title: Solitary synovial chondromatosis as a cause of Hoffa's fat pad impingement.
abstract: BACKGROUND
  Synovial chondromatosis is a benign disease of synovial membrane usually affecting knee, elbow and shoulder joints. It rarely appears as a solitary formation and exceptionally within Hoffa's fat pad.
  
  
  METHODS
  We report a case of solitary synovial chondromatosis within Hoffa's fat pad as a cause of its impingement in a female patient aged 63. At first, the patient had anterior knee pain with limited extension of the knee. Standard radiogram showed only mild patellofemoral osteoarthritic changes. Magnetic resonance of the knee showed ovoid solitary formation within Hoffa's fat pad repressing its superior part between the kneecap and distal femur. Histopathological examination confirmed a case of extra-articular synovial chondromatosis. The tumorous mass was extracted surgically en bloc.
  
  
  CONCLUSIONS
  Solitary synovial chondromatosis is an uncommon cause of Hoffa's fat pad impingement and anterior knee pain in elderly female patients and can easily be misinterpreted as a different diagnosis.
authors.forename: Mirsad
authors.initials: M
authors.lastname: Maljanovič
authors.forename: Vladimir
authors.initials: V
authors.lastname: Ristič
authors.forename: Predrag
authors.initials: P
authors.lastname: Rasovič
authors.forename: Radmila
authors.initials: R
authors.lastname: Matijevič
authors.forename: Vukadin
authors.initials: V
authors.lastname: Milankov
mesh_terms: D000273:Adipose Tissue / Q000473:pathology* / Q000601:surgery; D015838:Chondromatosis, Synovial / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008875:Middle Aged