How do bones grow wider?

Bones grow wider through a process called radial growth. This process involves the formation of new bone tissue on the outer surface of the bone, while the inner surface of the bone is resorbed.

1. New bone tissue is formed by osteoblasts, which are cells that specialize in bone formation. Osteoblasts lay down new bone matrix, which is made up of collagen and calcium phosphate.

2. The inner surface of the bone is resorbed by osteoclasts, which are cells that specialize in bone resorption. Osteoclasts secrete enzymes that break down the bone matrix, releasing calcium and phosphate ions into the bloodstream.

3. The released calcium and phosphate ions are then used by osteoblasts to form new bone tissue.

The rate of radial growth is controlled by a number of factors, including:

* Hormones: Growth hormone and thyroid hormone promote radial growth, while sex hormones (estrogen and testosterone) inhibit radial growth.

* Nutrition: A diet rich in calcium and vitamin D is essential for radial growth.

* Exercise: Exercise can stimulate radial growth by increasing the demand for bone strength.

Radial growth typically occurs during childhood and adolescence, but it can continue into early adulthood. Once a person reaches skeletal maturity, radial growth stops and the bones stop growing wider.