On an AP pelvis radiograph of an adolescent with suspected slipped capital femoral epiphysis, a line drawn along the superior border of the femoral neck (Klein's line) fails to intersect any part of the capital epiphysis. What is this finding called?

• A Capener's sign
• B Southwick's angle abnormality
• C Steel's metaphyseal blanch sign
• D Trethowan's sign ✓

Explanation

Normally Klein's line crosses the lateral portion of the capital epiphysis. When the epiphysis slips posteriorly and medially, it no longer intersects the line, leaving the epiphysis entirely above it; this is Trethowan's sign. Steel's metaphyseal blanch sign refers to the double density of the displaced epiphysis superimposed on the metaphysis on AP views. Capener's sign describes loss of density in the metaphysis adjacent to the physis.

Reference: Mercer's Textbook of Orthopaedics and Trauma, 13th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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