positive carpal sign

The positive carpal sign is a useful radiographic sign for the diagnosis of Turner syndrome in association with the other musculoskeletal manifestations.

Radiographic features

Abnormality in the shape of the proximal carpal row in the dorsopalmar radiographs of the wrist and hand (taking in the neutral position is key to the sign).

In order to obtain more precise data, two tangent lines must be drawn, the first touching the proximal contour of scaphoid and lunate bones and the second touching the triquetral and lunate bones. The intersection of these tangents resulted in an angle called the carpal angle.

When there is an abnormal angular shape of the proximal carpal row and the carpal angle is 117° or less; this is called the positive carpal sign .

Differential diagnosis

Although positive carpal sign may be seen in 5.4% of normal population, the incidence of this sign in gonadal dysgenesis (e.g. Turner syndrome) was about 10 times as high as in normal subjects .

Siehe auch:

• Turner-Syndrom
• gonadal dysgenesis