A doctor examining the ankle of a patient

Learn About the Amazing Fundamentals of Fracture Healing

A fracture can take time to heal, but the good news is that, unlike other injuries, it heals without leaving a scar.1,2 And once you understand how fractured bones mend themselves, you will be astounded by your body’s healing abilities. Let’s take a closer look to understand the process of fracture healing. 
 

Stages of Bone Healing

Fractures mostly heal well, allowing you to resume your normal activities. However, in some cases, the fractured bone does not heal properly resulting in a condition termed as malunion.5

Malunion occurs when the broken ends of your bone are not aligned. Hence, while treating a fracture, your doctor may either use a non-surgical approach (cast or splint) or a surgical approach to keep the broken bone in line and stable.4 Fracture healing is thus a complex physiological process.

Illustration of clot formation at the fracture site

Clot Formation (First 5 Days)

When a fracture occurs, the blood vessels surrounding the bone are torn, leading to the formation of a blood clot at the fracture site.3 Inflammation (redness, swelling, and pain) is induced by your body's defense mechanism. Some of the cells causing inflammation gather at the site of injury to remove the damaged and dead tissues, allowing the healing process to begin.4
 

Illustration of soft bone formation

Callus Formation (Day 5 To Day 28)

A soft bone (soft callus) replaces the blood clot approximately within about a week (5-11 days) following the fracture. Although this soft callus maintains the bone together, it is not strong enough.3 The soft callus hardens and gets stronger (becomes a bony callus) after a few weeks.4
 

Illustration of bone remodeling

Remodeling (Day 18 To Months)

The bony callus undergoes remodeling at this stage. This process might take months to complete, but it eventually leads to the restoration of normal bone structure.3
 

References

1. Marsell R, Einhorn TA. The biology of fracture healing. Injury. 2011; 42(6): 551–555.
2. Dimitriou R, Jones E, McGonagle D, et al. Bone regeneration: current concepts and future directions. BMC Med. 2011;9:66.
3. AAOS. Orthoinfo. Fractures. How Broken Bones Heal. [Internet] [Cited 24 Jan 2022] Available from: orthoinfo.aaos.org
4. Sheen JR, Garla VV. Fracture Healing Overview. Statpearls [Internet] [Cited 24 Jan 2022] Available from: www.ncbi.nlm.nih.gov
5. Cleveland Clinic. Foot & Ankle Fractures Malunion. [Internet] [Cited 24 Jan 2022] Available from: my.clevelandclinic.org

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