Journal articles: 'Total surface bearing'

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Zagra, Luigi, and Enrico Gallazzi. "Bearing surfaces in primary total hip arthroplasty." EFORT Open Reviews 3, no. 5 (May 2018): 217–24. http://dx.doi.org/10.1302/2058-5241.3.180300.

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Total hip arthroplasty (THA) is widely considered one of the most successful surgical procedures in orthopaedics. It is associated with high satisfaction rates and significant improvements in quality of life following surgery. On the other hand, the main cause of late revision is osteolysis and wear, often a result of failure of bearing surfaces. Currently, several options are available to the surgeon when choosing the bearing surface in THA (ceramic-on-ceramic (CoC), ceramic-on-polyethylene (CoPE), metal-on-polyethylene (MoPE)), each with advantages and drawbacks. Very few studies have directly compared the various combinations of bearings at long-term follow-up. Randomized controlled trials show similar short- to mid-term survivorship among the best performing bearing surfaces (CoC, CoXLPE and MoXLPE). Selection of the bearing surface is often ‘experience-based’ rather than ‘evidence-based’. The aim of this paper is therefore to evaluate the main advantages and drawbacks of various types of tribology in THA, while providing practical suggestions for the surgeon on the most suitable bearing surface option for each patient.Cite this article: EFORT Open Rev 2018;3 DOI: 10.1302/2058-5241.3.180300.

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Walker, Peter S. "Bearing Surface Design in Total Knee Replacement." Engineering in Medicine 17, no. 4 (October 1988): 149–56. http://dx.doi.org/10.1243/emed_jour_1988_017_041_02.

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Surfaces for condylar total knee replacement are designed using computergraphics techniques. An average anatomical femoral surface is represented mathematically. Mathematical equations are written to describe normal knee motion and normal laxity. Tibial surfaces are generated by placing the femur stepwise in multiple sequential positions, through a defined three-dimensional motion or laxity path. In addition, a flat tibial surface is defined, to represent the least amount of femoral-tibial conformity in currently-used knee replacements. Elasticity theory is used to calculate the maximum contact stresses at the femoral-tibial contact points. The least stresses are produced with a fixed axis cylindrical motion, while the highest are with a flat tibial surface. A surface based on laxity produces lower stresses than for normal knee motion, and is thought to be acceptable in terms of both freedom of motion and stability. Such a laxity surface is proposed as being suitable for total knee design.

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Jin, Z. M., D. Dowson, and J. Fisher. "Stress Analysis of Cushion form Bearings for Total Hip Replacements." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 205, no. 4 (December 1991): 219–26. http://dx.doi.org/10.1243/pime_proc_1991_205_297_02.

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Cushion form bearings comprise a thin layer of low elastic modulus material on the articulating surface of the bearing, which can deform to help preserve a film of lubricant between the bearing surfaces and therefore reduce friction and wear. The long-term function of this type of bearing is dependent on the strength and durability of this compliant layer. Finite difference and finite element methods have been used to analyse the stress distribution in the compliant layer of cushion form bearing for artificial hip joints under physiological loading conditions. A good agreement between finite difference and finite element methods was found. Under normal loading, the highest value of the maximum shear stress was found to be at the interface between the compliant layer and the more rigid substrate close to the edge of the contact. The values of maximum shear stress in the centre of the contact close to the articulating surface were lower than in the equivalent Hertzian contact. A friction force acting at the surface had little effect on the stress distribution for coefficients of friction less than 0.05. However, for higher values of friction coefficient (larger than 0.2), corresponding to inadequate lubrication, the maximum shear stress increased by a factor of four and was found to be located at the surface. The analysis predicts that the mode of failure will be at the interface with the substrate under fluid film or mixed lubrication conditions and at the articulating surface when the bearing runs dry with higher levels of friction. Both failure modes have been observed experimentally under the conditions specified.

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Cates, Casey A., and Michael H. Huo. "Alternative bearing surface in total hip arthroplasty." Current Opinion in Orthopaedics 16, no. 1 (February 2005): 21–24. http://dx.doi.org/10.1097/01.bco.0000151396.79069.6e.

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Sharkey, Peter F., and Michael R. Bloomfield. "Bearing Surface Failure in Total Knee Arthroplasty." Seminars in Arthroplasty 23, no. 4 (December 2012): 258–61. http://dx.doi.org/10.1053/j.sart.2013.01.009.

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Chen, Long, Fei Xing, Yuanzheng Wang, Rui He, Jingming He, Yunwen Xu, Cheng Wang, et al. "Outcome analysis of various bearing surface materials used in total hip replacement." Materials Express 10, no. 3 (March 1, 2020): 301–13. http://dx.doi.org/10.1166/mex.2020.1651.

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Since the first total hip replacement (THR) in 1938 by Philip Wiles, prosthesis materials and THR surgical technologies have developed rapidly. In this review, we use internationally-published research to synthesize a comprehensive analysis of the specific characteristics and clinical outcomes of different bearing surfaces used in THR. Polyethylene, metallic alloys, and ceramic have become the three most commonly used hip prosthesis bearing surfaces after decades of hip implant development. Different bearing surface types have varying characteristics that offer specific benefits and risks of complication. A thorough understanding of the unique properties and possible complications of each type of bearing surface is critical to surgeons tasked with selecting appropriate implant materials for total hip replacement.

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Chapman-Sheath, P., S. Cain, W. J. M. Bruce, W. K. Chung, and W. R. Walsh. "Surface roughness of the proximal and distal bearing surface of mobile bearing total knee prostheses." Journal of Arthroplasty 17, no. 6 (September 2002): 713–17. http://dx.doi.org/10.1054/arth.2002.33545.

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Zika, T., I. C. Gebeshuber, F. Buschbeck, G. Preisinger, and M. Gröschl. "Surface analysis on rolling bearings after exposure to defined electric stress." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 223, no. 5 (March 18, 2009): 787–97. http://dx.doi.org/10.1243/13506501jet538.

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This article gives an overview about classical and frequency converter-induced spurious bearing currents in induction machines and discusses typical damage patterns caused by the current passage. To investigate on the electric damage mechanisms, test bearings are operated in a test rig and exposed to specific (classical low-frequency, and high-frequency) bearing currents. The induced damages to the surfaces are analysed visually and with the help of an atomic force microscope, and compared for the different electric regimes applied. Further, the electrically damaged bearing surfaces are characterized by standard roughness parameters. The surface structure observable on certain test bearings shows good correlation to the structure found with a bearing that had failed in the field under similar electric conditions. One of the investigated electric regimes applying high-frequency currents proved capable of generating fluting patterns - as found in real applications - on the test rig. The experiments also indicate that high-frequency bearing currents, although in total dissipating less energy, are more dangerous to a bearing than continuous current flow. The presented method gives a good starting point for further investigation on electric current damage in bearings, especially regarding high-frequency bearing currents, and on bearing/grease lifetime under specific electric regimes.

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Hexter, A. T., S. M. Hislop, G. W. Blunn, and A. D. Liddle. "The effect of bearing surface on risk of periprosthetic joint infection in total hip arthroplasty." Bone & Joint Journal 100-B, no. 2 (February 2018): 134–42. http://dx.doi.org/10.1302/0301-620x.100b2.bjj-2017-0575.r1.

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Aims Periprosthetic joint infection (PJI) is a serious complication of total hip arthroplasty (THA). Different bearing surface materials have different surface properties and it has been suggested that the choice of bearing surface may influence the risk of PJI after THA. The objective of this meta-analysis was to compare the rate of PJI between metal-on-polyethylene (MoP), ceramic-on-polyethylene (CoP), and ceramic-on-ceramic (CoC) bearings. Patients and Methods Electronic databases (Medline, Embase, Cochrane library, Web of Science, and Cumulative Index of Nursing and Allied Health Literature) were searched for comparative randomized and observational studies that reported the incidence of PJI for different bearing surfaces. Two investigators independently reviewed studies for eligibility, evaluated risk of bias, and performed data extraction. Meta-analysis was performed using the Mantel–Haenzel method and random-effects model in accordance with methods of the Cochrane group. Results Our search strategy revealed 2272 studies, of which 17 met the inclusion criteria and were analyzed. These comprised 11 randomized controlled trials and six observational studies. The overall quality of included studies was high but the observational studies were at high risk of bias due to inadequate adjustment for confounding factors. The overall cumulative incidence of PJI across all studies was 0.78% (1514/193 378). For each bearing combination, the overall incidence was as follows: MoP 0.85% (1353/158 430); CoP 0.38% (67/17 489); and CoC 0.53% (94/17 459). The meta-analysis showed no significant difference between the three bearing combinations in terms of risk of PJI. Conclusion On the basis of the clinical studies available, there is no evidence that bearing choice influences the risk of PJI. Future research, including basic science studies and large, adequately controlled registry studies, may be helpful in determining whether implant materials play a role in determining the risk of PJI following arthroplasty surgery. Cite this article: Bone Joint J 2018;100-B:134–42.

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Jin, Z. M., D. Dowson, and J. Fisher. "Analysis of fluid film lubrication in artificial hip joint replacements with surfaces of high elastic modulus." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 211, no. 3 (March 1, 1997): 247–56. http://dx.doi.org/10.1243/0954411971534359.

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Lubrication mechanisms and contact mechanics have been analysed for total hip joint replacements made from hard bearing surfaces such as metal-on-metal and ceramic-on-ceramic. A similar analysis for ultra-high molecular weight polyethylene (UHMWPE) against a hard bearing surface has also been carried out and used as a reference. The most important factor influencing the predicted lubricating film thickness has been found to be the radial clearance between the ball and the socket. Full fluid film lubrication may be achieved in these hard/hard bearings provided that the surface finish of the bearing surface and the radial clearance are chosen correctly and maintained. Furthermore, there is a close relation between the predicted contact half width and the predicted lubricating film thickness. Therefore, it is important to analyse the contact mechanics in artificial hip joint replacements. Practical considerations of manufacturing these bearing surfaces have also been discussed.

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Drabu, K. J., R. J. Michaud, P. J. J. McCullagh, K. Brummitt, and R. A. Smith. "Assessment of Titanium Alloy on Polyethylene Bearing Surfaces in Retrieved Uncemented Total Hip Replacements." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 208, no. 2 (June 1994): 91–95. http://dx.doi.org/10.1243/pime_proc_1994_208_270_02.

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Changes to the bearing surfaces of eighteen uncemented total hip replacements retrieved at revision surgery were assessed by three-dimensional binocular microscopy, Rank Taylor Hobson talysurf measurements, scanning electron microscopy, and X-ray dispersive analysis. Abrasions on the non-articular surface of the polyethylene cups were present. Bone particles were found in tracks in the bearing surfaces of both the titanium femoral heads and the polyethylene cups and were responsible for wear of these surfaces. Although the wear of the femoral heads appeared substantial to naked eye examination, the surface finish of these surfaces remained within the British ISO standards for titanium alloy when assessed by the methods used above. This study concluded that direct contact between polyethylene and bone should be avoided in total hip arthroplasty and that ‘third body’ wear from bone particles occurred in these uncemented prostheses. Both components of this type of implant should be replaced at revision surgery and titanium should be avoided as a bearing surface in hip arthroplasty. Present methods of assessing the surface finish of titanium should be re-evaluated and more reliable ones considered.

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Jacobs, Joshua J., and Howard S. An. "Commentary: Total disc arthroplasty and the bearing surface debate." Spine Journal 12, no. 8 (August 2012): 702–4. http://dx.doi.org/10.1016/j.spinee.2011.10.022.

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Sathasivam, Shivani, and Peter S. Walker. "Optimization of the bearing surface geometry of total knees." Journal of Biomechanics 27, no. 3 (March 1994): 255–64. http://dx.doi.org/10.1016/0021-9290(94)90002-7.

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Buechel, Frederick F., Michael J. Pappas, and Louis J. Iorio. "New Jersey Low Contact Stress Total Ankle Replacement: Biomechanical Rationale and Review of 23 Cementless Cases." Foot & Ankle 8, no. 6 (June 1988): 279–90. http://dx.doi.org/10.1177/107110078800800603.

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A congruent contact, unconstrained, multiaxial ankle replacement has been developed for use without cement. A talar onlay component with a trochlear surface and central fixation fin uses a cylindrical articulating axis that reproduces the lateral talar curvature. A tibial inlay component with a 7° anteriorly inclined short fixation stem uses a flat loading plate, recessed anatomically into the distal tibia to distribute tibial loads to the ankle joint. For both components, made of cast cobalt-chromium-molybdenum, a 275-μm pore-size, sintered-bead, porous coating is used to allow tissue ingrowth stabilization. A congruent ultrahigh molecular weight polyethylene bearing is inserted between the metallic implants. Its upper surface is flat, whereas its lower surface conforms to the trochlear surface, thereby providing unconstrained, sliding cylindrical motion with low contact stress on the bearing surfaces. Contact pressure and collateral ligaments maintain ankle stability during both static and dynamic loading conditions. Clinically, 23 total ankle arthroplasties were performed in 21 patients. The follow-up period ranged from 24 months to 64 months with a mean of 35.3 months. Diagnoses included rheumatoid arthritis, 6 patients (26.1%); osteoarthritis, 4 patients (17.4%); post-traumatic arthritis, 10 patients (43.5%); avascular necrosis of the talus, 2 patients (8.7%), and painful ankle fusion, 1 patient (4.3%). Pain was the primary reason for surgery in all cases. Postoperatively, 87% of ankles had no pain or, at most, mild pain. Postoperative complications included poor wound healing in four ankles, reflex sympathetic dystrophy in two ankles, deep infection in one ankle, and one bearing subluxation. No ankle replacements were removed and no fusions were performed for failed implants, although one bearing was exchanged without disrupting the metallic elements. In this report, the suggestion is made that total ankle arthroplasty may have an improved application in various arthritis disorders when used with biologic fixation and unconstrained mobile bearings.

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Zazirnyi, I. M. "Ceramic-on-Ceramic Bearings in Total Joint Arthroplasty. Part 2." Visnyk Ortopedii Travmatologii Protezuvannia, no. 3(114) (December 1, 2022): 49–54. http://dx.doi.org/10.37647/0132-2486-2022-114-3-49-54.

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Summary. Total hip arthroplasty (THA) currently provides durable long-term outcomes, but osteolysis secondary to polyethylene wear debris remains a fundamental cause of aseptic loosening and revision. Conventional polyethylene failed to provide a suitable bearing for young active patients requiring joint replacement because of the significant demands they place on such bearings. Strategies to reduce friction and wear debris lead to the development of ceramic bearings in THA. The next decade is unlikely to see a paradigm shift in the materials used for THA. Instead, the challenges will be dedicated to improve surgical technique in terms of component orientation to improve reproducibility and achieve superior patient outcomes. The optimum bearing surface is one with very low wear rates, a low coefficient of friction, scratch resistance, and is biologically inert. It is also one that can safely accommodate larger femoral head sizes to minimize dislocation rates without damaging the taper junction. Such a material already exists with modern ceramic bearings.

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HEISEL, CHRISTIAN, MAURICIO SILVA, and THOMAS P. SCHMALZRIED. "BEARING SURFACE OPTIONS FOR TOTAL HIP REPLACEMENT IN YOUNG PATIENTS." Journal of Bone and Joint Surgery-American Volume 85, no. 7 (July 2003): 1366–79. http://dx.doi.org/10.2106/00004623-200307000-00026.

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Haidukewych, George J., and Jeffrey Petrie. "Bearing Surface Considerations for Total Hip Arthroplasty in Young Patients." Orthopedic Clinics of North America 43, no. 3 (July 2012): 395–402. http://dx.doi.org/10.1016/j.ocl.2012.05.008.

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Ito, Hiroshi, Akio Minami, Takeo Matsuno, Hiromasa Tanino, Toshio Yuhta, and Ikuya Nishimura. "The sphericity of the bearing surface in total hip arthroplasty." Journal of Arthroplasty 16, no. 8 (December 2001): 1024–29. http://dx.doi.org/10.1054/arth.2001.27673.

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Harris, W. H. "Alternative Bearing Surfaces: Crosslinked Polyethylenes for Total Hip Replacement. A Review." HIP International 13, no. 3 (July 2003): 127–32. http://dx.doi.org/10.1177/112070000301300302.

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Highly crosslinked polyethylene has three major advantages as an alternative bearing surface that are in common with ceramic on ceramic and metal on metal. They are 1) prior long-term in vivo human use, 2) low wear and lysis rates and 3) being a relatively inert material. In addition they have several other advantages not shared by the hard on hard alternatives. They include lower cost, less difficulty from impingement and less difficulty with accelerated wear if the acetabular component is placed in a high degree of abduction. It does not have the brittleness of ceramic nor the metallosis that can accompany the metal on metal bearings. Polyethylene is familiar, without a learning curve. It is more adaptable, with extended lip liners, offset liners and constrained liners. For certain of the crosslinked polyethylenes wear is independent of head diameter. Thus, there appear to be several valuable advantages for considering highly crosslinked polyethylene as the preferred alternative bearing.

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Toh, Shawn Ming Song, Ariyan Ashkanfar, Russell English, and Glynn Rothwell. "Computational method for bearing surface wear prediction in total hip replacements." Journal of the Mechanical Behavior of Biomedical Materials 119 (July 2021): 104507. http://dx.doi.org/10.1016/j.jmbbm.2021.104507.

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Jain, Sanjeev. "“Newer Bearing Surface Total hip arthroplasty in Developmental Dysplasia of hip”." IOSR Journal of Dental and Medical Sciences 8, no. 4 (2013): 01–04. http://dx.doi.org/10.9790/0853-0840104.

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Hachisuka, Kenji, Koichiro Dozono, Hajime Ogata, Saburo Ohmine, Hideo Shitama, and Koichi Shinkoda. "Total surface bearing below-knee prosthesis: Advantages, disadvantages, and clinical implications." Archives of Physical Medicine and Rehabilitation 79, no. 7 (July 1998): 783–89. http://dx.doi.org/10.1016/s0003-9993(98)90356-2.

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Cottrell, Jocelyn M., Elizabeth Townsend, Joseph Lipman, Thomas P. Sculco, and Timothy M. Wright. "Bearing Surface Design Changes Affect Contact Patterns in Total Knee Arthroplasty." Clinical Orthopaedics and Related Research 464 (November 2007): 127–31. http://dx.doi.org/10.1097/blo.0b013e31814d4d46.

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Piconi, Corrado, Vincenzo De Santis, and Giulio Maccauro. "Clinical Outcomes of Ceramicized Ball Heads in Total Hip Replacement Bearings: A Literature Review." Journal of Applied Biomaterials & Functional Materials 15, no. 1 (January 26, 2017): 1–9. http://dx.doi.org/10.5301/jabfm.5000330.

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Background Metallic ball heads for total hip replacement (THR) bearings with ceramicized surfaces were introduced in orthopedics during the second half of the 1980s, with the aim of decreasing the wear of polyethylene cups. Methods An analysis was made of the literature regarding outcomes for metallic ball heads with ceramicized surfaces now in clinical use (TiN, TiNbN, ZrN, monoclinic ZrO2), as well as carbon coatings (pyrolytic carbon, diamond-like carbon) and silicon nitride as coatings in ball heads for THR bearings. Results Notwithstanding the diffusion of ceramicized ball heads in THRs, there are few reports about their clinical outcomes in hip arthroplasty. In addition, several clinical studies and some registry data are putting under scrutiny the clinical advantages of ceramicized ball heads over cobalt chrome (CoCr) alloy and ceramic ball heads. Conclusions The wear of THR bearings with ceramicized ball heads looks like it depends more on the behavior of the polyethylene cups than on the treatment of the ball head surface. The risk of coating damage and of its consequences has to be taken into account in selecting this type of bearing.

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SVIRGUN, Olha, Valentyn SVIRGUN, Roman ANTOSHCHENKOV, and Ivan BRYK. "DETERMINATION OF THE SHAPE OF DEFORMED WORKING SURFACES IN RUBBER-METAL SLIDING BEARINGS." Ukrainian Journal of Applied Economics 6, no. 3 (September 2, 2021): 358–64. http://dx.doi.org/10.36887/2415-8453-2021-3-48.

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In this work, the attempt is made to investigate the deformation types of the bearing surfaces, they have a surface made of a material such as rubber, which is lubricated with water. Rubber bearings are successfully used in cases where the friction unit must be in water or another liquid medium. Along with performing their direct functions, rubber bearings can dampen vibration, noise and some shaft misalignments. The essential feature of bearings with a surface made of materials such as rubber is the unusually low elasticity modulus of the rubber coating, which is tens of thousands of times less than the elasticity modulus of metal surfaces. Water, as a lubricant, also differs from mineral oils in much less dynamic viscosity and has a slightly higher heat capacity and thermal conductivity. The significantly lower ability of water to create thin and strong adsorbed layers on the rubbing surfaces, which depend on the nature of the lubricant, surfaces and the nature of the interaction of oil molecules and a solid. The low dynamic viscosity of water does not allow, under normal operating conditions, hydrodynamic bearings to provide the required minimum thickness of the lubricating layer, which makes it possible to compensate with a margin for possible errors in manufacturing, installation, force and temperature deformations. By the joint solution of the equations of hydrodynamics and equations of the theory of elasticity, taking into account the incompressibility of rubber, certain forms of deformed working surfaces in plain bearings with a working surface made of a material such as rubber were considered. This makes it possible to solve the problems of determining the volumetric deformation of the bearing, assessing the total displacements of the shaft and determining the loads that fall on individual bearing support parts. As a theoretical basis, Newton's second law and the law of conservation of mass are used. Methods of the theory of elasticity are used to assess the deformations of elastic surfaces. When rubber is loaded, there are three types of deformations: elastic, highly elastic and viscous. Under repeated loading, good repeatability of the deformation values is observed. Key words: rubber-metal bearing, water lubrication, forms of deformed working surfaces, theory of elasticity.

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Miyake, Shojiro. "Dust Generation Properties of Solid Lubricant Film Coated and Perfluoropolyether Lubricated Ball Bearings." Journal of Tribology 122, no. 4 (May 8, 2000): 796–802. http://dx.doi.org/10.1115/1.1288929.

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The purpose of this work is to elucidate the properties of ball bearings used for clean applications. Dust, namely wear debris particle generation behavior of ball bearings lubricated with solid lubricant films and low vapor pressure PFPE (perfluoropolyether) grease was investigated using a laser scattering type dust counter under small-angle oscillatory conditions. In the case of the solid lubricated bearing, dust generation began to increase rapidly at a certain number of oscillatory cycles, as deduced from the bearing surface damage. Bearings lubricated with a MoS2/Ag layer and MoS2 sputtered films showed less dust generation, starting torque and surface damage than ion-plated Ag and Au film lubricated and unlubricated bearings. Dust generation was deduced to be due to the damage formation of oscillatory ball bearings, based on the size of the contact elliptic area. The total number of particles generated from the ball bearing lubricated with PFPE grease is very large, but bearing damage is very small. Degraded PFPE was observed on the side plate seal by FTIR. Therefore, dust generation from a PFPE-lubricated bearing is deduced to be due to PFPE degradation. Particles generated from bearings with dry contact include large particles. In contrast, most of the particles generated from bearings lubricated with PFPE grease are very small. Side plate seals of ball bearings decrease the amount of dust generated from these bearings. [S0742-4787(00)00704-9]

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Gholizadeh, Hossein, Noor Azuan Abu Osman, Arezoo Eshraghi, Nooranida Arifin, and Tze Yang Chung. "A comparison of pressure distributions between two types of sockets in a bulbous stump." Prosthetics and Orthotics International 40, no. 4 (January 12, 2015): 509–16. http://dx.doi.org/10.1177/0309364614564022.

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Background:This article describes a total surface bearing prosthetic socket for a patient (25-year-old female) with a bulbous stump.Case Description and Methods:The subject had unstable excessive soft tissue at the distal end of the residuum. After 2 years of prosthetic use, she experienced several problems, including pain in the residual limb and knee joint. Pressure distribution was evaluated during ambulation. We also designed a total surface bearing socket with Velcro as suspension system to distribute the load evenly on the residual limb, and to facilitate donning procedure.Findings and Outcomes:The main site of weight bearing in the old prosthesis (patellar tendon bearing) was anterior proximal region of the residual limb, especially the patellar tendon. The pressure was almost 10 times higher than the distal region during level walking. Pressures were distributed more evenly with the total surface bearing socket design, and the donning was much easier.Conclusion:Pressure distribution within the socket could be affected by socket design and suspension system. Using the total surface bearing socket and Velcro as suspension system might facilitate donning of prosthesis and reduce traction at the end of residual limb during the swing phase of gait.Clinical relevanceProper socket design and suspension system based on the amputees’ need can facilitate rehabilitation process and lead to the amputee’s satisfaction. The pressure is distributed more uniformly over the residual limb by the total surface bearing socket compared to the patellar tendon bearing socket for lower limb amputees with unusual stump shape.

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Peters, Rinne M., Pax Willemse, Paul C. Rijk, Mels Hoogendoorn, and Wierd P. Zijlstra. "Fatal Cobalt Toxicity after a Non-Metal-on-Metal Total Hip Arthroplasty." Case Reports in Orthopedics 2017 (2017): 1–5. http://dx.doi.org/10.1155/2017/9123684.

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This case illustrates the potential for systemic cobalt toxicity in non-metal-on-metal bearings and its potentially devastating consequences. We present a 71-year-old male with grinding sensations in his right hip following ceramic-on-ceramic total hip arthroplasty (THA). After diagnosing a fractured ceramic liner, the hip prosthesis was revised into a metal-on-polyethylene bearing. At one year postoperatively, X-rays and MARS-MRI showed a fixed reversed hybrid THA, with periarticular densities, flattening of the femoral head component, and a pattern of periarticular metal wear debris and pseudotumor formation. Before revision could take place, the patient was admitted with the clinical picture of systemic cobalt toxicity, supported by excessively high serum cobalt and chromium levels, and ultimately died. At autopsy dilated cardiomyopathy as cause of death was hypothesized. A third body wear reaction between ceramic remnants and the metal femoral head very likely led to excessive metal wear, which contributed systemic cobalt toxicity leading to neurotoxicity and heart failure. This case emphasizes that fractured ceramic-on-ceramic bearings should be revised to ceramic-on-ceramic or ceramic-on-polyethylene bearings, but not to metal-on-polyethylene bearings. We aim to increase awareness among orthopedic surgeons for clinical clues for systemic cobalt intoxication, even when there is no metal-on-metal bearing surface.

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Aprato, Alessandro, Giorgio Governale, Alessandro Stucchi, Martino Deregibus, and Alessandro Masse. "Biomaterials in Bearing Surface for Total Hip Arthroplasty: State of the Art." Recent Patents on Biomedical Engineeringe 3, no. 2 (June 1, 2010): 75–85. http://dx.doi.org/10.2174/1874764711003020075.

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Carnes, K. J., S. M. Odum, and J. L. Troyer. "RAPIDLY EVOLVING BEARING SURFACE USE AND COST IN PRIMARY TOTAL HIP ARTHROPLASTY." Value in Health 19, no. 3 (May 2016): A239. http://dx.doi.org/10.1016/j.jval.2016.03.1114.

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Chuang, Wei-Chiao, Hsu-Hao Hsieh, Lai-Hsing Hsu, Hao-Juan Ho, Jo-Tong Chen, and Ming-Ji Tzeng. "A System for Supporting the Design of Total Surface Bearing Transtibial Sockets." Computer-Aided Design and Applications 8, no. 5 (January 2011): 723–34. http://dx.doi.org/10.3722/cadaps.2011.723-734.

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Atwood, S. A., F. E. Kennedy, J. H. Currier, D. W. Van Citters, and J. P. Collier. "In Vitro Study of Backside Wear Mechanisms on Mobile Knee-Bearing Components." Journal of Tribology 128, no. 2 (November 21, 2005): 275–81. http://dx.doi.org/10.1115/1.2162916.

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The long-term success of a total knee replacement depends on the wear performance of a polyethylene bearing that separates a metal femoral component from a metal tibial tray. Although fixed bearing designs secure the polyethylene bearing to the tibial tray, mobile bearing knees allow the polyethylene to move relative to the tibial tray. This study has evaluated the wear performance of an intended articulation on the inferior surface of the LCS®-Rotating Platform mobile bearing by conducting clinically relevant tribological testing and comparing results to retrieved knee bearings. A retrieval analysis leads to the conclusion that third-body particles in the contact produce curvilinear scratches longer than the expected rotation of the knee on both the polyethylene bearing and the CoCr tibial tray. Tribological testing shows that polymethylmethacrylate (PMMA) bone cement particles produce worn surfaces most similar to retrievals. Porous-coating beads and bone debris also have the ability to damage both surfaces. Worn polyethylene surfaces from pin-on-flat tests show scratches longer than the excursion length, and “skipping marks”—pits spaced at smaller rotation intervals along a scratch—as observed in retrievals. These wear features suggest that a ratcheting mechanism, which moves the third-body particles further along the scratch with each cycle, may be responsible for the observed wear.

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Wang, Yan Shuang, Zhe Liu, and Hai Feng Zhu. "Heat Generation of Bearing." Key Engineering Materials 480-481 (June 2011): 962–67. http://dx.doi.org/10.4028/www.scientific.net/kem.480-481.962.

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Heat generation of a bearing was studied based in this paper. Computational models of power loss were built. The total heat generation was gotten. Influences on total heating were analyzed at various inner ring rolling velocities and applied loads. The results show that bearing rolling velocity and axial load affect heat generation strongly. Meanwhile sliding friction, which exists between balls and the cage pocket, cages and the surface of outer ring, is the main factors of bearing heating. Bearings with shaft are mainly used in gyro motors of aviation, aerospace, marine navigational systems, which own a long life and high reliability. Heat generated by friction affects its performance, life and reliability, and consequently influences control precision and life of gyro motors. If the rate of heat dissipation is less than the rate of the heat generation, the system temperatures will raise, the hardness of bearing ring and rolling element steel decrease, and resulting in plastic deformations, lubricant deterioration occurs, ultimately, heat imbalance failure leads to breakage of bearing components and bearing seizure[1,2].So precise evaluating heat generation of bearings with shaft is important for design, manufacture and application of bearing. The heat generation of bearing comes from power loss of friction. The traditional methods contain the local method and integral method [3]. Palmgren who used the integral method based on experimental results advanced an empirical formula of total friction moment [4]. The calculation result is lower than the fact because ignoring infection of lubricant flux. Astringe and Smith improved the above formula .But it was just for roller bearing. Harris established a local method for the ball bearing and rolling bearing [5]. Pouly et al [6, 7] analyzed part power loss of the high speed rolling bearing based on local method. Compared with the integral method, the local method calculated heating of all heat sources. The results were more accurate. Liu Zhi-quan, Han Min-zheng et al computed the heat of high speed rolling and ball bearing by the local method [8, 9]. This paper studies heat generation mechanism of bearing with shaft from a gyro motor. Different heat sources from bearings are calculated by a self-made program. All factors which influence heat generation would be gotten by analyzing at different working conditions. It would offer a theoretical basis for optimal design and proper use of bearings with shaft.

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Martinelli, Nicoló, Silvia Baretta, Alberto Bianchi Castagnone Prati, Francesco Malerba, Carlo Corrado Bonifacini, and Fabio Galbusera. "Contact Stresses in a Fixed-Bearing Total Ankle Replacement." Foot & Ankle Orthopaedics 2, no. 3 (September 1, 2017): 2473011417S0002. http://dx.doi.org/10.1177/2473011417s000284.

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Category: Ankle, Ankle Arthritis, Basic Sciences/Biologics Introduction/Purpose: Third-generation ankle implants with good clinical results continued to increase the popularity of total ankle arthroplasty (TAA) to address end-stage ankle osteoarthritis preserving joint movement. Newer TAA used fixed-bearing designs, with a theoretical increase of contact stresses leading to a higher polyethylene wear. The purpose of this study was to investigate the contact stresses in the polyethylene component of a new third-generation TAA, with a fixed-bearing design, using 3D finite element analysis. Methods: A three-dimensional finite element model was developed based on the Zimmer Trabecular Metal Total Ankle (ZTMTA) and a finite element analysis was employed to evaluate the contact pressure, contact area and Von Mises stress in the polyethylene articular surface in the stance phase of the gait cycle. Results: The peak values were found at the anterior regions of the articulating surface, where reached 19.8 MPa at 40% of gait cycle. The average contact pressure during the stance phase of gait was 6.9 MPa. The maximum von Mises stress of 14.1 MPa in the anterior section was reached at 40% of the gait cycle. For the central section the maximum von Mises stress of 10.8 MPa was reached at 37% of the gait cycle, whereas for posterior section the maximum of 5.4 MPa was reached at the end of the stance phase (60% of the gait cycle). Conclusion: Although, the average von Mises stress was less than 10 MPa, high peak pressure values were recorded. Advanced models to quantitatively estimate the wear are needed to assess polyethylene and metal component survivorship.

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Chang, Jun-Dong, In-Sung Kim, Sameer Ajit Mansukhani, Vishwas Sharma, Sang-Soo Lee, and Je-Hyun Yoo. "Midterm outcome of fourth-generation ceramic-on-ceramic bearing surfaces in revision total hip arthroplasty." Journal of Orthopaedic Surgery 26, no. 2 (May 1, 2018): 230949901878391. http://dx.doi.org/10.1177/2309499018783913.

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Purpose: The purpose of this study is to evaluate the clinical and radiologic outcomes after revision total hip arthroplasty (THA) using fourth-generation ceramic-on-ceramic (CoC) bearing surfaces. Methods: A total of 52 revision THAs (28 men and 19 women) using the fourth-generation CoC bearing surfaces were retrospectively evaluated. Both acetabular cup and femoral stem were revised in all cases. The mean follow-up period was 7.3 years (range, 4.0–9.9 years). The clinical results with Harris hip score (HHS), Western Ontario McMaster Osteoarthritis Index (WOMAC), and radiologic outcomes were evaluated. Results: At the final follow-up examination, the average HHS was 90.4 (range, 67–100). The average WOMAC pain and physical function score were 2.8 (range, 0–12) and 16.4 (range, 0–42), respectively. Complications were observed in 10 hips (19.2%). However, there were no bearing surface-related complications, and no cases of dislocation and squeaking. Retroacetabular pelvic osteolysis without cup loosening was observed in one hip at the final follow-up. However, no hip showed radiographic signs of cup loosening, vertical or horizontal acetabular cup migrations, and changes of inclinations during the follow-up period. Conclusion: Our data showed that clinical and radiologic outcomes after revision THA using fourth-generation CoC bearing were favorable. Hence, revision THA with the use of CoC bearing surfaces can be preferentially considered. Further studies with long-term follow-up data are warranted.

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Chen, Changmin, Jianping Jing, Jiqing Cong, and Chao Ji. "Experimentally study of dynamic pressure distribution and oil film forces in journal bearing using ElectroMechanical Film sensor array." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 234, no. 4 (November 5, 2019): 903–13. http://dx.doi.org/10.1177/0954406219884971.

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The acquisition of the oil film pressure and forces on the bearing pads through experimentation is crucial to understanding the characteristics of journal bearing. Lots of efforts had been taken in film pressure measurement, and the pressure was obtained at specified position on the bearing pads. However, due to the space and structure constraint, merely very limited number of the point pressure can be obtained with traditional sensors and acquiring the detail pressure field on whole bearing pad surface is still an open challenge. In this paper, a method based on thin-film sensors technique is proposed and employed to measure the pressure distribution and oil film forces of journal bearings. The measurement is conducted on a cylindrical journal bearing with two axial grooves, and ElectroMechanical Film sensor arrays are designed and laid on the surface of the bearing pads. The oil film pressure is acquired at up to 32 measurement points in total along the bearing pads in both circumference and axial directions. The pressure distribution in a wide rotation speed range is obtained successfully by using fitting algorithm. Furthermore, the oil film forces on horizon and vertical direction are obtained through the integration of the measured pressure filed. The test results prove that it is feasible to measure the oil pressure filed of journal bearings using ElectroMechanical Film piezo-film sensor array.

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Yiğiter, K., G. Şener, and K. Bayar. "Comparison of the effects of patellar tendon bearing and total surface bearing sockets on prosthetic fitting and rehabilitation." Prosthetics and Orthotics International 26, no. 3 (December 2002): 206–12. http://dx.doi.org/10.1080/03093640208726649.

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Patellar tendon bearing (PTB) and total surface bearing (TSB) sockets have been used respectively in the prosthetic treatment of 20 trans-tibial amputees to investigate the effectiveness of both sockets on prosthetic fitting and rehabilitation. Data analysis showed that prostheses with TSB sockets were lighter than the prostheses with PTB sockets and better suspension was obtained from TSB prosthetic socket (p<0.05). It was also found that weight acceptance on the amputated side advanced to a more normal value with TSB prostheses (p<0.05). There was a statistically significant difference between the two socket types in walking and in other ambulation activities except sitting and standing up from a chair, in favour of the TSB socket (p<0.05). Consequently, due to the outcome of this study it can be said that TSB prosthetic sockets can be used effectively in the rehabilitation of trans-tibial amputees.

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Hesketh, James, Xinming Hu, Duncan Dowson, and Anne Neville. "Tribocorrosion reactions between metal-on-metal and metal-on-polymer surfaces for total hip replacement." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 226, no. 6 (March 29, 2012): 564–74. http://dx.doi.org/10.1177/1350650112442471.

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The open circuit potential and linear polarisation resistance were measured during pin-on-plate tribometer tests for three different total hip replacement bearing material combinations in 0.35% NaCl and bovine serum solutions. In addition, surface analysis was performed using laser interferometry and focused ion beam scanning electron microscopy. It was found that the level of tribologically enhanced corrosion taking place at the bearing surface was substantially higher for metal-on-metal tribocouples than metal-on-polymer ones. Tribological depassivation may be reduced by the presence of organic boundary lubricants.

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Sharplin, Paul, Michael C. Wyatt, Alaistair Rothwell, Chris Frampton, and Gary Hooper. "Which is the best bearing surface for primary total hip replacement? A New Zealand Joint Registry study." HIP International 28, no. 4 (January 12, 2017): 352–62. http://dx.doi.org/10.5301/hipint.5000585.

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Introduction: We have investigated the revision rates of all bearing surface combinations for primary total hip replacement (THR) registered on the New Zealand Joint Registry (NZJR) to determine which coupling has been the most durable and successful over the last 16 years. Methods: There were 106,139 primary THRs registered, resulting in 4,960 revisions for any cause. We examined all-cause revision rates, reasons for revision and performed survival analyses. Results: Ceramic-on-highly cross-linked polyethylene (CoPx) had the lowest all-cause revision rate of 0.54/100-component-years (cys) (95% confidence interval 0.48 to 0.61). This was superior to all other hard-on-soft bearing combinations in unadjusted analysis. Furthermore, the age of patients receiving CoPx was significantly lower than for metal-on-polyethylene (mean 62.9; standard deviation [SD] 10.1 vs. 69.1; SD 9.6; p<0.001). Acetabular loosening was the reason for revision in 14.5% of CoPx, compared to 33% of MoP THRs (p<0.001). Metal-on-metal bearings had the highest revision rate of 1.43/100 cys and were significantly inferior to CoPx (p<0.001). Kaplan-Meier analysis and Cox regression analyses were performed and we adjusted the analyses to control for age, femoral head size, surgical approach and fixation. Conclusions: CoPx remained the most durable and successful coupling used in primary THR in New Zealand irrespective of age, gender or size of femoral head.

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Davis, Edward T., Joseph Pagkalos, and Branko Kopjar. "Effect of Bearing Surface on Survival of Cementless and Hybrid Total Hip Arthroplasty." JBJS Open Access 5, no. 2 (2020): e0075-e0075. http://dx.doi.org/10.2106/jbjs.oa.19.00075.

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TAKANO, Toshiko, Koichiro DOZONO, Kenji HACHISUKA, Tetsuya OKAZAKI, and Hajime OGATA. "Total Surface Bearing Prosthesis for a Below-knee Amputee with the Skin Erosion." Japanese Journal of Rehabilitation Medicine 31, no. 2 (1994): 126–29. http://dx.doi.org/10.2490/jjrm1963.31.126.

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Carnes, K. J., S. M. Odum, J. L. Troyer, and T. K. Fehring. "What Is The Cost-Effective Bearing Surface Choice In Primary Total Hip Arthroplasty." Value in Health 18, no. 3 (May 2015): A161—A162. http://dx.doi.org/10.1016/j.jval.2015.03.936.

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Bills, Paul, Radu Racasan, Saugatta Bhattacharya, Liam Blunt, and Graham Isaac. "Comparative study of material loss at the taper interface in retrieved metal-on-polyethylene and metal-on-metal femoral components from a single manufacturer." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 231, no. 8 (April 8, 2017): 683–90. http://dx.doi.org/10.1177/0954411917701496.

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There have been a number of reports on the occurrence of taper corrosion and/or fretting and some have speculated on a link to the occurrence of adverse local tissue reaction specifically in relation to total hip replacement which have a metal-on-metal bearing. As such a study was carried out to compare the magnitude of material loss at the taper in a series of retrieved femoral heads used in metal-on-polyethylene bearings with that in a series of retrieved heads used in metal-on-metal bearings. A total of 36 metal-on-polyethylene and 21 metal-on-metal femoral components were included in the study all of which were received from a customer complaint database. Furthermore, a total of nine as-manufactured femoral components were included to provide a baseline for characterisation. All taper surfaces were assessed using an established corrosion scoring method and measurements were taken of the female taper surface using a contact profilometry. In the case of metal-on-metal components, the bearing wear was also assessed using coordinate metrology to determine whether or not there was a relationship between bearing and taper material loss in these cases. The study found that in this cohort the median value of metal-on-polyethylene taper loss was 1.25 mm3 with the consequent median value for metal-on-metal taper loss being 1.75 mm3. This study also suggests that manufacturing form can result in an apparent loss of material from the taper surface determined to have a median value of 0.59 mm3. Therefore, it is clear that form variability is a significant confounding factor in the measurement of material loss from the tapers of femoral heads retrieved following revision surgery.

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Li, Junning, Jiafan Xue, and Zhitao Ma. "Study on the Thermal Distribution Characteristics of High-Speed and Light-Load Rolling Bearing Considering Skidding." Applied Sciences 8, no. 9 (September 8, 2018): 1593. http://dx.doi.org/10.3390/app8091593.

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Skidding, which frequently occurs in high-speed rolling bearings, has a significant effect on the thermal distribution and service reliability of the bearings. An improved theoretical model of friction power loss distribution in high-speed and light-load rolling bearings (HSLLRBs) considering skidding is established, and the effects of various operating parameters on the friction power loss are investigated. The results show that the friction power loss of the inner ring and outer ring as well as the total friction power loss of the bearing increase as the slip ratio increases, but that the friction power loss of the cage guide surface and roller oil churning show a reverse trend. In addition, the increase in inner ring speed and kinematic viscosity leads to an increase in bearing friction power loss. The steady and transient temperature field distribution of HSLLRBs is obtained by the finite element method (FEM), and the results show that the inner ring raceway has the highest temperature, whereas the cage has the lowest. The temperature distribution test rig of a full-size roller bearing is constructed, and the influence mechanism of the slip ratio, rotation speed, load, lubrication, and surface topography on the bearing temperature distribution are obtained. The experimental results are consistent with the theoretical results, which also validates the theoretical method.

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Madanat, Rami, Inari Laaksonen, Stephen E. Graves, Michelle Lorimer, Orhun Muratoglu, and Henrik Malchau. "Ceramic bearings for total hip arthroplasty are associated with a reduced risk of revision for infection." HIP International 28, no. 3 (May 2018): 222–26. http://dx.doi.org/10.1177/1120700018776464.

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Introduction: Periprosthetic joint infection (PJI) is a serious complication after total hip arthroplasty (THA) and bearing material’s associations to PJI prevalence is largely unknown. The main purposes of this study were to determine if revision for infection varied depending on the type of bearing surface used in primary THA and to study whether patient or implant related factors had an effect on this variation. Methods: A total of 177,237 primary THA procedures from the Australian Registry (AOANJRR) were analysed. 3 bearing surfaces were compared. Metal-on-highly cross-linked polyethylene (MoXP) bearing had been used in 95,129 hips, ceramic-on-highly cross-linked polyethylene (CoXP) in 24,269 hips, and ceramic-on-ceramic (CoC) in 57,839 hips. Revision rates for infection were compared between the 3 groups. Results: Both MoXP and CoXP had a higher revision rate for infection compared to CoC hips (hazard ratio [HR] 1.46 (1.25, 1.72), p < 0.001) and HR 1.42 (1.15, 1.75), p = 0.001 respectively). Patients aged 70 years or less had a lower revision rate for infection when a CoC bearing was used. This difference was independent of sex, and prostheses selection. No difference was evident if the femoral component was cemented or a head size of 28 mm was used. Discussion: In this registry-based material, use of a CoC bearing was associated with a lower risk of revision for infection in patients younger than 70 years when cementless femoral components were used. Further studies are needed to verify this finding.

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Hintermann, Beat, Lukas Zwicky, Christine Schweizer, Alexej Barg, and Roxa Ruiz. "Axial Rotational Alignment of Mobile-Bearing Total Ankle Arthroplasty." Foot & Ankle Orthopaedics 4, no. 4 (October 1, 2019): 2473011419S0021. http://dx.doi.org/10.1177/2473011419s00216.

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Category: Ankle Arthritis Introduction/Purpose: In total ankle arthroplasty (TAA), component malpositioning is a major cause of implant failure, possibly due to the altered force patterns caused by the malpositioning which are then transmitted to the bone-implant interface or neighboring joints during physiological loading. Mobile-bearing TAA with their second interface, may allow the talus to adapt its position based upon the individual anatomy. However, no data exist on the change in component positioning after implantation. It is unclear whether it is the result of initial positioning during implantation or secondary adjustments such as possible soft tissue adaptions. We aimed to determine the relative axial rotation between the talar and tibial components at the end of surgery and after a minimum of 3 years follow-up. Methods: The relative rotation between the tibial and talar components was measured in two groups. First, intraoperatively before wound closure, in a consecutive series of 58 patients (60 ankles; age 61.8 [31 to 86] years; females 25, males, 35) who underwent TAA between February and November 2018. A K-wire inserted along the medial border of the tibial component and a rectangular marker positioned at the anterior surface of PE insert were used to determine the angle of rotation. Second, in 48 patients (48 ankles; age 60.2 [31 - 82] years; females, 24; males, 24) out of 1411 patients who underwent TAA between January 2003 and December 2015, and in whom a weight-bearing CT scan was taken for evaluation at 6.3 (range, 3.0 -16.3) years. The medial border of the tibial component and a perpendicular line to the anterior surface of the PE insert were used to determine the angle of rotation. Results: The angle of rotation, thus the relative position of the talar component compared to the tibial component, did not differ between the two groups (p = 0.2). While the talus was internally rotated by 1.7 (range, -14.0 - 14.0) degrees at the end of surgery, it was internally rotated by 1.5 (range, -13.0 – 19.5) degrees after a minimum follow-up of 3 years (Figure 1). Conclusion: Although there was no significant difference in average axial position measured intraoperatively compared to a 3- years follow-up, there was a wide range of rotational measurements. The possibility of the talar component to find its position as given by individual anatomy may be crucial in TAA to avoid non-physiological joint loads and shear forces which may otherwise result in increased PE wear. Due to the wide range of measurements, our data suggests that axial talar rotation cannot be predicted preoperatively or intraoperatively by surgical techniques that reference the transtibial axis, tibial tuberosity and transmalleolar axis as guidance for tibial component positioning.

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Galvin, A., L. M. Jennings, H. M. McEwen, and J. Fisher. "The influence of tibial tray design on the wear of fixed-bearing total knee replacements." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 222, no. 8 (November 1, 2008): 1289–93. http://dx.doi.org/10.1243/09544119jeim434.

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Debris-induced osteolysis due to surface wear is a potential long-term problem in total knee replacements (TKRs). Wear between the tibial tray and ultra-high molecular weight polyethylene insert is thought to contribute to the wear. This study investigated the influence of tibial tray design on the wear of fixed-bearing TKRs. Specifically, this study investigated the influence of the material's surface finish and design characteristics of the locking mechanism of the tibial tray on the wear in fixed-bearing knees for both cruciate-retaining (CR) and posterior-stabilized designs. A new fixed-bearing tibial tray design using Co—Cr and with an improved locking mechanism significantly reduced polyethylene wear from 22.8 ± 6.0 mm3 per 106 cycles to 15.9 ± 2.9 mm3 per 106 cycles compared with a previous titanium alloy tray with a CR design. The wear rates were similar to those of a fixed-bearing insert clamped into a tibial tray, suggesting that the decrease in wear was due to a reduction in backside wear. There was no significant difference between the wear rates of a cruciate-retaining design and a posterior-stabilized design under the two kinematic conditions tested.

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Valcarenghi, Jérôme, Nicolas Poinot, Pierre-Bernard Verstraeten, Esfandiar Chahidi, Benoit Caufriez, Vincent Costenoble, and Xavier Collard. "Adverse local tissue reaction after ceramic-on-ceramic total hip arthroplasty." Acta Orthopaedica Belgica 88, no. 1 (March 2022): 43–46. http://dx.doi.org/10.52628/88.1.06.

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We report a rare case of symptomatic adverse local tissue reaction in a patient with a ceramic-on-ceramic total hip bearing surface and review the literature. Probably, ceramic wear debris is not entirely inert and may lead to adverse local tissue reactions.

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Rao, T. V. V. L. N., A. M. A. Rani, M. Awang, and F. M. Hashim. "Stability evaluation of three-layered journal bearing with slip/partial slip." Industrial Lubrication and Tribology 69, no. 3 (May 8, 2017): 334–41. http://dx.doi.org/10.1108/ilt-08-2016-0184.

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Purpose This paper aims to present stability of a three-layered journal bearing considering magnitude of the layers’ thicknesses and viscosities with slip/partial slip on the bearing surface. Design/methodology/approach Modified Reynolds equation based on one-dimensional analysis is derived for a three-layered journal bearing with slip/partial slip. Dynamic coefficients are derived based on infinitesimal perturbation method. Linearized stability analysis is presented taking into account slip/partial slip on bearing surface; thicknesses and viscosities of bearing surface layer; and core layer and journal surface layer. Findings Results of threshold speed and critical whirl frequency ratio coefficients (Cω, CΩ), stiffness (Kij for i = x,y) and damping (Bij for i = x, y) coefficients and threshold speed (ωs) and critical whirl frequency ratio (Ωs) are presented. The bearing surface is analyzed for slip (total surface with slip) and partial slip (partial surface with slip). The slip-on bearing surface reduces stability, while partial slip improves bearing stability. The threshold speed coefficient (Cω) decreases with slip on bearing surface. The threshold speed (ωs) and critical whirl frequency ratio (Ωs) are influenced by the variation of threshold speed coefficient (Cω) and critical whirl frequency ratio coefficient (CΩ), respectively. A three-layered journal bearing with partial slip and thick high viscosity bearing surface layer results in higher threshold speed coefficient and has a potential to improve stability of journal bearing. The analyses indicate that optimal angular extent of partial slip region (θs) enhances the stability of journal bearing. Originality/value The paper presents parametric study of stability coefficients (Cω and CΩ) and evaluation of threshold speed (ωs) and critical whirl frequency ratio (Ωs) of a three-layered journal bearing with slip/partial slip.

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Lau, Yeong J., Shashank Sarmah, and Johan D. Witt. "3rd generation ceramic-on-ceramic cementless total hip arthroplasty: a minimum 10-year follow-up study." HIP International 28, no. 2 (March 2018): 133–38. http://dx.doi.org/10.1177/1120700018768617.

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Introduction: 3rd generation ceramic bearings were introduced in total hip arthroplasty (THA) with the potential to have better mechanical strength and wear properties than their predecessors. At present, there are few studies looking at the long-term results of this latest generation of ceramic bearings. The purpose of our study was to investigate the long-term clinical and radiographic results of 3rd generation ceramic-on-ceramic THA and the incidence of ceramic specific complications such as squeaking and bearing surface fracture. Methods: The database of the senior author (J.D.W.) was reviewed. A total of 126 hip replacements performed in 108 patients (average age 39.6 years) with an average follow-up of 12.1 years (10-16 years) was identified. Clinical notes and plain radiographs were reviewed. To measure function, patients were contacted and an Oxford Hip Questionnaire was completed. Patients were also directly questioned about the presence of squeaking or any other sounds from the hip. Radiographs were evaluated for signs of wear, osteolysis, loosening and heterotopic ossification. The abduction angle of the acetabular component was measured. Results: The average Oxford Hip Score was 39.8 out of 48. Survivorship at 10 years was 94.6% (95% CI) with revision for any cause as the endpoint. There was 1 femoral head fracture, no osteolysis, no squeaking and no detectable wear. Conclusions: The good clinical and radiographic results for this series of patients are similar to other recent long-term studies looking at 3rd generation ceramic-on-ceramic THA. The results compare favourably with other bearing surfaces. The lack of osteolysis associated with this articulation is encouraging and may also make it a good choice for younger patients requiring total hip replacement.

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Journal articles on the topic 'Total surface bearing'

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