This 27 year-old female patient suffered spinal injuries and bilateral posterior hip dislocation in a motorcycle accident while riding at high speed hitting an open car door. Axial CT image of the right hip (click image for arrows) demonstrates a fracture of the anterior articular surface of the femoral head (black arrow), a fracture of the posterior margin of the acetabulum (green arrow), and a fragment of bone (grey arrow) in the soft tissues posterior to the acetabulum, which had arisen from the posterosuperior femoral head (not shown).
Note the inguinal hernia repair fixateurs anterior to the pubic bone.
The combination of anterior femoral head cortical fracture and posterior acetabular rim fracture is commonly seen in posterior dislocations of the hip, and is analogous to the Hill-Sachs and bony Bankart lesions seen in shoulder dislocation.
Reference: Richardson P, Young JWR, Porter D. CT Detection of Cortical Fracture of the Femoral Head Associated with Posterior Hip Dislocation. AJR 155:93-94, July 1990
Credit: Dr Laughlin Dawes
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