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How Do Broken Bones Heal, and Why Does It Take Longer for Adults?

Category: The Body

Imagine you break a bone in your arm. It snaps with a sharp sound. Yet, after some time, you can move it again as if nothing happened. This is possible because bones are alive. They are constantly being rebuilt. When a bone breaks, this rebuilding process focuses on the break. Blood gathers at the site, forming a clot, which eventually turns into new bone.

This article explores how this repair happens. We will look at how we discovered the ability to see inside the body, the stages of healing, and why age changes the process.

1. How X-rays Let Us See Inside Bones

Today, if you hit your arm or leg hard, a hospital can take an X-ray. This image shows exactly what is happening to the bone inside. However, this technology is not ancient. It was developed relatively recently in history [1].

In 1895, a German scientist named Röntgen discovered a type of invisible light [1]. In December of that same year, Röntgen tried to photograph his wife’s hand using this new light [1]. The image clearly showed the bones inside her hand and the shape of her ring [1].

2. How the Body Rebuilds and Heals a Broken Bone

Bones continue to be rebuilt even after you become an adult. It is said that a bone is completely replaced over a period of 10 to 20 years [2]. The healing of a broken bone relies on this same power of rebuilding [2].

The healing process happens in stages. First, blood gathers at the break and forms a clot [2]. Next, this clot slowly changes into a soft "temporary bone" [2]. Finally, this temporary bone is carefully reshaped over time to match the hardness and shape of the original bone [2]. This final finishing stage can take several months [2].

3. Why Children's Soft, Flexible Bones Heal Faster

Children’s bones are softer and more flexible than adult bones [3]. Because of this, they do not always snap cleanly in two. Instead, they may break on one side only, similar to how a young tree branch bends and cracks [3]. This type of break is called a "wakagi" fracture [3].

There is another surprising fact about children’s bones. If a bone heals while slightly bent, it can straighten itself out on its own over about six months [3].

SAFETY NOTE: Deciding if a bone is broken is a job for a doctor. If you cannot move your arm or leg, or if you cannot put weight on it, do not judge the injury yourself. You must always go to a hospital for a proper examination [3].

4. Why Adults' Bones Take Longer to Heal

Compared to children, adults take more time for their bones to join back together [4]. This is especially true for older people [4]. As people age, the density inside the bone decreases, and blood circulation becomes poorer [4]. Because of these changes, it is thought that older people take longer to heal than younger people [4].

The speed of healing varies greatly. It depends on the location of the break and the overall condition of the body [4].

5. Asking Family and Friends About Their Broken Bones

You can learn more about this process by asking people around you. Ask your family or friends if they have ever broken a bone. If they have, ask them how long it took to heal and how it healed . Hearing their stories can make the science of bone healing feel more real and interesting.

Sources

  1. Siemens Healthineers Japan, "'Röntgen Must Have Gone Mad'" https://www.siemens-healthineers.com/jp/news/x-ray-technoligy-roentgen.html (Röntgen discovered X-rays on November 8, 1895, and photographed his wife’s hand on December 22, showing bones and a wedding ring.)
  2. Tsurumaki Onsen Hospital, "Things You Should Know About the Body: Fractures" https://www.sankikai.or.jp/tsurumaki/disease/karada/karada7.html (Healing involves inflammation, repair, and remodeling; remodeling takes months to over a year; children’s bones can correct angles up to 15-30 degrees in six months.)
  3. Japanese Orthopaedic Association, "Fractures in Children" https://www.joa.or.jp/public/sick/condition/infants_bone_fracture.html (Growing bones are elastic; greenstick fractures are common; children have high self-correction power; see a doctor if movement or weight-bearing is impossible.)
  4. Rehasaku, "How Many Weeks Does It Take to Heal a Fracture?" https://rehasaku.net/magazine/body/fracture-time-takes-for-bones-heal (Older adults heal slower due to lower bone density and blood flow; healing time varies by location, age, and lifestyle.)