A preformed antibiotic-loaded spacer for treatment for septic arthritis of the shoulder.

Background: Total shoulder arthroplasty infections are rare, depending on the use of antibiotic prophylaxis, the local blood supply, the axial load gradient and the proximal location of the shoulder. The purpose of this study was to evaluate the results of treatment for infections in total shoulder arthroplasty and septic arthritis using a preformed antibiotic-loaded spacer. Materials and methods: Seven shoulders in as many patients were treated for infected arthroplasty or septic arthritis without previous surgery. A preformed antibiotic-loaded spacer was always applied. Patients were evaluated at the final follow-up with the Constant Score (CS), the Secec Elbow Score (SES), and the American Shoulder and Elbow Society Score (ASESS). Results: The mean follow-up was 40, 71 months after spacer implant. Infection was always confirmed preoperatively by the leukocyte and neutrophil counts in the aspirated synovial fluid, and intra-operative biopsy and pathologic analysis. Positive bacterial cultures were found in 5 cases: 3 MRSA and 2 Staphylococcus epidermidis. The mean SES increased from 34.43 before spacer implant to 77.29 at final follow-up, ASESS ranged from 14.86 to 21.14, and CS from 40.28 to 79.14. Conclusion: A preformed antibiotic-loaded spacer is intended to release gentamicin alone, but we can consider adding vancomycin to increase antibiotic spectrum. An early diagnosis and an immediate treatment can prevent a persistent infection and severe soft-tissue damage. The use of a preformed antibiotic spacer allows maintaining joint function at the intermediate stage in two-stage treatment.