Factors affecting the outcome of septic arthritis of the shoulder joint with arthroscopic management

Good results have been reported with arthroscopic therapy of septic arthritis of the shoulder; however, few studies have focused on the risk factors for failure of arthroscopic surgery. The purpose of this study was to identify the risk factors affecting the recurrence or death post-surgery in cases of septic arthritis of the shoulder. We retrospectively assessed the records of patients who underwent surgical treatment for septic arthritis of the shoulder between 2009 and 2019. Patients were divided into 2 groups based on complete recovery, recurrence, or death after a single arthroscopic surgery: the eradicated group and the recurred/death group. To identify risk factors for the failure of arthroscopic surgery for septic arthritis of the shoulder, the following parameters were considered: age, sex, presentation of a rotator cuff tear, the arthroscopic staging of the infection, diabetes mellitus, the causative organism, preoperative white blood cell count, and C-reactive protein level in blood. We compared two groups with respect to the presence of potential risk factors. This study included 22 patients with a mean age of 67.9 years. Septic arthritis of the shoulder was eradicated completely with a single arthroscopic surgery in 17 patients (77.3%). However, failure of the surgery resulting in recurrence or death was observed in 5 patients (22.7%). No significant differences were observed in other parameters between the two groups except for the causative organism. Methicillin-resistant Staphylococcus aureus was found in 1 patient (5.9%) in the eradicated group. On the other hand, Methicillin-resistant S. aureus was found in 3 patients (60%) in the recurred/death group (p = 0.024). Most patients with septic arthritis of the shoulder are effectively treated with a single arthroscopic surgery. This study suggests that Methicillin-resistant S. aureus as the causative organism may be the most important prognostic factor in these cases.