Injury & Inflammation
Soft Callus Formation
Hard Callus Formation
Bone Remodeling
General Bone Facts
100

What forms right after the bone breaks?

A hematoma (blood clot)

100

What replaces the hematoma during this stage?

A soft callus made of cartilage and collagen.

100

What type of tissue replaces the soft callus?

Spongy bone tissue.

100

What happens during this final stage?

The bone reshapes to look normal again.

100

What type of tissue makes up bones?

Connective tissue.

200

Which cells come to clean up the area?

White blood cells (and osteoclasts)

200

Which cells start to rebuild tissue?

Chondroblasts and fibroblasts.

200

Which cells build new bone?

Osteoblasts.

200

Which two cells work together here?

Osteoblasts (build) and osteoclasts (remove old bone).

200

What gives bones their hardness?

Calcium and minerals.

300

How does this stage help the bone heal?

It brings nutrients and clears out damaged cells.

300

Why is this called the “soft” callus?

Because it’s flexible and not yet bone.

300

What’s the hard callus made of?

Trabeculae (tiny bone structures).

300

What happens to the bone’s strength?

It becomes just as strong as before.

300

What is the name of a bone cell?

Osteocyte.

400

What does the injury look like inside the foot during this stage?

Broken bone ends separated, swelling, and bleeding.

400

About how long after the injury does this stage begin?

Around 1–3 weeks.

400

How does the bone look now?

It’s connected again but still weak.

400

What kind of bone replaces the spongy bone?

Compact bone.

400

What connects bones to muscles?

Tendons.

500

Why is inflammation actually a good thing here?

It triggers the healing process by signaling repair cells.

500

What holds the bone together during this time?

The soft cartilage bridge.

500

How long can this stage last?

6 to 12 weeks

500

How long can full remodeling take?

Several months to a year.

500

What connects bones to other bones?

Ligaments.