in place. When there is a tear, the labrum is not
attached to the glenoid anymore and therefore cannot hold the
humerus in place. I had a Type IIC tear meaning, “Labrum
and biceps anchor point detached from superior rim of
glenoid…with combined anterior and posterior extension,”
[11]. Further explained, I tore my labrum on the front and
back of my shoulder around the bicep tendon connection. My
last surgery failed and now I can make a choice between
another repair using Labraltape or tissue engineering. These
two options bring about different ethical issues. With tissue
engineering, the main ethical issue is stem cell usage. The use
of stem cells is a very controversial topic because stem cells
can only be obtained from a fetus. The fetus can be human or
xenogenic [2]. If the stem cells are obtained from human
embroyonic cells, a very large ethical issue comes to mind.
When the stem cells are obtained from a human embryo, the
fetus is destroyed in the process. Xenogenic, animal or plant
stem cells, raise another ethical issue about species boundary
[2]. When xenegenic stem cells are used, the product is part
human and part plant or animal [2]. This is an ethical issue
because it is combining the tissues of two species and creating
a not entirely human person and in some sense the doctor and
engineers are “playing God.”
Ethical Issues with Tissue Engineering
Tissue engineering is obviously a large ethical issue
because generally, the stem cells used in tissue engineering
are harvested from a human fetus. When the stem cells are
University of Pittsburgh Swanson School of Engineering
2013-10-01
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Christen Kraemer
harvested, the fetus is destroyed. This breaks the code of
ethics for engineers when it says, “Engineers shall hold
paramount the safety, health, and welfare of the public” [6].
Destroying the fetus is obviously a breach of this because the
engineers are not concerned with the safety or health of the
fetus. Some people do not agree that this is an ethical issue
because they believe a fetus does not have life yet. Most
religions agree that life begins at the moment of conception,
therefore destroying a fetus is murder. Science also agrees
that the fetus has life, just the same as a developed baby [8].
Since murder is a felony this technically makes the engineers
or doctors who destroy the fetus for the use of the stem cells,
criminals. Considering that abortion is legal in our country
and the choice of the woman, this is not currently the public
opinion.
Part of the Biomedical Engineering Society Code of
Ethics states “Consider the larger consequences of their work
in regard to cost, availability, and delivery of health care” [7].
To me, tissue engineering breaks this aspect of ethics as well.
Some people may believe that the consequences of destroying
the fetus are outweighed by the reward of being able to help a
patient, especially in extreme cases of tissue engineering
where it is used to assist people with life threatening illness,
such as leukemia. In my opinion, the killing of the fetus is not
worth the risk of tissue engineering. Nothing is guaranteed to
work in tissue engineering and not allowing a human their life
is much more of a consequence than finding a more ethical
solution to treating the patient.
Another main argument against the ethics of tissue
engineering using embryonic stem cells is the debate of
“personhood” [8]. Beyond the debate about when life is
indeed started, some people argue that the fetus may have life
but it does not have the qualities of being a person so it is not
unethical to kill it since it does not have rights. The Journal
of Law, Medicine & Ethics states, some qualities of a
“person” that the fetus does not have are the “ability to think,
feel and anticipate the future” [8]. Obviously a fetus cannot
do these things but in my opinion, these abilities are only
acquired with time and age so a fetus cannot be expected to
have the same qualities as an adult but it should still have the
same rights since it still has life. Some people like L.
Trommelmans and colleagues state “We suggest that viewing
tissue engineering as a new medical paradigm allows us to
develop a wider perspective for successful investigation
instead of focusing on isolated steps of the tissue engineering
process in an anecdotal way, which may lead to an inadequate
ethical evaluation” [3]. This statement shows that sometimes
the larger consequence (or reward) is more important
ethically than the steps taken to get there. This is entirely
incorrect in my opinion because I believe every step should
be considered, not just the final result.
labrum is actually very ethically sound. To repair the labrum,
platelet rich plasma is used. Platelet rich plasma is ethically
sound because all that is required is a small sample of blood
from the patient. The blood is then spun in a centrifuge to
separate the parts of the blood. The concentrated platelet rich
plasma is then injected into the affected area. The injection
brings about the body’s own response to heal the injury. This
solution is ethically sound because it does not raise either
ethical issue. Since the PRP is taken from the patient’s own
blood, it does not cross species boundaries or use embryonic
stem cells. A specific case has been studied using PRP to treat
my exact injury. A 25 year-old woman who played 7 years of
softball had a SLAP (superior labral anterior to posterior) tear
[5]. After not being helped through physical therapy, she
decided to try a new route. This new treatment was PRP
injections and it helped her greatly along with more physical
therapy [5].
A possible ethical solution to tissue engineering would be
using adult stem cells. Using adult stem cells raises another
issue; not of ethics but of functionality. Adult stem cells can
be harvested from bone marrow or through a specific process
of removing blood. The stem cells found in adults are not
nearly as differentiable as embryonic stem cells. Stem cells
harvested from adults can easily differentiate into similar
tissues from where they were taken but not much beyond that.
Embryonic stem cells can be differentiated into almost any
type of cell found in the body. This makes adult stem cells
very useful in some cases but in others impossible to use.
Recently another solution was thought to be found. This
solution was to use human skin cells and undifferentiated
them into induced pluripotent stem cells [5]. This was thought
to be the perfect solution because it did not use embryonic
stem cells but it is still not ethically sound because the stem
cells were being used to form life ex vivo, or again “playing
God.” It also raises the ethical question of if the bio-donors
should be compensated for their donation [5]. This violates
the code of ethics for engineers when it says, “Engineers shall
not solicit or accept financial or other valuable consideration,
directly or indirectly, from outside agents in connection with
the work for which they are responsible” [6]. This shows that
they cannot pay people to donate their skin cells. This was
abolished when blood donors stopped being paid for
donations.
Labraltape
About three months after my surgery, bioengineers
developed a new design called Labraltape. Five months postsurgery, I began to have problems with my shoulder again.
The doctors believed this trouble was due to the knot in the
suture moving laterally into my shoulder joint. Later, we
found out the knot had actually unraveled and was no longer
holding my labrum in my glenoid cavity. The new Labraltape
is 1.5 mm and uses a knotless Pushlock to reattach the labrum
[10]. This approach is much more reliable because there is no
knot to be disturbed if the patient’s body reacts like mine and
Ethical Solutions to Tissue Engineering
Using tissue engineering in the repair of labrums is a
somewhat new technique. The engineering used to repair the
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Christen Kraemer
does not cover the suture with tissue. My surgery failed but
the Labraltape that engineers designed could help many
patients including myself in the future during labral repair
surgeries.
which is being aborted anyway. This is still a debate that is
going on and probably will be for years to come due to the
different opinions on abortion.
CONCLUSION: ORTHOPEDIC
ENGINEERING ETHICS
Ethical Issues of Labraltape
Most Ethical issues do not accompany the use of
Labraltape because it is a fairly safe and effective method
which excludes human cell harvesting. The only issue could
be how the Labral tape is tested before it is used. Many
biomaterials have to go through rigorous testing before they
are allowed to be used in a surgery or procedure. Most of these
tests are physical evaluations of strength and durability. These
products also have to be tested for their biocompatibility.
Most of these tests are done in simulated conditions to follow
the code of ethics and have the sole goal the patient’s safety
and health, but the first few uses are basically tests of how the
product truly works in vivo. This could be a breach of the
biomedical engineering society code of ethics if the patient is
talked into a new procedure that does not end up working or
even ends up harming the patient. This would violate the
cannon in the Code of Ethics for Engineers that states,
“Engineers shall advise their clients or employers when they
believe a project will not be successful” [6]. Engineers bypass
this breach by telling the patients all the possible outcomes
and letting them decide.
Biomaterials can help a variety of orthopedic procedures
by helping the body learn to heal itself or by physically
repairing the damage. Although these materials are expensive
and difficult to make, the advancements are worthwhile. I
strongly believe engineers should continue the research of
biomaterials and design of materials even more efficiently.
Through continued development and production,
bioengineers strive to provide longer lasting solutions at
lower costs. The effects of successful biomaterials on sports
injuries, improved health of aging population and overall
physical wellbeing are the benefits of this biomaterial
engineering and far outweigh the costs. Tissue engineering
can be used for many different problems in today’s world,
especially orthopedics. Typically, the use of tissue
engineering comes with a few ethical issues. These ethical
issues involve the breakage of species boundaries, destroying
a fetus for embryonic stem cells and testing on humans.
Fortunately, there are solutions to these ethical issue in the
field of orthopedics. Sometimes adult stem cells may be used,
specifically from the person who needs the repair, therefore
making it entirely ethically sound. In my opinion, there are so
many options in the medical field right now for orthopedic
repair that solutions which raise ethical questions should not
even be considered. The field of bioengineering is growing,
expanding, and advancing so quickly that in a few short years,
these ethics questions may not even exist as new solutions
may be developed.
My Solution
As an engineer, my solution to the ethical issues
associated with the repair of a torn labrum would be to use the
PRP injections. Before I accept a position in the
bioengineering field, I would consider how the company
handles ethical issues and if I agree with their solutions. In my
opinion this is a very ethically sound solution that can fully
repair the labrum and is minimally invasive. This would
adhere to the Biomedical Engineering Society Code of Ethics
because it is the best solution for the health, and safety of
everyone involved. It does not involve the death of any fetus,
overlap of species, or testing of biomaterials on humans. The
lines of ethics sometimes become blurred as the decision of
what to do becomes more difficult. Although I would give
ALMOST anything to be able to play tennis again, it is very
easy to see the most ethical and best solution for me.
Thankfully in my case the most ethical and best solution are
the same. The PRP injections uphold my moral, religious and
ethical values while providing an effective and technological
solution. In other situations this may be very difficult and the
lines of ethics overlap for the patient or the patient’s family.
In a situation where the patient is suffering from a life
threatening illness, this becomes a serious debate. If the fetus
is going to be aborted anyway and the stem cells can be used
to save someone’s life, is the procedure still unethical? In my
opinion, yes, but others in the situation may disagree saying
that the benefits to the dying outweigh the damage to the fetus
References
[1] P. Ducheyne, R.L. Mauck, D.H. Smith. (2012).
“Biomaterials in the repair of sports injuries.” Nature
Materials.
(online
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[2] Brey, P. (2009). “Biomedical Engineering Ethics.” A
Companion to Philosophy of Technology. (Online Article).
http://www.utwente.nl/gw/wijsb/organization/brey/Publicati
es_Brey/Brey_2009_Biomed_Engineering.pdf
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Christen Kraemer
[3] (2010). “Research on tissue engineering reported by
scientists at Center for Biomedical Ethics and Law.” Blood
Weekly. (Online Article).
http://go.galegroup.com/ps/i.do?action=interpret&id=GALE
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[4] P. Hernigou, Y. Homma. (2012). “Tissue bionengineering
in orthopedics.” Clinical Cases in Mineral and Bone
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3392675/?to
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[5] V. R. Kraats, A. Doss. (2012). “Glenoid Labral Tear:
follow up case series on ultrasound guided autologous platelet
rich plasma in conjunction with a progressive rehabilitation
program.” (Online Article).
http://f1000research.com/articles/1-68/v1
[6] (2007). “Code of Ethics For Engineers.” National Society
of Professional Engineers. (Online Article).
http://www.nspe.org/resources/pdfs/Ethics/CodeofEthics/Co
de-2007-July.pdf
[7] (2004). “Biomedical Engineering Society Code of Ethics.”
BMES. (Online Article).
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[8] R. M. Doerflinger. (2010). “Old and New Ethics in the
Stem Cell Debate.” Journal of Law, Medicine & Ethic.
(Online
Article).
http://web.ebscohost.com/ehost/pdfviewer/pdfviewer?sid=9e
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[9] S. Lehrman. (2010). “Undifferentiated Ethics.” Scientific
American. (Online Article).
http://web.ebscohost.com/ehost/detail?sid=75a5cb2f-a2134af6-8facf1f505a96749%40sessionmgr112&vid=8&hid=125&bdata=
JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=aph&AN=5288
8702
[10] (2013). “LabralTape™.” Anthrex. (Online Article).
http://www.arthrex.com/labraltape
[11] W. N.Levine, D. J. Solomon. (2011). “Slap Tears: Pearls
And Pitfalls In Diagnosis And Management.” Sports
Medicine Update. (Online Article).
https://www.sportsmed.org/uploadedFiles/Content/Medical_
Professionals/Professional_Educational_Resources/Publicati
ons_and_Resources/Sports_Medicine_Update/SMU_2011/S
MU%20Jan%20Feb%2011%20WEB.pdf
Acknowledgements
I would like to thank the library staff for helping me
decide on a topic and Dr. James P. Bradley for giving me so
much information about my surgery and possible upcoming
surgery.
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