Which cervical levels are indicated by the wink sign in rheumatoid arthritis?

• A. C3-C4
• B. C1-C2
• C. C2-C3
• D. C4-C5

Answer: (B)

The upper cervical spine, especially the joint between the first and second vertebrae (C1–C2), is a common target in rheumatoid arthritis because synovitis and ligamentous laxity there can lead to instability. The wink sign is a radiographic clue of this instability at C1–C2, typically reflecting rotatory or translational misalignment between the atlas and axis due to destruction of stabilizing structures like the transverse ligament. On imaging, this instability can give the appearance of an asymmetric or “wink-like” alignment at the C1–C2 level, and it’s most evident on dynamic views that show how C1 moves relative to C2. Recognizing this sign is important because instability at C1–C2 can threaten the spinal cord or brainstem, even when symptoms are mild. While rheumatoid disease can affect other cervical levels as well, the wink sign specifically points to abnormalities at the C1–C2 junction.