title: Spontaneous recurrent hemarthrosis of the knee in the elderly: arthroscopic treatment and etiology.
abstract: OBJECTIVE
  To elucidate the etiology of and find a preferable surgical treatment for spontaneous recurrent hemarthrosis in osteoarthritic knee joints arthroscopically.
  
  
  METHODS
  Nineteen patients referred to our institution from affiliate hospitals between April 1998 and October 2006 were involved in this study. Their demographics, preoperative radiographic findings, preoperative magnetic resonance imaging (MRI) findings, arthroscopic findings and procedures performed, the patient's medical history, and the postoperative clinical course were retrospectively reviewed.
  
  
  RESULTS
  There were 9 male and 10 female patients with average age of 61.9 years (range, 41 to 83 yrs). The average number of joint aspirations before surgery was 5.4. The average time from onset to arthroscopy was 10 months. Radiographs showed 2 knees with isolated lateral compartment osteoarthritis (OA), one with isolated patellofemoral (PF) OA, 14 with medial and lateral compartment OA, and 2 with tricompartmental OA. Classifying them according to the dominant compartment, 6 knees were medial-dominant OA, 11 lateral-dominant OA, and 2 PF-dominant OA. The MRI scans revealed 18 grade III lateral menisci and 1 grade II lateral menisci. Even with 6 medial-dominant OAs, lateral meniscal involvement was more obvious than medial meniscal involvement on MRI. Subtotal lateral meniscectomy accompanied with coagulation of the bleeding points was performed on 17 cases. For 2 PF OA cases, synovectomy and a histologic examination of synovium were performed. Remission was obtained for 18 cases. The unsuccessful case had cirrhosis of the liver.
  
  
  CONCLUSIONS
  A majority of the patients (17 of 19) had degenerative torn lateral menisci confirmed with MRI and at arthroscopy. Successful outcomes were achieved by meniscectomy and coagulation. Most so-called spontaneous recurrent hemarthroses in OA knee joints appear to be attributable to torn lateral menisci.
  
  
  METHODS
  Level IV, therapeutic case series.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan. sasho@faculty.chiba-u.jp
authors.forename: Takahisa
authors.initials: T
authors.lastname: Sasho
authors.forename: Shuhei
authors.initials: S
authors.lastname: Ogino
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tsuruoka
authors.forename: Koichi
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Nobuyasu
authors.initials: N
authors.lastname: Ochiai
authors.forename: Ryota
authors.initials: R
authors.lastname: Nagashima
authors.forename: Hideshige
authors.initials: H
authors.lastname: Moriya
authors.forename: Atsuya
authors.initials: A
authors.lastname: Watanabe
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Wada
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Takahashi