Management of deep postoperative shoulder infections: is there a role for open biopsy during staged treatment?

BackgroundDespite the gold standard treatment of 2-stage exchange arthroplasty, reinfection after periprosthetic shoulder infections and periarticular osteomyelitis can be as high as 37%. This study describes a protocol to detect persistent deep shoulder infection before revision arthroplasty.MethodsPatients who presented with periprosthetic shoulder infections and osteomyelitis after previous surgery were treated with a standardized protocol of irrigation and debridement (I&D), removal of implants, antibiotic cement spacer placement, and pathogen-directed antibiotic therapy for 6 weeks. After completion of antibiotics and resolution of clinical symptoms, specimens were obtained from an open biopsy performed in the operating room, followed by revision arthroplasty at a later date if final cultures were without evidence of infection. If evidence of infection persisted, then another course of I&D and antibiotic treatment was performed. American Shoulder and Elbow Surgeon scores were used to evaluate clinical outcomes.ResultsEighteen patients were included between 2005 and 2012. The most common pathogens isolated were Propionibacterium acnes (44%), Staphylococcus epidermidis (39%), and S aureus (22%). Four patients (22%) had evidence of persistent infection on specimens from open biopsy and required subsequent rounds of I&D before replantation. The infecting pathogen in 75% of patients with persistent infection was P acnes, and 38% of patients with P acnes infection had recurrence. Mean follow-up of 24 months showed no signs of recurrent infection in any patient and an average American Shoulder and Elbow Surgeon score of 71.ConclusionDespite prior staged treatment for deep postoperative shoulder infections, specimens obtained from open biopsy before replantation detected a persistent infection rate of 22% in all patients and 38% in patients with P acnes infection, which may indicate a role for this procedure in the prevention of recurrent infections.