Cortical bone measurements in Turner's syndrome

Area of Science:

• Endocrinology
• Genetics
• Orthopedics

Background:

• Turner syndrome is a genetic condition affecting females, characterized by various physical stigmata.
• Bone health is a concern in Turner syndrome, with potential implications for osteoporosis.
• Previous studies suggest alterations in bone metabolism in individuals with Turner syndrome.

Purpose of the Study:

• To evaluate cortical bone dimensions in the second metacarpal in individuals with Turner syndrome.
• To compare these measurements with normal female standards across different bone ages.
• To investigate the influence of karyotype, clinical features, and estrogen status on bone dimensions.

Main Methods:

• Retrospective analysis of 156 hand X-rays from 80 individuals with Turner syndrome (age 1-25).
• Measurements included total shaft width, medullary width, cortical width, and percent cortical area at the second metacarpal midshaft.
• Comparison with age- and sex-matched normal female standards, grouped by bone age.

Main Results:

• Total shaft width was significantly below normal and decreased with age.
• Cortical width was significantly lower from age 14, with a rise at adult bone age (17).
• Percent cortical area was reduced at ages 14-15 but normalized in adulthood, not indicating severe osteoporosis.
• No significant differences in bone measurements were found based on karyotype variants or presence of typical Turner stigmata.
• Estrogen treatment or menarche was associated with significant increases in cortical width and percent cortical area.

Conclusions:

• Individuals with Turner syndrome exhibit reduced cortical bone width, particularly in adolescence.
• Bone density in Turner syndrome, as assessed by percent cortical area, appears to normalize in adulthood and does not suggest widespread osteoporosis.
• Estrogen plays a crucial role in bone development and maintenance in Turner syndrome, with treatment or menarche showing positive effects.