Diffuse Idiopathic Skeletal Hyperostosis (DISH)¶

Definition¶

Diffuse idiopathic skeletal hyperostosis (DISH), also known as Forestier disease, is a systemic condition characterized by flowing calcification and ossification along the anterolateral aspect of at least four contiguous vertebral bodies with preservation of disc height and absence of facet joint or sacroiliac joint disease.

Diagnostic Criteria (Resnick and Niwayama)¶

All three must be present:

Flowing ossification along the anterolateral aspect of at least 4 contiguous vertebral bodies
Relative preservation of disc height in the affected segments (unlike spondylosis)
Absence of sacroiliac joint erosion, sclerosis, or fusion and absence of apophyseal (facet) joint ankylosis (unlike ankylosing spondylitis)

Epidemiology¶

Prevalence: ~10–25% of adults over 50
Male predominance (2:1)
Associated with metabolic syndrome: diabetes, obesity, dyslipidemia
Most common in the thoracic spine (right side predominant — the left side is relatively protected by aortic pulsation)

Imaging Findings¶

Radiography/CT¶

Flowing anterolateral ossification spanning ≥4 contiguous vertebral bodies — the hallmark
"Dripping candle wax" or "flowing" morphology — distinct from marginal osteophytes
Ossification is typically separated from the anterior vertebral body by a radiolucent line (distinguishing it from osteophytes which arise directly from the body margin)
Disc heights are preserved — unlike degenerative spondylosis
Right thoracic predominance (left side spared by aortic pulsation)
Peripheral enthesopathy: calcaneal spurs, olecranon spurs, patellar tendon ossification

MRI¶

Thickened, low-signal band along the anterior vertebral bodies on sagittal T1 and T2
Preserved disc hydration (unlike DDD)
No facet joint or SI joint inflammation

Differential Diagnosis¶

Feature	DISH	Ankylosing Spondylitis	Spondylosis
Ossification	Flowing, anterolateral, ≥4 levels	Syndesmophytes (thin, vertical, marginal)	Osteophytes (horizontal, from body margin)
Disc height	Preserved	May be preserved early	Decreased
SI joints	Normal	Bilateral sacroiliitis (hallmark)	Normal
Facet joints	Normal	May ankylose	Degenerative
Age/Sex	>50, male	20–40, male	>50, either

Clinical Pearl

Patients with DISH have a rigid, ankylosed spine that is vulnerable to fractures from even minor trauma — similar to ankylosing spondylitis. DISH fractures are often unstable (they behave like long bone fractures) and may be missed on initial imaging because the fracture line can be subtle within the ossified ligament. CT is essential for fracture detection in DISH patients with new-onset back pain after trauma. An unstable DISH fracture with epidural hematoma is a surgical emergency.

Key Points¶

DISH = flowing anterolateral ossification of ≥4 contiguous levels with preserved disc height and normal SI/facet joints
"Dripping candle wax" morphology on lateral radiographs
Right thoracic predominance (left protected by aortic pulsation)
Associated with metabolic syndrome (diabetes, obesity)
Distinguishable from ankylosing spondylitis by normal SI joints and from spondylosis by preserved disc height
DISH spine is fracture-prone — even minor trauma can cause unstable fractures

References¶

Mader R, Baraliakos X, Eshed I, et al. Imaging of diffuse idiopathic skeletal hyperostosis (DISH). RMD Open. 2020;6(1):e001151. https://pmc.ncbi.nlm.nih.gov/articles/PMC7046956/
Kuperus JS, Oudkerk SF, Foppen W, et al. Criteria for Early-Phase Diffuse Idiopathic Skeletal Hyperostosis: Development and Validation. Radiology. 2019;291(2):420–426. https://pmc.ncbi.nlm.nih.gov/articles/PMC6493062/
Oudkerk SF, de Jong PA, Attrach M, et al. Diagnosis of diffuse idiopathic skeletal hyperostosis with chest computed tomography: inter-observer agreement. European Radiology. 2017;27(1):188–194. https://pmc.ncbi.nlm.nih.gov/articles/PMC5127853/
Eshed I. Imaging Characteristics of Diffuse Idiopathic Skeletal Hyperostosis: More Than Just Spinal Bony Bridges. Diagnostics (Basel). 2023;13(3):563. https://pmc.ncbi.nlm.nih.gov/articles/PMC9914876/
Luo TD, Varacallo MA. Diffuse Idiopathic Skeletal Hyperostosis. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK538204/
Diffuse idiopathic skeletal hyperostosis. Radiopaedia. https://radiopaedia.org/articles/diffuse-idiopathic-skeletal-hyperostosis