Abstract
Double-layered patella (DLP) is a rare form of bipartite patella, pathognomonic for a certain type of chondrodysplasia, named multiple epiphyseal dysplasia (MED). This patellar deformity may be asymptomatic, but it may also cause several complaints, including anterior knee pain and severe maltracking of the patella. We present the case of a young man with recurrent anterior knee pain, mainly provoked by movement, who was already known to have MED.