Intra-articular nodular fasciitis of the knee in a 4-year-old girl: a case report and review of the literatureKo, Po Y.a; Huang, Ming T.a; Song, Hsiang L.b; Lin, Mark C.-J.aJournal of Pediatric Orthopaedics B: July 2013 - Volume 22 - Issue 4 - p 350–352 doi: 10.1097/BPB.0b013e328356379f Femur & Knee Abstract Author Information Nodular fasciitis is a benign, proliferative lesion of myofibroblasts developed from the fascia. It arises commonly in the upper extremities of adults and in the head and neck region of infants and children. Involvement of the knee is exceedingly rare. We report a case of a 4-year-old girl with a knee mass, causing limitation of knee flexion and pain. Arthroscopic examination was performed followed by arthrotomy and tumor excision. Pathologic findings revealed clusters of spindle cells with arrangement of storiform pattern in a loosely textured mucoid matrix. To the best of our knowledge, this is the youngest patient associated with articular nodular fasciitis in the knee joint. Departments of aOrthopaedics bPathology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan Correspondence to Mark C.-J. Lin, MD, Department of Orthopedics, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, No.138, Shengli Rd., Tainan 704, Taiwan Tel: +886 6 234 6519; fax: +886 6 276 6189; e-mail: email@example.com © 2013 by Lippincott Williams & Wilkins, Inc.