Acetabular cause
Middle aged lady with a desire for athletic activity
Causes:
Deep acetabular socket = Coxa profunda (Link to the image) (Another image)
Acetabular retroversion
Protrusio acetabuli
Acetabular rim ossification
Mechanism:Linear contact between acetabular rim and femoral head-neck junction
Femoral head-neck junction to come in contact with acetabular rim
Results in labral degeneration or tear, followed by posteroinferior acetabular chondral injury.
Pathology:Labral damage followed by cartilage damage
Plain radiograph:
Crossover sign - Projection of the acetabular fossa (coxa profunda) or femoral head (protrusio acetabuli) medial to ilioischial line suggets increased acetabular socket depth
Acetabular retroversion - figure of 8 on plain radiograph (normally anterior wall of acetabulum is medial to posterior wall) anterior wall crosses and projects lateral to the posterior wall; medial orientation of ischial spine
(Very good illustration on this blog: Acetabular retroversion)
MR:
Acetabular depth: line connecting anterior and posterior acetabular rims; parallel line through the centre of femoral head; distance between these two lines is acetabular depth. Positive, if the centre of femoral head line is lateral to acetabular rim line.
Management:Reduction of anterior coverage by anteverting periacetabular osteotomy or excision of osseous prominence at acetabular rim
Excision osteoplasty
Reference:
1. FAI
