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How do gigantism and dwarfism result from altered growth patterns?

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Fetal growth — human development Growth of the human fetus from the fourth month to the ninth month of pregnancy.

Gigantism and dwarfism are conditions resulting from altered growth patterns, primarily driven by endocrine disorders, hereditary factors, or metabolic issues that affect skeletal development.12

Gigantism

Gigantism is characterized by excessive stature beyond normal hereditary and environmental expectations. It is typically caused by:1
* Pituitary Gigantism: Hypersecretion of growth hormone during childhood or adolescence, often due to a pituitary gland tumor, which occurs before the closure of the bone epiphyses.13
* Androgen Deficiency: A lack of androgen can delay epiphyseal closure, prolonging the period of bone growth.1

Dwarfism

Dwarfism involves significant growth retardation resulting in abnormally short stature. Causes include:2
* Hormonal Deficiency: Pituitary dwarfism results from a lack of growth hormone. Similarly, inadequate thyroid hormone can lead to growth retardation.24
* Hereditary Conditions: Disorders such as achondroplasia involve disturbances in the bone-producing cells of the growth plates, leading to disproportionate limb growth.2
* Metabolic and Nutritional Factors: Conditions like rickets or severe emotional deprivation can also impede normal growth.25

In both cases, the timing of these disruptions relative to skeletal maturity—specifically the closure of the epiphyses—determines the final physical manifestation.13