Complications of antibiotic cement spacers used for shoulder infections

Background Our aim was to evaluate complications related to commercially available antibiotic cement spacers used in the treatment of shoulder infections. Methods We performed a retrospective review of commercially available antibiotic spacers implanted in 53 patients (60 spacers) between April 2009 and October 2017 as part of a 2-stage treatment plan for infection at the site of a shoulder arthroplasty (n = 39), other (non-arthroplasty) shoulder surgery (n = 8), or primary shoulder infection without previous surgery (n = 6). All patients were followed up from spacer placement to second-stage revision to shoulder arthroplasty. Ten patients retained the spacers and were followed up for a minimum of 1 year. Results No complications were associated with implantation of the spacers. Of the 44 patients (50 spacers) who underwent a second-stage revision after a mean interval of 6 months (range, 2-18 months), 14 patients had 18 complications. Fourteen complications occurred between implantation and removal. The most common complication was bone erosion (6 in the glenoid and 2 in the humeral shaft). Other complications were fractures of the spacer (n = 4), spacer rotation (n = 3), and humeral fracture (n = 3). Two complications required reoperation. There were 4 spacer-related complications among the 10 patients who retained the implant (3 erosions of the humeral shaft and 1 humeral shaft fracture); none required reoperation or removal. Conclusions Complications related to antibiotic spacers are common especially between the first and second stage of revision, and awareness of these complications is important for the treating provider.