Two-stage arthroplasty for the treatment of chronic osteomyelitis after routine arthroscopic knee surgery

Corynebacterium pseudodiphtheriticum is a normal inhabitant of the upper respiratory tract and is rarely thought of as a true pathogen. Although this microorganism has been associated with respiratory complications, a few case reports have demonstrated its ability to cause orthopedic infections. A recent review of the literature was performed regarding this specific bacteria and its association with bone and joint infection. To the author's knowledge, the current case is the first reported case of chronic osteomyelitis from Corynebacterium pseudodiphtheriticum after arthroscopic knee surgery. Isolation of this bacterial species on routine microbial cultures has been proven to be challenging in prior studies. In the current case, difficulty isolating this bacterial species on routine cultures led to a significant delay in diagnosis, which ultimately resulted in end-stage joint destruction. Treatment of the infection was accomplished using a 2-stage total knee arthroplasty technique, with the initial placement of an articulated, antibiotic-loaded spacer followed by a subsequent conversion to total knee arthroplasty. This case serves as a useful reminder that clinically subtle infections can occur after minor orthopedic surgery. Surgeons must remain vigilant to render a timely diagnosis and avoid severe sequelae that can result from an undetected pathogen after arthroscopic surgery.