tribological applications of biomaterials: an overview · 2017-10-27 · vol. 44 supp. science in...

Vol. 44 Supp. SCIENCE IN CHINA (Series A) August 2001

Tribological applications of biomaterials: an overview

Bing Shi & Hong Liang

Department of Mechanical Engineering, University of Alaska Fairbanks, Fairbanks, AK, USA

Received July 5, 2001

Abstract Tribological research is the study of lubrication, friction, and wear. Tribology of biomate-rials is to study how the materials work and fail. This will help us to produce better biomaterials.Tribology plays a very important role in improving the design and making successful biomaterialsfor medical purposes. Joints of human body, such as hip, knee, jaw, dental parts etc., all need toconsider the wear and lubrication problem. In this paper, we give a general introduction of bioma-terial research in tribological applications. Materials, the synthetic characterization, and their failureare introduced.

Keywords: Biomaterials, Tribological Materials.

The earliest successful implants were bone plates, introduced in the early 1900s to stabilize

bone fractures and accelerate their healing. As early as in the late 1950s, the first total hip re-

placement was introduced using polytetraflouroethylene (PTFE) as the cup bearing surface[1].

However, the PTFE undergoes aseptic loosening.

Early in late 1960s, tribology was introduced into the living and artificial human joints[2]. The

development has been seen in many areas. For examples, the tribological behavior of synovial

joints and their replacement, wear of human dental tissues, the lubrication by plasma of red blood

cells in narrow capillaries, the wear of replacement heart valves, the wear of screws and plates in

and on bone in fracture repair, the tribology of skin and the friction of hair, biosensors, artificial

fingers, etc., are all the topics of study.

In the late 1970s, a temporomandibular joint (TMJ) replacement using PTFE as the bearing

counterface was invented. In 1983, the PTFE implant, which was called the Interpositional Im-

plant (IPI), was approved to the market. Because PTFE exhibits a low coefficient of friction and

has been used extensively as a bearing surface in other engineering applications, it would seem an

appropriate choice for an implant material in theory, However, of the more than 25,000 PTFE

TMJ implants received by patients, most failed. With the development of the research on IPI, evi-

dence did exist that PTFE was not an appropriate implant material[1].

It is estimated that 85 to 95% of approximately 600,000 total joints are performed each year

in the United States (More than 120,000 artificial hip joints are being implanted annually) will still

be functioning after ten years, based on research reported in orthopedic medical journals[3, 4]. Arti-

ficial joint replacement is performed when the cartilage that lines the joint deteriorates, resulting

in bones grinding against each other (shown in Fig. 1)[5]. If non-surgical treatments, such as

anti-inflammatory drugs, walking aids, and support braces do not offer relief.

298 SCIENCE IN CHINA (Series A) Vol. 44

Joint replacement surgery is most commonly performed

for hips, knees, and shoulders(See the joint replacements in Fig.

2)[5], although toes, fingers, and elbows have been successfully

replaced. Most artificial joint replacements are designed to re-

move the diseased areas of the joint and replace them with

metal- and-plastic implants designed specifically to restore that

joint's function and stability.

For biomaterial design, engineers must consider the

physiologic loads to be placed on the implants sufficient struc-

tural integrity. Material choices also must take into account

biocompatibility with surrounding tissues, the environment and

corrosion issues, friction and wear of the articulating surfaces, and implant fixation either through

osseointegration (the degree to which bone will grow next to or integrate into the implant) or bone

cement. One of the major problems plaguing these devices is purely materials-related: wear of the

polymer cup in total joint replacements. A summary of tribo-biomaterials was introduced in Table

1.

Fig. 2. Joint replacements.

Table 1 Summary of Tribo-biomaterials

Material Application Major Properties Description

Alloy: Titanium Alloys[6], Titanium Alumi-num Vanadium Alloy[7], Cobalt ChromiumAlloy[8], Cobalt Chromium Molybdenum

Alloy[9]

Total joint replacement Wear and corrosion resistance

Inorganic: diamond-like carbon, Biocompatible coatings,Reduced friction and increased wear resis-

tance

Ceramics[10]: Al2O3, ZrO2, Si3N4, SiC, B4C,quartz, bioglass(Na2O-CaO-SiO2-P2O5),

sintered hydroxyapatite (Ca10(PO4)6(OH)2)Bone joint coating Wear and corrosion resistance

Polymers: Ultrahigh molecular weight poly-ethylene,

Polytetraflouroethylene (PTFE)

Poly(glycolic acid)

Joint socket

Interpositional Implanttemporomandibular

joint(Jaw)Joint bone

Wear and corrosion resistanceLow coefficient of friction

Elastic with less wear

Composites: Specialized silicone polymers Bone joint Wear, corrosion, and fatigue resistance

Fig. 1. Knee joint deteriorate.

Supp. TRIBOLOGICAL APPLICATIONS OF BIOMATERIALS: AN OVERVIEW 299

As advances have been made in the medical sciences, aging population has become impor-

tant. More organs, joints, and other critical body parts will wear out and must be replaced if peo-

ple are to maintain a good quality of life. Biomaterials now play a major role in replacing or im-

proving the function of every major body system (skeletal, circulatory, nervous, etc.). Some

common implants include orthopedic devices such as total knee and hip joint replacements, spinal

implants, and bone fixators; cardiac implants such as artificial heart valves and pacemakers; soft

tissue implants such as breast implants and injectable collagen for soft tissue augmentation; and

dental implants to replace teeth/root systems and bony tissue in the oral cavity.

1 Synthesis and characterization

Biomaterials used to date, as mentioned earlier, are metals, ceramics, polymers, composites,

and biopolymers. The first four classes are conventional methods adapted from traditional materi-

als processing. The biopolymers, on the other hand, involve materials synthesis and bioengineer-

ing. There are three basic approaches: DNA linked material building, tissue culture, and biopoly-

merization.

Recently, scientists developed a method to link DNA to gold, a noble metal[11]. There are bio-

chemical approaches to molecular structures of precisely defined dimensions ranging from 1 nm

to 10 cm in length. Conversely, the synthesis of precisely defined unnatural molecular archi-

tectures beyond 25 nm in length is often unattainable due to solubility, material through-put, and

characterization constrains[12]. Therefore, as nanotechnological needs advance, syntheses could

rely upon self-assembling strategies using natural scaffolds as templates for the construction of

synthetic nanostructures[13]. Most studies involving DNA self-assembly have focused on the du-

plex interactions between complementary DNA strands, the insertion of synthetic units through

covalent tethering to specific nucleotides involving the assembly of materials through electrostatic

interactions on the phosphate groups along a DNA backbone[14].

The goal of tissue culture is to develop a synthetic alternative to orthopedic tissues such as

bone, ligament, and cartilage. Once implanted, the presence of cells and growth factors will initi-

ate bone regeneration throughout the 3-D pore

network.As regeneration continues, the matrix is

slowly resorbed by the body. Upon complete deg-

radation, the implant site is filled with newly re-

generated bone and free of any residual polymer.

Examples are given about tissue enginereered bone

(shown in Fig. 3), tissue engineered ligament

(shown in Fig. 4), tissue engineered cartilage

(shown in Fig. 5), and Cell Culture (shown in Fig.

6)[15]. In studies examining cell growth on these

matrices, osteoblast cell lines have been utilized asFig. 3. Tissue engineered bone.


well as bone cells isolated from rat calvaria to

create model systems for cell growth on bio-

erodable materials. This image shows os-

teoblasts growing on the surface of the 3-D

microsphere matrix. It is interesting to note that

the cells are growing in a circumferential pat-

tern due to the structure of the matrix.

Biopolymerization has been used to gen-

erate intelligent and smart materials. Very often

one can find them in sensoring and electronic

devices.

Fig. 5. Tissue engineered cartilage. Fig. 6. Cell culture.

Materials characterization methods are mechanical testing, chemical analysis, microstructural

characterization, explant analysis, coatings evaluation, development of special test techniques and

component design and analysis include structural analysis, reliability and probabilistic modeling,

engineering design optimization, failure analysis. Characterization is particularly difficult when

the materials are used for human body that needs in vivo test conditions.

An atomic force microscope (AFM) image is widely used in materials analysis at nanometer

scale[16, 17]. It is also used in biomaterial research. Fig. 7 is an AFM image, which shows the sur-

face structure of a hydrated Staphlococcus epidermis biofilm formed on an implant surface[18]. The

channels observed are believed to provide nourishment that sustains the biomaterials-associated

infection. Using an AFM, cortical bone is imaged at ultrahigh magnification (shown in Fig. 8)[19].

Advanced in situ microscopy testing devices allow biomaterials and biological materials to be

observed at high magnification with the AFM while being subjected to controlled levels of stress

or deformation.

Scanning electrochemical microscopy (SEM) is used to characterize the reaction rate and ion

release imaging modes of metallic biomaterials[20]. The scanning potential microscope (SPM) can

Fig. 4. Tissue engineered ligament.


also be used in measuring the micro-corrosion processes on metallic biomaterial surfaces. The

SPM has imaged localized preferential corrosion areas on the samples. Localized corrosion poten-

tial is clearly associated with topographic features[21].

Fig. 7. AFM image of a hydrated. Fig. 8. AFM image of bone Staphlococcus

epidermis biofilm.

Confocal laser-scanning microscopy (CLSM) is a rapidly advancing technique used to pro-

duce crisp and precise images of thick specimens in fluorescent and reflective light modes by re-

jection of out-of-focus light via a confocal pinhole. This feature of confocal microscopes, known

as optical sectioning, makes it possible to scan a sample at various x-y planes corresponding to

different depths, and, by ordering these planes into a vertical stack, reconstruct a three-dimen-

sional image of the specimen. Because it does not require physical sectioning of thick samples,

and precludes the need for extensive specimen processing, CLSM is one of the most efficient

methods available to gain three-dimensional information on living biological specimens and bio-

materials.

Auger electron spectroscopy (AES) is then used to identify and quantify calcium and phos-

phate, the major inorganic components of bone. The deposited mass depends on the surface

chemistry and a clear correlation between surface pretreatment and calcium/phosphate ratios is

observed. This can in some cases also be correlated to macroscopic properties such as the surface

wetability[22].

Materials Scientists continue to develop novel surface modifications to enhance textile per-

formance. Wettability is one important characteristic of a surface. Wettability of textile fibers can

be enhanced to assist the dyeing operation during processing; and the fibers can be made to be

wettable for application in, for example, materials of tissue culture.

Wear test is a basic method to evaluate the durability of biomaterials. Pin-on-disc experi-

ments are carried out on different material combinations using systematically varied tribological

conditions (lubrication, loading, contact geometry, sliding speed). Novel candidate materials will

be investigated, as well as current materials (UHMWPE) that have been modifies by different

methods (e.g. plasma technology, microfabrication, and polymer processing). The chemical and


structural properties of the tested materials and wear products are characterized by spectroscopic

and microscopic analysis techniques. Results from multi-axial joint simulator experiments, as well

as analysis of components from retrieved clinical implants constitutes references for the in vitro

simulation studies.

The material properties and the mechanical and electrochemical processes were observed to

control the corrosion attack to the hip replacement. Some electrochemical tests methods list as

following, Short term tests: the effect of cyclic load magnitude on fretting corrosion currents;

Long term tests: rest tests, cyclic mechanical loading, scratch test, etc[7, 8, 9].

Artificial mechanical heart valves are made of pyrolytic carbon to prevent complications as-

sociated with blood clotting, but this material can be subject to cyclic fatigue. An acoustic emis-

sion-based system is developed for detecting crack initiation and the growth of existing flaws

during controlled stress testing of artificial heart valves.

2 Tribological applications and failure

The properties of biomaterials to date still do not meet the application requirements. The part

of many potential causes of failure for the total hip arthroplasty, for example, is[23] deficiencies in

design (size and shape) of the device for a particular patient (e.g., an undersized noncemented

stem); surgical problems (e.g., problematic orientation or problems in wound healing); host ab-

normalities or diseases (e.g., osteopenia); infection; and material fracture, wear, and corrosion[11].

Synovial joints, including the knee joints, are typically found at the ends of long bones and

permit a wide range of motion[24]. This type of joint is surrounded by a fibrous articular capsule,

which is lined by a thin synovial membrane. It is important to note that the surfaces of each bone

are not in direct contact, but are covered by special articular cartilages, which resemble the hyaline

cartilages found elsewhere in the body.

The synthetic biomaterials, such as stainless steel, titanium alloy, polymers, and ceramic

composite, undergo degradation through fatigue and corrosive wear due to load-bearing and the

salty environment of the human body. At the same time, deposits of inorganic salts can scratch

weight-bearing surfaces, making artificial joints stiff and awkward. The lifetime of an implant is,

at most, 10 to 15 years.

Using the methods previously mentioned, the failure mechanisms reported are discussed with

a few examples.

Fracture happens often in bone and orthropedic implants when load-bearing ability is impor-

tant. Once fractured, biomaterials cannot be regenerated as nature bones. Therefore, structure and

properties are particularly important here. It is also very important to induce lubricants to improve

the biomaterial properties in the same time. The inducing of the lubricants could reduce the wear,

which is one of the main problems that could lead to fracture of the materials. Some research

works have been done in investigating the lubricant thin film’s failure[25, 26].

Wear of the articulating surfaces in artificial hip and knee joints gives rise production of wear


particles of sizes of submicrons and larger. The negative biological effects of these wear particles

are considered to be one important factor that limits the long term clinical performance of this

type of devices. There is therefore an immediate need for development of novel and improved

material combinations for the articulating surfaces in artificial joints. Such development is in turn

dependent on an improved understanding of the wear processes involved and how these are influ-

enced by different material properties and conditions. Equally important is it to develop reliable

and predictive methods for stimulating the wear processes under in vitro conditions, preferentially

in an accelerated way.

In order to provide a basis for systematic development of novel material combinations and

surfaces with improved wear properties and to develop reliable in vitro screening methods for as-

sessing the wear of different candidate combinations, the wear research is done to obtain an in-

creased understanding of the mechanisms underlying wear in artificial joint protheses. The long

term engineering goal is to develop a material (surface) combination which does not produce bio-

logically harmful wear particles under the physiological conditions that prevail in artificial hip and

knee joints.

A total hip replacement is clinically successful with most designs that utilize an ultrahigh

molecular weight polyethylene (UHMWPE) acetabular surface articulating with either a metallic

or ceramic femoral head component[27]. However, aseptic loosening, often accompanied by oste-

olysis, continues to be a source of long-term clinical failure. It was suggested that the macrophage

response to phagocytosis of particulate wear debris, occurring in interaction between the cement

and bone, was an important causative factor in osteolysis, leading to eventual loosening[28]. The

particulate debris has emerged as a major factor in the long-term performance of joint replacement

prostheses[29]. When present in sufficient amounts, particulates generated by wear, fretting, or

fragmentation induce formation of an inflammatory, foreign-body granulation tissue that has the

ability to invade the bone-implant interface[30�37]. This may result in progressive periprosthetic

loss of bone, a loss that threatens the fixation of prostheses inserted with or without

cement[12, 38, 39].

Studies of wear debris extracted from actual tissue samples of patients whose implants failed

as a result of aseptic loosening have generated significant information regarding wear particle size,

shape, and surface morphology. AFM was used to produce detailed, high resolution images of

wear particles, few hundred nanometers in size. Wear debris studied sometimes exhibits a cauli-

flower-like surface morphology. By combining wear debris and cellular response studies, engi-

neers and biologists will be able to better understand implant failure and to re-engineer implants to

prevent future problems

The wear problem that occurs with an artificial joint implant component (socket) constructed

of UHMWPE is illustrated in Fig. 9. At left is unworn UHMWPE. The sample at right has under-

gone a friction and wear test versus cobalt chromium (artificial joint ball material). The fibrillation

and small particles are characteristic of an adhesive wear mechanism, which can result in sur-


rounding bone loss and the need for implant replacement[1].

Fig. 9. SEM micrographs of socket of UHMWPE before and after wear test(20,000X).

Corrosive attack in the taper crevice of modular implants made of similar metals or

mixed-metals combinations[40�44]. The corrosive attack results in metal release and mechanical

failure of the component[45]. Corrosive fatigue, on the other hand, is expected due to cyclic loading

and the corrosive environment of human body. The fractures occurred at the grain boundaries of

the microstructure and appeared to be the result of three factors: porosity at the grain boundaries;

intergranular corrosive attack, initiated both at the head-ceck taper and at free surface; and cyclic

fatigue-loading of stem[46].

3 Summary

Biomaterials are the future of the medicine. From tissue removal, replacement, to future re-

generation, biomaterials will take part the most advancement in the near future. Biomaterials and

implant research will continue to concentrate on serving the needs of medical device manufactur-

ers and recipients, as well as medical professionals. Development of technologies will meet those

needs by designing the materials in strength, shape, function, and behavior. Future biomaterials

will incorporate biological factors (such as bone growth) directly into an implant’s surface to im-

prove biocompatibility and bioactivity. New projects will be directed at materials development for

improved mechanical integrity, corrosion resistance, and biocompatibility. The understanding of

the nature of the human body parts like knee, jaw, dental parts, and hip, etc., will lead to the ap-

plying of these techniques in future materials design.

References

1. Cheryl, R., B., Biomaterials: Body Parts of the Future, Technology Today, Fall 1995 issue, Southwest Research Institute.

2. Dowson, D., Prgress in Tribology: A historical Perspective, New Directions in Tribology, (ed. Hutchings, I. M.) London:

First World Tribology Congress, 8-12 Sept., 1997. 3�20.

3. McLaughlin, J, 8-10 Year results using the taperloc femoral component in uncemented total hip arthroplasty, Presented at

the Annual Meeting of the American Academy of Orthopedic Surgeons, February, 1994.

4. Ritter, K. et al., Flat-on-Flat, Nonconstrained, Compression molded polyethylene total knee replacement, Clinical

Orthopedics and Related Research, December, 1995, 321: 79�85.


5. http://www.biomet.com/patients/bestimplant.html.

6. Long M., Rack, H., Review, titanium alloys in total joint replacement��A Materials Science Perspective, Biomaterials,

19: 1998, 1621�1639.

7. Gilbert, J. L., Jacobs, J. J., The mechanical and electrochemical processes associated with taper fretting crevice cososion:

A review, modularity of orthopedic implants, ASTM STP 1301 (eds. Marlowe, D. E. Parr, J. E. Mayor, M. B.), American

Society for Testing and Materials, 1997, 45�59

8. Gilbert, J. L., Buckley, C. A., Mechanical-electrochemical interactions during in vitro fretting corrosion tests of modular

taper connections, Total Hip Revision Surgery (eds. Galante, J. O. Rosenberg, A. G. Callaghan, J. J.) New York: Raven

Press, Ltd., 1995.

9. Goldberg, J. R., Gilbert, J. L., Electrochemical response of CoCrMo to high-speed fracture of its metal oxide using an

electrochemical scratch test method, J. Biomed. Mater. Res, 37, 421�431, 1997.

10. Sarikaya, M. Fong, H. Frech, D. et al., Biomimetic assembly of nanostructured materials, Materials Science Forum, Vol.

1999, 293: 83�98.

11. Wu, C., DNA links gold into new materials, Science News, 1996, Vol. 150, Aug. 17.

12. Tour, J. M., Chem. Rev., 96, 537�553, 1996. G.M.Whitesides, J. P. Mathias, C. T. Seto, Science, 1991, 254: 1312�1319.

13. Niemeyer, C. M., Chem. 109, 603�606, 1997, Angew. Chem. Int. ed. Engl. 36, 585-587, 1997, (b) C.A.Mirkin, R. L.

Letsinger, R.C. Mucic, J.J. Storhoff, Nature, 382, 607-609, 1996; (c) A.P. Alivisatos, K. P. Johnsson, X. Peng, T.E. Wilson,

C.J.Loweth, M.P.Bruchez, P.G.Schultz, Nature, 382, 609-611, 1996, (d) J.Chen, N.C. Seeman, Nature, 350, 631-633, 1991;

(e) Seeman, N.C. Acc. Chem. Res., 30, 357�363, 1997.

14. Bach, D., Miller, I. R., Biochim. Biophys. Acta, 114, 311�325, 1966; (b) I.R. Miller, D. Bach, Biopolymers, 6, 169-179,

1968, (c) P.L. Felgner, T.R. Gadek, M. Holm, R. Roman, H.W.Chan, M.Wenz, J.P. Northrop, G.M. Rigold, M.Danielsen,

Proc. Natl. Acad. Sci. USA, 84, 7413, 1987; (d) H.J.Vollenweider, J.M.Sogo, H.H.Koller, Proc. Natl. Acad. Sci. USA, 72,

83�87, 1975.

15. http://laurencin.coe.drexel.edu/

16. Lu, X. C., Shi, B., Luo, J. B. et al., Investigation on microtribological behavior of thin films using friction force micro-

scope, Suface & Coating Technology, (2000) 128�129: 341�345.17. Lu, X. C. Wen S. Z. ed al., A friction force microscope employing laser beam deflection for force detection, Chinese Sci-

ence Bulletin, 1996, 41(22): 1873�1876.

18. http://www.swri.org/3pubs/brochure/d06/matstruc/msadd1g.htm.

19. http://www.swri.edu/3pubs/brochure/d10/appbiom/appbiom.htm.

20. Gilbert, J. L., Smith, S, M., Lautenschlager, E. P. Scanning electrochemical microscopy of metallic biomaterials: reaction

rate and ion release imaging modes, J of Biomed mater res. 1993, 27: 1357�1366.

21. Smith, S. M., Gilbert, J. L., The scanning potential microscope: an instrument to image micro-corrosion process on metal-

lic biomaterials surfaces, Winter, 2(2): 11�16.

22. Håkan Nygren, Pentti Tengvall, Ingemar Lundström, The initial reactions of TiO2 with blood, J. Biomed. Mater. Res.,

1997, 34: 487�492.

23. Spector, M. Biomaterial Failure, Orth. Clin. N. Am., 23, 2, April, 211-217, 1992.

24. L.L. Woodruff and G.A. Baitsell, Foundations of Biology, The Macmillan Company, NY, 1951

25. Luo, J. B., Liu, S. Shi, B. et al., The failure of nano-scale liquid film, Inter. J. of Nonlinear Sci. and Num. Simu., 2000, 1:

419�423.

26. Luo Jianbin, Qina Linmao, Wen Shizhu et al., The failure of fluid film at nano-scale, STLE, Tribology Trans., 1999, 42(4):

912�916.

27. Wang, A. Essner, A. Polineni, V. K., D.C. et al., Dumbleton, lubrication and wear of ultra-high molecular weight polyeth-

ylene in total joint replacement, New Directions in Tribology, (ed. Hutchings, I. M.) World Tribology Congress, London,

443�458, 1997.

28. Willert, H. G., Semlitsch, M., Reactions of the articular capsule to wear products of artificial joint prostheses, J. Biomed.

Mater. Res., 1977, 11: 157�164.


29. Urban, R. M., Jacobs, J. J., Gilbert, J. L. et al., Migration of corrosion products from modular hip prostheses, J. Bone and

Joint Surgery, 1994, 76(9): 1345�1359.

30. Amstutz, H. C., Campbell, P., Kossovsky, N, et al., mechanisms of clinical significance of wear debris-induced osteolysis,

Clin. Orthop., 1992, 276, 7�18.

31. Boss, J. H., Shajrawi, I., Soundry, M. et al., Histomorphological reaction patterns of the bone to diverse particulate implant

materials in man and experimental animals, particulate debris from medical implants: Mechanisms of formation and

bilogical consequences, ASTM STP 1144, 90�108 (eds..St. John, K. R.), Philadelphia, American Soc. Testing and Matls.,

1992.

32. Dicarlo, E. F., Bullough, P. G., The biologic response to orthopedic implants and their wear debirs, Clin. Mater., 1992, 9:

235�260.

33. Kossovsky, N., Mirra, J. M., Biocompatibility and bioreactivity of arthroplastic matls., Hip Arthroplasty, 571�601, (ed.

Amstutz, C. New York: Churchill Livingstone, 1991.

34. Mirra, J. M., Amstutz, H. C., Matos, M. et al., The pathology of the joint tissues and its clinical relevance in prosthesis

failure, Clin. Orthop., 1976, 117: 221�240.

35. Pizzoferrato, A., Ciapetti, G., Stea, S. et al., Cellular events in the mechanisms of prosthesis loosening., Clin. Mater., 1991,

7, 51�81.

36. Spanier, S., Histology and pathology of total joint replacement, total joint replacemnt, 165�185, (eds. Petty, W.) Phila-

delphia: W.B. Saunders, 1991.

37. Willert, H. G., Bertram, H., Buchhorn, G. H., Osteolysis in alloarthroplasty of the hip, Clin. Orthop., 1990, 258: 95�107.

38. Nyquist, R. A., Kagel, R.O., Infrared Spectra of Inorganic Compounds, New York: Academic Press, 1971, 171.

39. Willert, H. G., Failure modes of artifical joint implants due to particulate implant material, Implant Bone Interface (ed..

Older, J.) New York: Springer, 1990.

40. Buckley, C. A., Gilbert, J. J., Urban, R. M. et al., Lautenschlager, mechanically assited corrosion of modular hip prosthesis

components in mixed and similar metal combinations, Trans. Soc. Biomater., Implant Retrieval Symposium, 15, 58, 1992.

41. Collier, J. P., Surprenant, V. A., Jensen, R. E. et al., Mayor, Corrosion at the interface of cobalt-alloy heads on tita-

nium-alloy stems., Clin. Orthop., 1991, 271: 305�312.

42. Collier, J. P., Surprenant, V. A., Jensen, R. E. et al., Surprenant, corrosion bet. the compnents of modular femoral hip pros-

theses, J. Bone and Joint Surg., 74-B (4), 511�517, 1992.

43. Gilbert, J. L., Buckley, C. A., Jacobs. J. J. R. et al., Mechanically Assisted Corosive Attack in the Morse Taper of Modular

Hip Prostheses, Trans. 4th World biomtls. Congress, 267, Berlin, Euro. Soc. Biomtls., 1992.

44. Mathiesen, E. B., Lindgren, J. U., A.Blomgren, G. G. et al., Corrosion of modular hip prostheses, J. Bone Jnt. Surg.,

73-B(4), 569�575, 1991.

45. Urban, R. M. Jacobs, J.J. Gilbert, J. L. et al., Corrosion prodcuts of modular hip prostheses: Micromechanical identifica-

tionand histopathological significance, Trans. Orthop. Res. Soc., 18, 81, 1993.

46. Gilbert, J. L. Buckley, C. A. Jacobs, J. J. et al., Intergranular corrosion-fatigue failure of cobalt-alloy femoral stems, J.

Bone Jnt. Surg., 76-A (1), 110�115, 1994.

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