Improving Bone Fracture Recovery via A Nanofibrous Scaffold

An in vivo approach

In about March of 2022, I broke my left femur and was rushed to the ER. The surgeon told me I was going to have an operation the next morning to fix the fracture. They were going to place a rod on the side to stabilize the two bones and from there, let the bone heal on its own. Post-surgery, they said the recovery time was looking like 2 weeks of limited movement, 1 month on crutches, 4 months before regular physical activity.

Now as an avid runner and athlete, this sucked. This long of a recovery time was devasting and sadly nothing was going to be able to speed it up. I just had to sit and wait. Luckily, I had youth on my side meaning my recovery was going to be a lot faster than most. And having gone through this lengthy process I realized there was an actual need to improve fracture healing because the recovery time puts too much of a hold on one’s life when there’s so much to do in the world.

Brief Overview of Fracture Healing

Let’s start the journey with a quick background in fracture healing. It all starts with an initial anabolic phase where local tissue volume increases through inflammation right after the fracture occurs — your body’s natural response.

A hematoma (blood clot) forms to act as a temporary scaffold for stem cell differentiation into fibrous tissue, cartilage, and bone. The giant blood clot will basically surround the fracture to provide temporary relief and form the basis of the healing.

In the inflammatory phase, many biological factors are released that regulate healing mechanisms and this is where we want to focus on later.

Cartilaginous callus (soft) is formed through the activities of skeletal and endothelial cells which bridge the gap between bone fragments. This is temporary in order to get the bone locked into the right place before the permanent bone forms as then the soft callus will turn into hard callus.

Now from here, there are 2 typical types of mechanisms of bone formation:

• Intramembranous ossification — MSCs differentiate to osteoblasts, creating bone tissue directly in the anabolic process (typical of flat bones like the hip bone)
• Endochondral ossification — MSCs differentiate into chondrocytes, which create cartilage tissue. Synthesized cartilage ECM mineralizes…