Bone Growth and Remodeling of Bones | Novice Medic

Bone formation is not complete at birth; many membranous and cartilaginous bones continue to grow and remodel for years, often until early adulthood. Membranous bones of the skull, for example, have membranes that allow the skull to grow in size over time.

Growth plates, or epiphyseal cartilages, are located between the diaphysis and epiphysis of long bones. This cartilage continuously grows, forming new bone tissue at the diaphyseal end, allowing bones to grow in length during youth.

The inner layer of the periosteum in the diaphysis of long bones contains osteoprogenitor cells. These transform into osteoblasts, which deposit new bone, causing long bones to grow in diameter.

As a body matures, growth plates stop growing, narrow, and eventually disappear. This leads to the fusion of the diaphysis with the epiphysis, a process known as the closure of growth plates.

While osteoblasts in the periosteum increase bone shaft diameter, osteoclasts (bone-resorbing cells) remove bone tissue from inside the medullary cavity, contributing to bone remodeling.