The Epiphyseal Plate

The Epiphyseal Plate

A cartilaginous “growth” plate located between the ends of bones

(the epiphysis and the metaphysis) which allows for lengthwise bone growth

4 Zones of the Epiphyseal Plate

1. Zone of Resting Cartilage

-toward Diaphysis

               -small, scattered chrondrocytes that anchor or glue the epiphyseal plate

                to the epiphysis

2. Zone of Proliferating Cartilage

               -dividing chrondrocytes, scattered and stacked

3. Zone of Hydrotrophic (growing) Cartilage

               -chrondrocytes growing

               -stacked in columns for lengthwise growing

4. Zone of Calcified Cartilage (adjacent to Diaphysis)

            -mineral salts deposited in cartilage matrix which changes it to bone

There are 2 Different ways that bone forms:

1. Intamembranous Ossification

-future bone begins as a fibrous connective tissue membrane and  changes into a bone.  Example:  Skull

2. Endochondral Ossification

               -future bone begins as a hyline cartilage model

               - the most common way bones are formed

               -Example: Epiphyseal Plate