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Relationship between head dimensions and body length in the context of mental retardation

M Jaffe1, E Tirosh, R Pollak

  • 1Hannah Khoushy Child Development Center, Haifa City Medical Center (Rothschild), Technion-Israel Institute of Technology, Israel.

Israel Journal of Medical Sciences
|January 1, 1988
PubMed

Insights

Mentally retarded children show reduced head length and body length compared to controls. This indicates general growth failure rather than disproportionate head size in normocephalic individuals.

Area of Science:

  • Pediatrics
  • Developmental Biology
  • Genetics

Background:

  • Cranial and body dimensions are key indicators of child development.
  • Previous studies have explored the relationship between head size and developmental status, with some suggesting disproportionate head growth in certain conditions.
  • Normocephalic mentally retarded children present a unique group for studying growth patterns.

Purpose of the Study:

  • To investigate the relationship between cranial dimensions (head length, head circumference, biparietal diameter), body length, and developmental status in normocephalic children.
  • To determine if a disproportionate head size exists in mentally retarded children compared to their body length.
  • To identify key growth parameters that differentiate between mentally retarded and normal children.

Main Methods:

  • A comparative study involving 166 mentally retarded children and 471 normal controls, aged 3 months to 6 years.
  • Measurement of head length, head circumference, biparietal diameter, and body length.
  • Statistical analysis, including discriminant analysis, to identify significant differences and predictive factors.

Main Results:

  • All measured dimensions, especially head length, were significantly reduced in the mentally retarded group compared to controls.
  • In younger children (3-15 months), head length was the most affected dimension; in older children, body length and then head length were most significant.
  • Discriminant analysis identified body length, head length, and age as significant factors, while head circumference and biparietal diameter were not contributory.

Conclusions:

  • The study does not support the concept of disproportionately small head size relative to height in normocephalic mentally retarded children.
  • Findings suggest a general growth failure affecting both body length and head length in this population.
  • Body length and head length are critical indicators of growth deficits in normocephalic children with intellectual disabilities.

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