Anatomical age is the numerical assessment of a child's physical growth in relation to the statistical average based on the child's chronological age.
Using statistical data, the American Academy of Pediatrics and the National Institutes of Health in the United States have developed tables to illustrate the growth patterns of children. These tables describe the population of all children of a certain age, with ranges for weight, height, and other physical characteristics. For most children, anatomical age—based on weight and height measurements—is the same as chronological age—based on the number of months or years since birth. However, when a child's physical growth falls outside the range of his chronological age, the child's age is determined by his growth. For example, if a six-year-old's height and weight falls within the range for five-year-olds, his anatomical age will be given as five, not six years.
Anatomical age has been used as a determination of chronological age by immigration and adoption agencies when no birth certificates have been available. This has been crucial for refugee children in particular. However, prolonged malnutrition can cloud actual age assessments. That is why radiographs, or x rays , of a child's bones have been taken and read by osteologists (doctors who special in the skeletal system) and radiologists.
William Walter Greulich and S. Idell Pyle's atlas of skeletal development and Tanner and White's method are the two major assessment tools for wrist radiography. X rays of a child's left wrist are compared visually with a series of x rays of wrists of children of various ages. A computerized system has been developed based on Tanner and Whitehouse's model, which uses pattern recognition like finger print databases. This technique greatly speeds up the diagnostic process.
In addition, an ultrasound version of the Greulich-Pyle Atlas has proven to be as effective as wrist x rays. This method does not expose children to radiation.
Standardized growth charts and wrist radiographs can assess normal skeletal growth and determine whether there are problems concerning growth that is too fast or too slow. Anatomical age assessment can also reveal other conditions. Because bone growth is affected by calcium regulating hormones, sex steroids, and thyroid hormones, disturbances in the endocrine system, which controls hormones, can be detected.
Determining anatomical age can give parents an indication of their children's future growth and can help them work with their doctors to determine treatment if there seem to be growth problems.
When to call the doctor
Usually, the child sees the doctor for immunizations, school physical exams, or childhood illnesses. At these times, the doctor may discuss findings about anatomical age with parents. If parents have concerns about their children's growth, they can bring them up at these visits.
Osteologist —A doctor who specializes in the skeletal system.
Radiograph —The actual picture or film produced by an x-ray study.
See also X rays .
Hochberg, Ze'ev. Endocrine Control of Skeletal Maturation. Farmington, CT: S. Karger Publishers, 2002.
Flores-Mir, C., et al. "Use of Skeletal Maturation Based on Hand-Wrist Radiographic Analysis as a Predictor of Facial Growth: A Systematic Review." Angle Orthodontia 74, no. 1 (February 2004): 118–24.