Septic arthritis

A joint is the site of articlation of two or more bones in the body, it allows mobility and function, whilst being stable at the same time and allowing weight bearing, an example of this is the knee joint or the hip joint. Septic arthritis is an infection involving one of the joints in the body, most commonly infection involves only one joint, but it can affect more than one joint simultaneously.  All native joints and prosthetic joints are at risk of infection.

What is it caused by?

Most cases of septic arthritis in humans are caused by a bacteria called staphylococcus aureus. This bacteria is normally found on human skin (is is part of the normal bacteria found on human skin and is therefor termed comensal bacteria). It may entre the body through a break in the integrity of the skin (such as cuts or scratches). Septic arthritis can also be caused by other types of bacteria, viruses, or fungal organisms. The very old, very young, or those with suppression of the immune system or certain disease (such as diabetes) are at greater risk of infections in general.

How does it present?

Infections anywhere in the body generally make the patient unwell, often they are associated with temperatures. Locally the infected part is painful and swollen, and thus impedes function (for example an infected knee will make it difficult to walk). In severe infections the patients may become unstable and require hospitalisation.

It is important to diagnose and treat septic arthritis early, to avoid local damage to the joint from these infections, and harmful effects to the patient in general.

Many cases of septic arthritis require urgent surgery. Surgery aims to remove fluid build-up in the affected joint and lavage the joint, and relevant medications (ie antibiotics for the specific bacteria). Further surgery may be required to wash out infected joints, or to replace prosthetic components, Dr Ihsheish can discuss your case individually with you, it is important to be aware that the treatment with antibiotics is for several weeks at least.

Not all infected joints make the patient severely unwell, some low grade infections will be relatively mild in presentation, but if you have any concerns you are advised to make an apointment as soon as possible.