📌 Why the Anterior Tubercle Looks Hypertrophied.

https://youtube.com/shorts/lNWo2j3_COw

 

Accessory articulation of the cervical transverse process is a rare congenital anatomical variant caused by elongation of the anterior tubercle (costal element), forming a pseudoarthrosis with the adjacent vertebra.

Most commonly reported at C5–C6; C6–C7 is exceptionally rare.

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Key Imaging Concept

At levels with accessory articulation, the transverse process—particularly the anterior wall of the foramen transversarium—may show chronic stress–related bony remodeling due to long-standing abnormal biomechanical load.

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CT: The Decisive Modality

CT with multiplanar (especially sagittal oblique) reformats reveals:

• Elongated anterior tubercle forming a joint-like articulation
• Smooth, corticated margins
• Uniform, well-defined articulation gap
• Secondary osseous hypertrophy, inconsistent with acute trauma
• No displacement or adjacent soft tissue injury

This secondary hypertrophy strongly supports a non-fracture etiology.

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Fracture vs. Accessory Articulation

Accessory articulation

• Rounded, developmental morphology
• Smooth cortical continuity
• Uniform joint-like space
• Possible contralateral minor anomaly
• No soft tissue swelling
• No marrow edema on MRI

 

Acute fracture

• Sharp, irregular fracture line
• Fragment separation or displacement
• Trauma-consistent morphology
• Soft tissue swelling or hematoma
• Bone marrow edema

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Take-Home Message

If an “anterior tubercle fracture” looks too smooth and symmetric,
consider accessory articulation before calling fracture or tumor.

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#CervicalSpine, #Radiology, #MSKRadiology, #CTPitfall, #FractureMimic, #SpineImaging, #CongenitalVariant, #Neuroradiology, #CervicalCT, #AccessoryArticulation, #Vibecase

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