Here's an online explanation
@Sunnyhippy
Any infection in your body can spread to your joint replacement.
Infections are caused by bacteria. Although bacteria are abundant in out gastrointestinal tract and
on our skin, they are usually kept in check by our immune system. For example, if bacteria make it into
our bloodstream, our immune system rapidly responds and kills the invading bacteria.
However, because joint replacements are made of metal and plastic, it is difficult for the immune system to attack bacteria that make it to these implants. If bacteria gain access to the implants, they may multiply and cause an infection.
Despite antibiotics and preventive treatments, patient with infected joint replacements often require surgery to cure the infection.
The most common ways bacteria enter the body include:
Through breaks or cuts in the skin
During major dental procedures (such as tooth extraction or root canal)
Through wounds from other surgical procedures.
Hope this helps you have a better understanding.