Case report: bipartite tibial epiphysis: radiologic and arthroscopic presentation.

We report the case of a bilateral bipartite ossification center of the proximal tibia in a 15-year-old boy with a history of knee injury. The presence of the duplicated ossific centers was an incidental finding on radiography and computed tomography performed after injury. Arthroscopy showed continuous hyaline cartilage between the two ossific centers confirming the diagnosis of a developmental abnormality; however, the articular surface was depressed in the region overlying the smaller ossific center. We presume the presence of an accessory center in the posteromedial aspect of the tibial plate could be a source of instability for the corresponding capsular and meniscal structures. This is, to our knowledge, the first report of tibial bipartite epiphysis.