Trochlear dysplasia in an 18 year old boy

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

Trochleoplasty was done to reshape the trochlea
After removing subchondral bone from 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