Abstract: Objective: To explore the ultrasonographic features of the anterior chest wall（ACW）in patients with SAPHO syndrome. Methods: he ultrasonic examination data of patients with SAPHO syndrome confirmed from 2021 to 2025 and with anterior chest wall involvement were retrospectively analyzed. Results: A total of 110 patients were included in this study. The lesions of the anterior chest wall showed an asymmetric distribution, mainly involving the sternoclavicular joint, sternocostal joint and manubrium sterni region. Sternoclavicular arthritis was detected in 55 patients, and 30 patients had sternocostal joint involvement. The distribution of bone erosion showed the following characteristics: the sternum was the most common involved site (75 cases, 68.1%), followed by rib bone involvement (43 cases, 39.1%) and clavicle bone destruction (39 cases, 35.6%). In addition, 42 patients (38.2%) were accompanied by imaging findings such as adjacent soft tissue thickening or echo changes. Conclusion: The anterior chest wall lesions of SAPHO syndrome are characterized by synovitis, bone erosion and soft tissue swelling, which provide an important basis for its early diagnosis and condition assessment.

Key words: SAPHO syndrome, ultrasound, anterior chest wall, synovitis, bone erosion