title: Spinal epidural lipomatosis: a common imaging feature in Scheuermann disease.
abstract: METHODS
  Retrospective study.
  
  
  OBJECTIVE
  To find out if spinal epidural lipomatosis (SEL) occurs more commonly among patients with Scheuermann disease than in the general population.
  
  
  BACKGROUND
  On the basis of our own radiologic and operative observation, SEL seems to occur frequently in patients with Scheuermann disease.
  
  
  METHODS
  Magnetic resonance imaging of 87 individuals (72% male, average age 19±6 y) from 2 centers (29 consecutive patients with Scheuermann disease and 58 controls) were retrospectively evaluated by 2 neuroradiologists. Spinal epidural fat (EF) at seventh thoracic vertebra (EF7), maximum EF (EFmax), dural sac diameter at T7 and at the level of maximum EF (DS7 and DSmax) were measured. EF ratios at T7 (EFR7) and at maximum EF (EFRmax) were calculated as EF/DS. Body mass index (BMI) for study population and kyphosis severity for the patients were recorded. Mann-Whitney, Spearman correlation, and χ tests were performed dependent on the variable in question.
  
  
  RESULTS
  EF7, DS7, EFmax, EFR7, and EFRmax was significantly higher among patients with Scheuermann disease (EFmax 5.7±2.4 mm) than among controls (EFmax 3.8±1.1 mm), P<0.001. Twelve patients with Scheuermann disease (41%) fulfilled our proposed criteria for the diagnosis of SEL (EFmax>6 mm+EFRmax>0.51) compared with 2 (3%) among controls (P<0.001). Patients with Scheuermann disease exhibited higher BMI than controls (24.9±5 kg/m vs. 22.9±4 kg/m, P=0.138). Logistic regression showed that the occurrence of SEL among patients with Scheuermann disease was independent of BMI (P=0.880). The degree of kyphosis in patients with Scheuermann's disease (62±20°) was correlated to the amount of the EF.
  
  
  CONCLUSIONS
  As SEL occurs more frequently among patients with Scheuermann disease, spine magnetic resonance imaging should be routinely performed to screen each of these patients to avoid impending neurological injury during surgery, especially in those exhibiting SEL.
authors.affiliation: Faculty of Medicine, Lund University, Malmö, Sweden. kasim.abul-kasim@med.lu.se
authors.forename: Kasim
authors.initials: K
authors.lastname: Abul-Kasim
authors.forename: Dietrich
authors.initials: D
authors.lastname: Schlenzka
authors.forename: Eufrozina
authors.initials: E
authors.lastname: Selariu
authors.forename: Acke
authors.initials: A
authors.lastname: Ohlin
mesh_terms: D000293:Adolescent; D000328:Adult; D004824:Epidural Space / Q000473:pathology*; D005260:Female; D006801:Humans; D008068:Lipomatosis / Q000150:complications / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D012544:Scheuermann Disease / Q000150:complications / Q000473:pathology*; D013904:Thoracic Vertebrae / Q000473:pathology*