title: SAPHO Syndrome: Imaging Findings of Vertebral Involvement.
abstract: Imaging findings in patients with a combination of synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) are often misinterpreted as discitis/osteomyelitis or metastases, resulting in multiple biopsies and delayed diagnosis. We have incidentally noted a semicircular morphology in vertebral body imaging in several cases of SAPHO syndrome with vertebral involvement. Our goal was to evaluate the prevalence of this distinctive morphology in these patients.
  
  
  
  A retrospective review of patients with SAPHO syndrome diagnosed between July 1998 and August 2013 was conducted. A descriptive analysis of MR imaging, CT, radiography, bone scanning, and PET imaging was performed for the presence and distribution of vertebral body signal intensity or attenuation changes and/or enhancement; contiguous vertebral body involvement; vertebral body collapse; endplate irregularity; disc space, facet, and spinous process involvement; subligamentous thickening; and paraspinal soft-tissue involvement.
  
  
  
  Eighteen patients (16 women [89%]; mean age, 52.9 years) with SAPHO and spine involvement were included. Contiguous involvement of ≥2 vertebral bodies was found in 16 patients (89%), with a curvilinear or "semicircular" pattern involving portions of adjacent vertebral bodies in 10 (63%, P = .14). Most intervertebral discs demonstrated absence of abnormal T2 hyperintensity (73%) and enhancement (89%). Subligamentous thickening was present in 12 (67%). Paraspinal soft-tissue involvement was present in 6 (33%).
  
  
  
  SAPHO syndrome should be included in the differential diagnosis in a patient with a curvilinear or semicircular pattern of vertebral involvement, contiguous vertebral body involvement, and absence of intervertebral disc edema and enhancement.
authors.affiliation: From the Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: A M
authors.identifier: 0000-0001-7164-4127
authors.initials: AM
authors.lastname: McGauvran
authors.affiliation: From the Department of Radiology, Mayo Clinic, Rochester, Minnesota. Kotsenas.amy@mayo.edu.
authors.forename: A L
authors.identifier: 0000-0003-0463-955X
authors.initials: AL
authors.lastname: Kotsenas
authors.affiliation: From the Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: F E
authors.identifier: 0000-0001-9458-8017
authors.initials: FE
authors.lastname: Diehn
authors.affiliation: From the Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: J T
authors.identifier: 0000-0001-5187-2333
authors.initials: JT
authors.lastname: Wald
authors.affiliation: From the Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: C M
authors.identifier: 0000-0002-4585-2958
authors.initials: CM
authors.lastname: Carr
authors.affiliation: From the Department of Radiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: J M
authors.identifier: 0000-0001-5035-3910
authors.initials: JM
authors.lastname: Morris
mesh_terms: D020083:Acquired Hyperostosis Syndrome / Q000000981:diagnostic imaging* / Q000473:pathology; D000328:Adult; D003937:Diagnosis, Differential; D015299:Discitis / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010019:Osteomyelitis / Q000175:diagnosis / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D055815:Young Adult