Arthroscopic debridement for septic arthritis of the shoulder joint: post-infectious arthritis is an inevitable consequence?

PURPOSE: The purpose of this study was to compare clinical outcomes and development of post-infectious arthritis of the shoulder joint after single (Group S) or repeated (Group R) arthroscopic debridement surgeries. We hypothesized that (1) repeated surgeries might be attributable to initial subchondral involvement resulting from septic arthritis and (2) the repeated surgery group would exhibit a higher incidence of post-infectious arthritic changes and inferior clinical outcomes due to prolonged resolution of the infection. METHODS: This study included 42 patients (single surgery, n = 29; repeated surgery, n = 13) who underwent arthroscopic debridement for septic arthritis and had a minimum of 2 years of postoperative follow-up data. All patients underwent preoperative magnetic resonance imaging (MRI) with gadolinium enhancement to evaluate subchondral bone involvement suspicious for osteomyelitis secondary to septic arthritis and extension of infection around the glenohumeral joint. Functional and radiological outcomes were assessed. RESULTS: Group S experienced a shorter duration (25.4 days) of infection than Group R (39.7 days) (p = 0.002). Increased signal intensity in the subchondral bone on preoperative MRI was identified in 9 patients (31%) in Group S and 5 patients (38%) in Group R. Post-infectious arthritic changes developed in 6 (21%) and 5 (38%) in Groups S and R, respectively. However, there were no significant differences between groups. At the final follow-up, there were no significant differences in functional assessments. CONCLUSION: Despite a prolonged period of infection in the repeated surgery group, there was no significant difference in development of post-infectious arthritic changes or clinical outcomes in patients requiring single or repeated surgeries. LEVEL OF EVIDENCE: Retrospective comparative study, III.