A 50-year-old man presented with acute neck pain and limited range of motion. Axial (Figure A) and sagittal (Figure B) images from contrast-enhanced CT demonstrate an amorphous calcification in the prevertebral soft tissues at the level of the odontoid process (yellow arrows). A fusiform fluid collection measuring < 30 Hounsfield units smoothly enlarges the retropharyngeal space (red arrows) without rim enhancement or enhancing nodular component.
Calcific tendinitis of the longus colli muscle (also known as retropharyngeal tendinitis), is an acute inflammatory response to calcium hydroxyapatite crystal deposition in the longus colli muscle tendons.1 Almost all patients present with neck pain and nearly half have swelling, limited range of motion, and odynophagia. Other frequent clinical findings may include low-grade fever and mildly elevated inflammatory markers.1,2
CT is the gold standard for diagnosis as it is most sensitive for detecting calcifications associated with this inflammatory process. These calcifications are typically within the prevertebral space at the C1-C2 level but can occur anywhere between C1-T3. Identifying calcification within this classic location is an important diagnostic feature to distinguish it from a potentially life-threatening retropharyngeal abscess, which presents as a rim-enhancing fluid collection, suppurative retropharyngeal adenopathy, and mass effect. The differential diagnosis also includes trauma, tumor, disc herniation, and epidural abscess.
Calcific tendinitis of the longus colli muscle is a self-limited process that resolves in 1 to 2 weeks and is treated conservatively with supportive care, NSAIDS, and corticosteroids.1,2 No follow-up imaging is necessary.
Shiang T, Cerniglia C. JAOCR at the Viewbox: Calcific Tendinitis of the Longus Colli Muscle. J Am Osteopath Coll Radiol. 2020;9(2):28.