Solution to Unknown Case #19 – Gibbus Deformity Differential Diagnosis

History: Child with back pain. 

Gibbus Deformity: Lateral radiograph of the lumbar spine reveals a focal kyphosis at the thoracolumbar spine junction (yellow arrow) resulting in sharp angulation at this level, compatible with a Gibbus deformity.

This is the appearance of a Gibbus Deformity. A Gibbus Deformity is a short segment thoracolumbar kyphosis that results in sharp angulation as seen in the image above. The differential diagnosis for a Gibbus deformity is usually divided into congenital and acquired causes, as detailed below:

Congenital Causes of Gibbus Deformity:

1. Achondroplasia
2. Hypothyroidism/Cretinism
3. Mucopolysaccharidoses
4. Apert Syndrome
5. Coffin-Lowry Syndrome

Acquired Causes of Gibbus Deformity:

1. Compression fracture (also called vertebra plana)
2. Eosinophilic granuloma (Langerhans Cell Histiocytosis)
3. Osteomyelitis/discitis (bacterial or tuberculosis)
4. Scheuermann disease