title: Thickness of the ligamentum flavum: correlation with age and its asymmetry-an magnetic resonance imaging study.
abstract: METHODS
  A retrospective radiological study of the ligamentum flavum (LF).
  
  
  OBJECTIVE
  This study is an attempt to measure and compare the thickening of the LF on both the sides with the use of magnetic resonance imaging, to investigate if there is a predominant tendency to thicken a specific side and also to determine if a correlation between the thickening of the LF and increasing age exists.
  
  
  BACKGROUND
  Even though many studies measured the thickness of the LF, very few have compared it on each side, or determined its correlation with age.
  
  
  METHODS
  The thickness of LF was measured at the L3-4, L4-5, L5-S1 levels on both sides using the magnetic resonance images of 200 patients (n=1,200). The sample population was divided into three groups: 21-40 years, 41-60 years, and 61-80 years. The data was analyzed statistically, comparing the thickness of LF on both sides and in various age-groups.
  
  
  RESULTS
  The thickness of the LF was found to increase with age; however, there were several younger instances with thicknesses >4 mm. The mean thickness of the right LF at different spinal levels was measured (L3-L4=3.38±0.94 mm, L4-L5=3.70±1.16 mm, and L5-S1=3.65±1.16 mm) while the mean thickness of the left LF was higher (L3-L4=3.52±0.99 mm, L4-L5=3.84±1.12 mm, and L5-S1=3.78±1.24 mm).
  
  
  CONCLUSIONS
  The LF thickness does not appear to have any side dominance; however, it tends to thicken with increasing age.
authors.affiliation: Department of Anatomy, Topiwala National Medical College, B.Y.L. Nair Charitable Hospital, Mumbai, India.
authors.forename: Vrushali Subhash
authors.initials: VS
authors.lastname: Kolte
authors.affiliation: Department of Anatomy, Topiwala National Medical College, B.Y.L. Nair Charitable Hospital, Mumbai, India.
authors.forename: Seema
authors.initials: S
authors.lastname: Khambatta
authors.affiliation: Department of Anatomy, Topiwala National Medical College, B.Y.L. Nair Charitable Hospital, Mumbai, India.
authors.forename: Medha Vijay
authors.initials: MV
authors.lastname: Ambiye
keywords: Age; Asymmetry; Ligamentum flavum; MRI measurements; Spinal canal stenosis