title: Functional and radiographic outcomes of unstable juvenile osteochondritis dissecans of the knee treated with lesion fixation using bioabsorbable pins.
abstract: BACKGROUND
  The purpose of this study was to evaluate the functional and radiographic outcome of fixation of unstable juvenile osteochondritis dissecans lesions of the knee after a minimum of 2 years of follow-up.
  
  
  METHODS
  A total of 33 unstable juvenile osteochondritis dissecans lesions in 30 patients underwent fixation using bioabsorbable pins through arthrotomy or under arthroscopy. The patients consisted of 23 males and 7 females, and the average age at the time of operation was 14.4 years (range, 11 to 17 y). The functional outcomes were evaluated using the Lysholm score and Hughston's criteria at a mean follow-up of 3.3 years (range, 2.1 to 6.3 y). Healing of the osteochondritis dissecans lesions were confirmed by plain radiographs and magnetic resonance imaging.
  
  
  RESULTS
  The Lysholm score improved significantly at 3 months after the surgery, and was maintained until the final follow-up. Radiographically, 32 of 33 lesions healed after fixation of the lesion (healing rate was 97.0%). Healing was achieved at an average of 2.4 months on plain radiographs and 4.2 months on magnetic resonance imaging. According to Hughston's criteria, 25 patients were graded as excellent, 4 as good, and 1 as poor at the final follow-up.
  
  
  CONCLUSIONS
  The fixation of the unstable juvenile osteochondritis dissecans lesions with bioabsorbable pins demonstrated improved clinical outcomes and radiographic high healing rates at a mean of 3.3 years of follow-up. We advocate this procedure for patients with unstable juvenile osteochondritis dissecans lesions of sufficient quality to enable fixation which will preserve the normal contour of the distal femur.
  
  
  METHODS
  Level IV-retrospective case series.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Adachi
authors.forename: Masataka
authors.initials: M
authors.lastname: Deie
authors.forename: Atsuo
authors.initials: A
authors.lastname: Nakamae
authors.forename: Atsushi
authors.initials: A
authors.lastname: Okuhara
authors.forename: Goki
authors.initials: G
authors.lastname: Kamei
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Ochi
mesh_terms: D020341:Absorbable Implants; D000293:Adolescent; D001178:Arthroplasty / Q000379:methods*; D001182:Arthroscopy / Q000379:methods*; D001858:Bone Nails; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D010008:Osteochondritis Dissecans / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D017063:Outcome Assessment, Health Care; D011859:Radiography; D020127:Recovery of Function; D012189:Retrospective Studies