Age and sex dependency of cartilage T2 relaxation time mapping in MRI of children and adolescents

AJR Am J Roentgenol. 2014 Mar;202(3):626-32. doi: 10.2214/AJR.13.11327.


Objective: T2 relaxation times on MRI are sensitive to the configuration of cartilage collagen and continually increase during aging in adults. In children, T2 relaxation times increase as a result of cartilage microstructure changes in early inflammatory arthritis. The purpose of this study was to determine age- and sex-related differences in T2 mapping of the patellar cartilage in children and adolescents during normal skeletal maturation.

Materials and methods: Ninety-seven subjects (age range, 5-22 years; 51 females and 46 males; mean age, 14.3 and 13.7 years, respectively) without patellofemoral instability or inflammatory arthritis were included. All subjects underwent 1.5-T knee MRI with T2 mapping. The mean T2 relaxation time and thickness of the patellar cartilage were documented for each MRI examination. Skeletal maturation was determined by physeal patency (open; or closed or closing) on MRI. The associations between T2 relaxation times, cartilage thickness, sex, age, and physeal patency were assessed using Wilcoxon rank sum test and least-squares means regression models.

Results: T2 relaxation times and thickness of the patellar cartilage significantly decreased (p<0.0001) with increasing chronologic age. T2 relaxation times and cartilage thickness in the open physis group were found to be greater than in the closed or closing physis group (p<0.0001). T2 relaxation times and cartilage thickness were greater in males than in females (p<0.05).

Conclusion: In contrast to senescent changes in adults, skeletal maturation in children results in a sequential decrease in T2 relaxation times that are age- and sex-dependent. Similar to cartilage in adults, cartilage in children gets progressively thinner during skeletal maturation.

MeSH terms

  • Adolescent
  • Age Distribution
  • Aging / pathology*
  • Cartilage, Articular / pathology*
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Image Interpretation, Computer-Assisted / methods*
  • Magnetic Resonance Imaging / methods*
  • Magnetic Resonance Imaging / statistics & numerical data*
  • Male
  • Ohio / epidemiology
  • Patella / pathology*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Sex Distribution
  • Sex Factors
  • Young Adult