Eosinophilic Granuloma¶

Definition¶

Eosinophilic granuloma (EG) is the most common and most benign form of Langerhans cell histiocytosis (LCH), a disorder characterized by clonal proliferation of Langerhans cells. In the spine, EG classically produces the vertebra plana — a uniformly flattened vertebral body — most commonly in children and young adults.

Imaging Findings¶

Radiography and CT¶

Vertebra plana — The classic finding: a vertebral body that is uniformly compressed to a thin wafer of bone, with preservation of the adjacent disc spaces and intact posterior elements
Lytic lesion within the vertebral body, which may precede collapse
No significant soft tissue mass (helps distinguish from malignancy)
May also present as a focal lytic lesion in the posterior elements

MRI¶

Uniformly compressed vertebral body with low T1 and high T2/STIR signal
Surrounding soft tissue edema may be present but no significant epidural mass
Enhancement is variable
Adjacent disc spaces are preserved

Clinical Pearl

The differential diagnosis for vertebra plana in a child includes eosinophilic granuloma (most common), Ewing sarcoma, leukemia/lymphoma, and infection. EG is the most likely diagnosis if the child has a solitary flattened vertebra with preserved disc spaces, no significant soft tissue mass, and no systemic symptoms. In adults, metastatic disease and myeloma are more common causes.

Clinical Features¶

Most common in children aged 5–15 years
Back pain, often with local tenderness
May present with mild kyphosis
Self-limiting in many cases — the vertebral body may partially reconstitute height over time

Management¶

Observation — Many cases resolve spontaneously with partial or complete vertebral body height restoration
Bracing — For symptomatic relief and prevention of progressive collapse
Biopsy — When the diagnosis is uncertain or to exclude other causes of vertebra plana
Low-dose radiation or intralesional corticosteroid injection — For refractory or multifocal disease

Key Points¶

Vertebra plana in a child is eosinophilic granuloma until proven otherwise
Disc spaces are preserved and there is no significant soft tissue mass
Partial reconstitution of vertebral body height can occur over time
Biopsy is indicated when the diagnosis is uncertain
Most cases are self-limiting

References¶

Jha SK, Killeen RB, De Jesus O. Eosinophilic Granuloma. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; updated 2025 Jan 22. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559038/
Huang WD, Yang XH, Wu ZP, Huang Q, et al. Langerhans cell histiocytosis of spine: a comparative study of clinical, imaging features, and diagnosis in children, adolescents, and adults. Spine J. 2013;13(9):1108-17. Available from: https://pubmed.ncbi.nlm.nih.gov/23602327/
Baky F, Milbrandt TA, Arndt C, Houdek MT, Larson AN. Vertebra Plana in Children May Result from Etiologies Other Than Eosinophilic Granuloma. Clin Orthop Relat Res. 2020;478(10):2367-2374. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC7491903/
Villas C, Martínez-Peric R, Barrios RH, Beguiristain JL. Eosinophilic granuloma of the spine with and without vertebra plana: long-term follow-up of six cases. J Spinal Disord. 1993;6(3):260-8. Available from: https://pubmed.ncbi.nlm.nih.gov/8347979/
Langerhans cell histiocytosis (skeletal manifestations). Radiopaedia. Available from: https://radiopaedia.org/articles/langerhans-cell-histiocytosis-skeletal-manifestations-1
Langerhans Cell Histiocytosis. Pediatric Imaging. Available from: https://pediatricimaging.org/diseases/langerhans-cell-histiocytosis/
Zaveri J, La Q, Yarmish G, Neuman J. More than Just Langerhans Cell Histiocytosis: A Radiologic Review of Histiocytic Disorders. RadioGraphics. 2014;34(7):2008-2024. Available from: https://pubs.rsna.org/doi/abs/10.1148/rg.347130132