The Crucial Role of Lubrication in Joint Replacement Design

Joint replacement surgeries have revolutionized the field of orthopedics, providing relief and improved mobility to many patients suffering from joint diseases such as osteoarthritis and rheumatoid arthritis. Nowadays, due to an aging population and a desire for an active lifestyle, the number of these operations has considerably increased [1, 2]. Studies indicated that wear and debris are the main problems leading to the failure of joint implants, and lubrication can considerably decline these acute complications [3, 4]. It is noticeable that the existence of lubrication is evident in healthy synovial joints such as the hip and knee joints, where it relies on the presence of synovial fluid (Figure 1).  Thus, I firmly believe that lubrication is crucial in designing joint replacements because it ensures the durability and functionality of joint implants while reducing complications and patient pain. To end this, the main purpose of my PhD project is to design a hip prosthesis that can replicate the natural lubrication found in synovial joints.

Figure 1) Anatomy of a healthy a) hip joint b) knee joint [5]
The significance of lubrication in joint replacement design is explained in detail as follows. One of the main functions of lubrication in joint prostheses is to reduce friction between the different components. As these joint replacements imitate the motion of the natural joints, they experience numerous mechanical stresses daily. Inadequate lubrication can lead to generating friction between the bearing surfaces and accelerating wear which can result in premature implant failure. The lubrication film functions as a protective barrier, avoiding direct contact between the bearing surfaces and thereby minimizing friction and wear. Furthermore, complications of friction between different components of the prostheses include implant loosening, osteolysis, and debris discharged into the joint space. These issues may cause discomfort, instability, and eventually implant failure as well as revision surgery. Effective lubrication prevents these issues by declining friction and wear, which in turn significantly increases the lifespan of joint replacements. Additionally, lubrication is crucial not only for the mechanical performance of the implant but also for the patient’s comfort and functionality. Appropriate lubrication reduces the feeling of joint stiffness and soreness to a great extent, significantly restores joint function, and allows patients to have a more active life post-surgery. Enhanced patients’ quality of life is a contributing factor in the success of joint replacements.

In conclusion, the significance of lubrication in orthopedic implant design cannot be overstated. It can noticeably contribute to the accomplishment of life-altering joint replacement surgeries as lubrication substantially enhances the durability and functionality of prostheses by decreasing friction, minimizing complications, and increasing patient comfort.

References

[1] A. Ford, Z. Hua, S. J. Ferguson, L. A. Pruitt, and L. Gao, “A 3D-transient elastohydrodynamic lubrication hip implant model to compare ultra high molecular weight polyethylene with more compliant polycarbonate polyurethane acetabular cups,” Journal of the Mechanical Behavior of Biomedical Materials, vol. 119, p. 104472, 2021.

[2] L. Wang, G. Isaac, R. Wilcox, A. Jones, and J. Thompson, “Finite element analysis of polyethylene wear in total hip replacement: A literature review,” Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, vol. 233, no. 11, pp. 1067-1088, 2019.

[3] L. Mattei, F. Di Puccio, B. Piccigallo, and E. Ciulli, “Lubrication and wear modelling of artificial hip joints: A review,” Tribology International, vol. 44, no. 5, pp. 532-549, 2011.

[4] L. Gao, X. Lu, X. Zhang, Q. Meng, and Z. Jin, “Lubrication Modelling of Artificial Joint Replacements: Current Status and Future Challenges,” Lubricants, vol. 10, no. 10, p. 238, 2022.

[5] https://childrenswi.org/medical-care/rheumatology/conditions/anatomy-of-a-joint

 

This article was written by Mahdieh Mosayebias part of an ongoing series of scientific communications written and curated by BioTrib’s Early Stage Researchers.

Mahdieh is researching the Design of Self Lubricating Prothesis at ETH Zurich, Switzerland.