Factors affecting the occurrence of osseous lesions in septic shoulder arthritis and the recurrence rate after arthroscopic surgery

Abstract

Hypothesis: The purpose of this study was to determine the incidence of osseous lesions and the recurrence rate after arthroscopic surgery in shoulder septic arthritis patients and evaluate the influencing factors.

Materials and methods: We retrospectively reviewed 44 patients who underwent arthroscopic surgery for septic arthritis of the shoulder between January 2012 and September 2019. The average age of the patients was 65.57 ± 14.2 years, and 56.8% were female patients. The minimum follow-up period was 12 months (average, 32.8 ± 14.2 months; range, 12-72 months). We assessed variables including sex, age, underlying diseases, duration from symptom onset to magnetic resonance imaging (MRI), duration from symptom onset to surgery, radiologic results (radiography and MRI), history of injection therapy, and postoperative infection. The incidence of osseous lesions and the recurrence rate were calculated according to independent variables. In addition, multivariate logistic regression was performed to identify the risk factors for osseous lesions and recurrent infection after adjustment for other variables.

Results: Twenty-one patients had an osseous lesion on MRI, and 12 patients had evidence of bone erosion on radiographs. In univariate analyses, significant (P < .05) risk factors for the presence of osseous lesions were female sex, lower C-reactive protein level, and longer duration from symptom onset to MRI. The overall infection recurrence rate was 22.7% (10 of 44 patients). Culture results and the duration from symptom onset to surgery were significant risk factors for recurrent infection (P < .05). As the duration from symptom onset to MRI increased by 1 day, the probability of osseous lesions increased 1.31-fold (95% confidence interval, 1.08- to 1.59-fold; P = .007), and this probability was significantly higher after correction for other risk factors.

Conclusions: To reduce the severity of septic shoulder infection, timely diagnosis and treatment are essential. Even if osseous lesions are present, good results can be obtained if meticulous débridement is performed through arthroscopic surgery. However, functional and radiologic long-term follow-up studies are needed in patients with osseous lesions.

Keywords: Shoulder; arthroscopic surgery; osseous lesion; recurrence; risk factor; septic arthritis.