In the sports community, we know a lot about the knee injury caused by an ACL tear but much less about the problems caused by patellar dislocations.  This is due to patellar dislocation being less common than ACL tears and also because there is much more variability in the anatomy supporting structures that stabilize the patella. Listen in to Andrew Cosgarea, an orthopaedic surgeon specializing in sports medicine and professor of orthopaedic surgery, as he shares the ongoing studies of patellar instability at Johns Hopkins Medicine.