title: Direct comparison of different surgical approaches in a woman with bilateral osteochondrosis dissecans of her knees: a case report.
abstract: BACKGROUND
  Osteochondrosis dissecans is a disorder of the subchondral bone potentially affecting the adjacent articular cartilage. There remains disunity with regard to treatment methods.
  
  
  METHODS
  We present the case of a 21-year-old Swiss woman who presented with clinically symptomatic bilateral osteochondrosis dissecans lesions at both medial femoral condyles. She underwent sequential surgical intervention and was prospectively monitored using clinical scores and magnetic resonance imaging. Her left knee was treated with an open refixation of the osteochondrosis dissecans lesion with two 2.0 mm screws in combination with a cancellous bone graft and subchondral drilling since the cartilage of the osteochondrosis dissecans lesion was intact. On her right knee, she underwent open removal of the defective bone and cartilage, cancellous bone graft with subchondral drilling and coverage with a bilayered collagenous membrane (autologous matrix-induced chondrogenesis technique) since the cartilage of the osteochondrosis dissecans lesion was not intact. At final follow-up 12 months after surgery her Lysholm score had improved from 79 to 95 on her left side and from 74 to 78 on her right. Magnetic resonance imaging displayed good integration of the cancellous bone graft with a slight irregularity at the articular surface on her left side (magnetic resonance observation of cartilage repair tissue (MOCART) 75). The magnetic resonance imaging of her right knee depicted satisfying bony reconstitution with yet more irregularity at the joint surface (magnetic resonance observation of cartilage repair tissue 65) in comparison to her left femoral condyle.
  
  
  CONCLUSIONS
  In cases of failed conservative treatment of osteochondrosis dissecans lesions of the knee joint surgery should be taken into consideration. Considering this case, we believe that the focus should be the preservation of the cartilaginous layer whenever possible or at least replacement with high quality replacement tissue, such as autologous chondrocyte implantation.
authors.affiliation: Schulthess Clinic, Musculoskeletal Centre, Lengghalde 2, CH-8008, Zurich, Switzerland. marco.schneider@orthopia.com.
authors.forename: Marco M
authors.initials: MM
authors.lastname: Schneider
authors.affiliation: Schulthess Clinic, Musculoskeletal Centre, Lengghalde 2, CH-8008, Zurich, Switzerland. stefan.preiss@kws.ch.
authors.forename: Stefan
authors.initials: S
authors.lastname: Preiss
authors.affiliation: Schulthess Clinic, Musculoskeletal Centre, Lengghalde 2, CH-8008, Zurich, Switzerland. gian.salzmann@kws.ch.
authors.forename: Gian M
authors.initials: GM
authors.lastname: Salzmann
mesh_terms: D000328:Adult; D016025:Bone Transplantation; D002358:Cartilage, Articular / Q000473:pathology*; D005260:Female; D005269:Femur / Q000637:transplantation*; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D010008:Osteochondritis Dissecans / Q000000981:diagnostic imaging / Q000534:rehabilitation / Q000601:surgery*; D010012:Osteogenesis; D011859:Radiography; D000068958:Return to Sport; D013997:Time Factors; D014182:Transplantation, Autologous; D016896:Treatment Outcome; D016474:Weight-Bearing