L7 Cellular Activity of Bone Tissue

It takes about 6 weeks for the fibrocartilage in a fetus to begin developing into bones(ossification.)

The [blank_start]diaphysis[blank_end] of long bones is the [blank_start]primary[blank_end] centre of ossification. The [blank_start]secondary centres[blank_end] occur in the [blank_start]epiphysis[blank_end]. These are separated by the epiphyseal plate, which is initially cartilaginous but becomes bone later in life.

The process of bone growing in width is called moulding.

During moulding: (Choose ALL CORRECT statements.)

In children, the medullary cavity is full of yellow marrow to facilitate the continuous growth, while in adults the medullary cavity is filled with red marrow.

Red marrow is red as it is highly vascularised.

What is epiphyseal fusion?

Bone pathology:

Osteoporosis is the weakening of the bone due to porousness, caused by osteoblastic activity overtaking osteoclastic activity.

Weakening of cancellous bone commonly leads to compression fractures.

Which of these is not a cause or contributing factor to risk of osteoporosis?

Assign these stages of a fracture with a time frame: A hematoma forms, capillaries growing into it and phagocytes cleaning up debris, [blank_start]immediately[blank_end]. Chondroblasts form a soft procallus of cartilage, [blank_start]within 3 days[blank_end]. Osteoblasts ossify the callus into a bony callus, [blank_start]by 6 weeks.[blank_end] Normal activity remodels the bone in the following weeks, or potentially [blank_start]years[blank_end] until the callus has disappeared (generally in adults.)

Not fixing a fracture results in pseudoarthrosis.

Which fracture has the most potential risk?