18 year old engineering student presented with recurrent patellar dislocation and pain.
O/E
positive apprehension test. tuber sulcus angle of 10 degrees
xray- crossing sign and trochlear bump present
MRI showed a convex trochlea
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Trochleoplasty was done to reshape the trochlea
After removing subchondral bone from
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the trochlea from proximal to disatal direction and collapsing the cartilage to ereshape the trochlea.
the final ic at 6 weeks during Chondron implantation for the patella