Prosthetic joints
Prosthetic joints have improved the quality of life for many people, but they come with a small but serious risk of infections from biofilms.
Medical devices can be classified into different groups. Most implants are prosthetics, (Tande and Patel, 2014) man-made body parts that are used to replace original body parts if they are damaged or missing. These synthetic materials can restore the function of the original bone, organ or limb. For example, when somebody cannot move their knee, doctors can replace it with an artificial knee (like a robot) so that they can walk again. But sometimes bacteria can contaminate the prosthetic and cause infections.
Implantation of prosthetic joints has improved the quality of life for many people suffering with joint disease or injury. However, the development of infection, which usually happens during surgery, can cause serious infections (Arciola et al., 2018; Ribeiro et al. 2012) and represents a major complication. The bacteria, Staphylococcus aureus and Staphylococcus epidermidis, account for the majority of prosthetic joint infections.
This is one of the most challenging problems in orthopaedics. Usually, removing the prosthesis is needed as antibiotics cannot efficiently kill bacteria infecting a joint. Advances in diagnostics and management of these infections are urgently needed.
Two-thirds of medical device-associated infections are caused by Staphylococcus species, mostly Staphylococcus aureus and coagulase-negative staphylococci (CoNS) (Ribeiro et al. 2012). Staphylococcus aureus and S. epidermidis account for almost 65% of prosthetic joint infections (Percival et al., 2015). Infections caused by Staphylococcus aureus (also known as MRSA) bacteria are the worst because it is resistant to the antibiotic methicillin.
Further reading on biofilms and prosthetic joints
Arciola, C. R., Campoccia, D. and Montanaro, L. (2018) ‘Implant infections: adhesion, biofilm formation and immune evasion’, Nature Reviews Microbiology, vol. 16, pp. 397-409, https://doi.org/10.1038/s41579-018-0019-y.
Percival, S.L., Suleman, L., Vuotto, C. and Donelli, G. (2015) ‘Healthcare-associated infections, medical devices and biofilms: risk, tolerance and control’, Journal of Medical Microbiology, vol. 64(4), pp. 323-34, https://doi.org/10.1099/jmm.0.000032.
Ribeiro, M., Monterio, F. J. and Ferraz, M. P. (2012) ‘Infection of orthopedic implants with emphasis on bacterial adhesion process and techniques used in studying bacterial-material interactions’, Biomatter, vol. 2(4), pp. 176-94, https://doi.org/10.4161/biom.22905.
Tande, A. J. and Patel, R. (2014) ‘Prosthetic Joint Infection’, Clinical Microbiology Reviews, vol. 27(2), pp. 302-345, https://doi.org/10.1128/CMR.00111-13.