Intra-articular Focal Nodular Synovitis of the Knee

A 32-year-old woman was referred to physical therapy by her primary care provider (PCP) for complaints of limited right knee extension and pain. Radiographs of her right knee ordered by her PCP prior to physical therapy evaluation were noncontributory. To rule out intra-articular pathology, the physical therapist ordered magnetic resonance imaging, which revealed an intra-articular mass. The radiologist recommended contrast imaging to further characterize the mass, which was found to be consistent with focal nodular synovitis. J Orthop Sports Phys Ther 2017;47(4):293. doi:10.2519/jospt.2017.7221.