title: Predictive factors for osteochondritis dissecans of the lateral femoral condyle concurrent with a discoid lateral meniscus.
abstract: OBJECTIVE
  Osteochondritis dissecans (OCD) of the lateral femoral condyle is relatively rare, and it is often reported in combination with discoid lateral meniscus. However, little is known about the mechanism underlying this connection. Predictive factors for OCD coinciding with discoid lateral meniscus in Japanese children and adolescents were assessed.
  
  
  METHODS
  During 2000-2015, 152 knees in 133 patients aged 5-15 years were diagnosed with symptomatic complete discoid lateral meniscus. Patients were evaluated using radiography and magnetic resonance imaging (MRI). OCD was radiographically graded using the Brückl classification. Based on Ahn's MRI classifications, discoid lateral meniscus was divided into four types of meniscal shift: no shift (N), anterocentral (AC), posterocentral (PC), or central (C). Relationships between OCD and patient sex, age and Ahn's shift type were analysed.
  
  
  RESULTS
  OCD of the lateral femoral condyle was associated with discoid lateral meniscus in 22 (14.5%) of 152 knees. OCD was classified as Brückl's stage 1 in 5 knees, stage 2 in 12, stage 3 in 3, stage 4 in 1, and stage 5 in 1. OCD was found in 12 of 96 knees (12.5%) with type N meniscal shift, 4 of 24 knees (16.7%) with type AC, 0 of 21 knees (0%) with type PC, and 6 of 11 knees (54.5%) with type C. Multivariate logistic regression analysis showed that males had a significantly increased odds ratio (OR) [14.8; 95% confidence interval (CI) 2.6-83.4]. Those aged 5-11 years had a significantly higher OR (12.5; 95% CI 2.8-55.9) than those aged 12-15 years. The OR for type C coinciding with OCD was significantly elevated (13.4; 95% CI 2.3-78.7).
  
  
  CONCLUSIONS
  Concurrent OCD was found in 22 (14.5%) of 152 knees with discoid lateral meniscus. Male sex, young age (5-11 years), and having a type C meniscal shift of the discoid lateral meniscus as shown by MRI were found to be predictive factors for OCD of the LFC.
  
  
  METHODS
  III.
authors.affiliation: Department of Orthopaedic Surgery, Shimada Hospital, 100-1 Kashiyama, Habikino, Osaka, 583-0875, Japan.
authors.forename: Junsei
authors.initials: J
authors.lastname: Takigami
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan. hussy@med.osaka-cu.ac.jp.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hashimoto
authors.affiliation: Department of Orthopaedic Surgery, Shimada Hospital, 100-1 Kashiyama, Habikino, Osaka, 583-0875, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Tomihara
authors.affiliation: Department of Orthopaedic Surgery, Osaka City General Hospital, 2-13-22 Miyakojima-hondori, Miyakojima-ku, Osaka, 534-0021, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Yamasaki
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Tamai
authors.affiliation: Department of Public Health, Osaka City University Faculty of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Kondo
authors.affiliation: Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Nakamura
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007564:Japan; D007592:Joint Diseases / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008592:Menisci, Tibial / Q000000981:diagnostic imaging / Q000473:pathology; D010008:Osteochondritis Dissecans / Q000175:diagnosis / Q000209:etiology*; D011859:Radiography; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Ahn classification; Brückl classification; Discoid lateral meniscus; Magnetic resonance imaging (MRI); Osteochondritis dissecans (OCD); Radiography