Objectives: To find diagnostic points and to identify the origin of osteomyelitis in synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome.
Methods: Fifty-two patients with mandibular suppurative osteomyelitis and 25 patients with mandibular osteomyelitis in SAPHO syndrome were included in the study. Radiographic patterns of the lesion, types of periosteal reaction and the presence of external bone resorption and bone enlargement were investigated in each case and compared between the two entities.
Results: Suppurative osteomyelitis demonstrated an osteolytic pattern and a lamellated type of periosteal reaction, whereas SAPHO syndrome revealed a mixed-pattern, solid-type periosteal reaction, external bone resorption and bone enlargement.
Conclusions: Radiographic examination is suggested to be convenient and a useful diagnostic method of differentiating osteomyelitis in SAPHO syndrome from suppurative osteomyelitis. The periosteum is suspected to be the original site of osteomyelitic lesions in SAPHO syndrome.