Propionibacterium acnes infection following shoulder arthroscopy

Authors: Emma Torrance & Lennard Funk

Background:
Proprionibacterium acnes (P.acnes) has recently emerged as a chronic infection following shoulder surgery.  Patients with P.acnes infection often present with persistent, unexplained shoulder pain with a limited range of movement.  A number of studies have recently investigated the incidence of P.acnes post-operatively but have focused primarily on shoulder arthroplasty. we aim to evaluate the presence of P.acnes infection following arthroscopic shoulder surgery.

Materials and Methods:
Intraoperative tissue samples were collected from 12 patients with suspected P.acnes infection over a thirteen month period.  The patient cohort had a mean age of 46.58±19.14, consisting of 50% males.  

Results:
Of the 12 patients who had suspected P.acnes infection following arthroscopic shoulder surgery, 50% were positive (n=6). The mean age was 46.16±18.22, consisting of 83.33% males. The index surgical procedures included rotator cuff repair (n=4) and stabilisation (n=2) resulting in an incidence of 3.7% and 2.7% of all respective procedures.  Interestingly, 40% of positive cultures were first surgical cases of the day. Cultures took a mean 12.57 days to grow in enriched media.  A marked reduction in pain and regained range of movement was demonstrated in 83.33% of patient (n=5) following a 6 week treatment of P.acnes-sensitive antibiotics.

 Conclusion:
Proprionibacterium acnes should be considered as possible cause of unexplained persistent shoulder pain and stiffness following arthroscopic shoulder surgery. Particularly in males, first case of the day and rotator cuff repairs. P acnes should be considered in cases with ongoing pain and stiffness after surgery that does not respond to the usual treatments.