P. acnes is short for Propionibacterium acnes. It is a type of bacteria that usually lives in the pores of your skin. Most of the time it doesn’t cause any harm but, when the skin is cut during surgery, the bacteria can travel inside and infect parts of the body. The shoulder has a lot of this type of bacteria living there so patients having shoulder operations are prone to this type of infection. Infection with P. acnes is important because it is uncommon and often difficult to diagnose.
Infection with P. acnes after shoulder surgery is RARE and depends on which operation you have had. It occurs, on average, in less than 2% of patients.
P. acnes infection does not show itself like other post-surgical infections. The common infection signs of fever, swelling and redness at the surgical site are not present. Blood tests for infection (CRP and ESR) are often normal.