Fig. 11

Two examples of incidental bipartite patella. (a) Anteroposterior and (b) tangential patellar radiographs of the right knee in the first example show a patellar fragment at the superolateral aspect of the right patella consistent with bipartite patella. In the second, (c) axial and (d) coronal fat-suppressed proton density MR images of the right knee demonstrate a well-corticated osseous fragment (solid arrow) at the superolateral aspect of the patella. Note the high signal of the synchondrosis (open arrows), the well-preserved underlying cartilage of the patella, and the lack of bone marrow oedema at the adjacent bone that differentiate this variant from a patellar fracture