title: CT morphometry of adult thoracic intervertebral discs.
abstract: OBJECTIVE
  Despite being commonly affected by degenerative disorders, there are few data on normal thoracic intervertebral disc dimensions. A morphometric analysis of adult thoracic intervertebral discs was, therefore, undertaken.
  
  
  METHODS
  Archival computed tomography scans of 128 recently deceased individuals (70 males, 58 females, 20-79 years) with no known spinal pathology were analysed to determine thoracic disc morphometry and variations with disc level, sex and age. Reliability was assessed by intraclass correlation coefficients (ICCs).
  
  
  RESULTS
  Anterior and posterior intervertebral disc heights and axial dimensions were significantly greater in men (anterior disc height 4.0±1.4 vs 3.6±1.3 mm; posterior disc height 3.6±0.90 vs 3.4±0.93 mm; p<0.01). Disc heights and axial dimensions at T4-5 were similar or smaller than at T2-3, but thereafter increased caudally (mean anterior disc height T4-5 and T10-11, 2.7±0.7 and 5.4±1.2 mm, respectively, in men; 2.6±0.8 and 5.1±1.3 mm, respectively, in women; p<0.05). Except at T2-3, anterior disc height decreased with advancing age and anteroposterior and transverse disc dimensions increased; posterior and middle disc heights and indices of disc shape showed no consistent statistically significant changes. Most parameters showed substantial to almost perfect agreement for intra- and inter-rater reliability.
  
  
  CONCLUSIONS
  Thoracic disc morphometry varies significantly and consistently with disc level, sex and age. This study provides unique reference data on adult thoracic intervertebral disc morphometry, which may be useful when interpreting pathological changes and for future biomechanical and functional studies.
authors: Department of Anatomy, University of Otago, Dunedin, New Zealand.
authors: Justin G R
authors: JG
authors: Fletcher
authors: Department of Anatomy, University of Otago, Dunedin, New Zealand.
authors: Mark D
authors: MD
authors: Stringer
authors: Department of Anatomy and Cell Biology, University of Melbourne, Melbourne, Australia.
authors: Christopher A
authors: CA
authors: Briggs
authors: Department of Mathematics and Statistics, University of Otago, Dunedin, New Zealand.
authors: Tilman M
authors: TM
authors: Davies
authors: Department of Anatomy, University of Otago, Dunedin, New Zealand. stephanie.woodley@anatomy.otago.ac.nz.
authors: Stephanie J
authors: SJ
authors: Woodley
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012015:Reference Standards; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: Age; Computed tomography; Intervertebral disc; Morphometry; Thoracic spine