title: Factors associated with meniscal body extrusion on knee MRI in overweight and obese women.
abstract: To determine factors associated with higher degree of meniscal body extrusion in overweight and obese women at high risk of knee osteoarthritis (OA).
  
  
  
  We used baseline data of the PRevention of knee Osteoarthritis in Overweight Females (PROOF) study, Netherlands, comprising overweight or obese women aged 50-60 years, free of clinical knee OA. All subjects completed a questionnaire on knee complaints and physical activity, underwent physical examination, radiography, and 1.5 T magnetic resonance imaging (MRI) of both knees. Using the mid-coronal MRI slice, one blinded observer measured tibial plateau width and meniscal body extrusion of both menisci in both knees. The association between baseline factors and meniscal extrusion, were analyzed with a random effects regression model. In addition, we used a fixed effect regression model for evaluation of knee-specific factors.
  
  
  
  Mean age of the included women (n = 395) was 55.7 years and mean body mass index (BMI) 32.4 kg/m2. Of all knees, 23% had an absolute medial meniscus body extrusion ≥3.0 mm and 4% had lateral meniscus body extrusion ≥3.0 mm. In the multivariable model, the medial meniscus extrusion was increased by 0.44 mm (95% confidence interval [CI] 0.11, 0.77) when a medial meniscus tear was present, by 0.20 mm per 5 kg/m2(95% CI 0.05, 0.35) increase in BMI and by 0.25 in the presence of mild knee symptoms (95% CI 0.05 to 0.44). Kellgren-Lawrence (KL) grade ≥1 and tibia width were associated with increased both medial and lateral extrusion.
  
  
  
  In women, ipsilateral meniscus tear and high BMI are factors associated with medial meniscus body extrusion.
authors.affiliation: Lund University, Faculty of Medicine, Department of Clinical Sciences Lund, Orthopaedics, Clinical Epidemiology Unit, Lund, Sweden. Electronic address: fan.zhang@med.lu.se.
authors.forename: F
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Department of Orthopaedics, Erasmus MC, University Medical Center Rotterdam, The Netherlands; Department of General Practice, Erasmus MC, University Medical Center Rotterdam, The Netherlands. Electronic address: s.bierma-zeinstra@erasmusmc.nl.
authors.forename: S M
authors.initials: SM
authors.lastname: Bierma-Zeinstra
authors.affiliation: Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, The Netherlands. Electronic address: e.oei@erasmusmc.nl.
authors.forename: E H G
authors.initials: EHG
authors.lastname: Oei
authors.affiliation: Lund University, Faculty of Medicine, Department of Clinical Sciences Lund, Orthopaedics, Clinical Epidemiology Unit, Lund, Sweden. Electronic address: aleksandra.turkiewicz@med.lu.se.
authors.forename: A
authors.initials: A
authors.lastname: Turkiewicz
authors.affiliation: Lund University, Faculty of Medicine, Department of Clinical Sciences Lund, Orthopaedics, Clinical Epidemiology Unit, Lund, Sweden; Clinical Epidemiology Research & Training Unit, Boston University School of Medicine, Boston, MA, USA. Electronic address: martin.englund@med.lu.se.
authors.forename: M
authors.initials: M
authors.lastname: Englund
authors.affiliation: Department of General Practice, Erasmus MC, University Medical Center Rotterdam, The Netherlands. Electronic address: j.runhaar@erasmusmc.nl.
authors.forename: J
authors.initials: J
authors.lastname: Runhaar
mesh_terms: D000046:Academic Medical Centers; D017677:Age Distribution; D000368:Aged; D000704:Analysis of Variance; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D016208:Databases, Factual; D005260:Female; D006801:Humans; D015994:Incidence; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008592:Menisci, Tibial / Q000000981:diagnostic imaging / Q000473:pathology; D008875:Middle Aged; D009426:Netherlands; D009765:Obesity / Q000150:complications / Q000453:epidemiology; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000503:physiopathology; D050177:Overweight / Q000150:complications / Q000453:epidemiology; D011379:Prognosis; D012307:Risk Factors; D017678:Sex Distribution; D000070600:Tibial Meniscus Injuries / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology
keywords: Knee; Magnetic resonance imaging; Meniscus; Osteoarthritis; Women