Table 1.

Study Exclusion Criteria^a

Exclusion Criteria
Previous surgery for patellar dislocation
Previous major traumas of the knee joint (ligament ruptures, intra-articular fractures, etc)
MRI not performed in study hospitals
Loose fragment containing only cartilage or bone
Extra-articular medial patellofemoral ligament avulsion fractures
Chondral or osteochondral impression fractures with no loose fragment
Round-shaped OCF fragment interpreted as an old fracture (ie, did not occur in the most recent dislocation)

^aMRI, magnetic resonance imaging; OCF, osteochondral fracture.