title: Unusual case of mixed form of femoroacetabular impingement combined with nonspecific synovitis of the hip joint in a young adult-- A case report.
abstract: BACKGROUND
  Minimal bone changes in the acetabulum and/or proximal femur, through mechanism known as femoroacetabular impingement, during flexion, adduction and internal rotation lead to early contact between femoral head-neck junction and acetabular brim, in anterosuperior region. Each additional pathological substrate which further decreases specified clearance provokes earlier onset of femoroacetabular impingement symptoms.
  
  
  METHODS
  We presented a 20-year-old male patient with groin pain, limping, positive impingement test, radiological signs of mixed form of femoroacetabular impingement and unrecognized chronic hypertrophic synovitis with earlier development of clinical hip symptoms than it has been expected. Open surgery of the left hip was done. Two years after the surgery, patient was asymptomatic, painless, and free of motion, with stable x-rays.
  
  
  CONCLUSIONS
  Hypertrophic synovial tissue further reduces the distance between the femoral head-neck junction and the acetabulum, leading to the earlier onset of femoroacetabular impingement symptoms. Surgical treatment is the method of choice.
authors.forename: Marko
authors.initials: M
authors.lastname: Mladenović
authors.forename: Ivan
authors.initials: I
authors.lastname: Micić
authors.forename: Zoran
authors.initials: Z
authors.lastname: Andjelković
authors.forename: Desimir
authors.initials: D
authors.lastname: Mladenović
authors.forename: Predrag
authors.initials: P
authors.lastname: Stojiljković
mesh_terms: D001696:Biomechanical Phenomena; D057925:Femoracetabular Impingement / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008297:Male; D011859:Radiography; D020127:Recovery of Function; D013585:Synovitis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult