How Much Force Does It Take To Break A Bone?

Summary

This DNews episode explores the complexity of bone fractures, highlighting the differences in force required to break various bones due to their size and structure. Dr. Cindy Bir explains that the femur can withstand around 4,000 newtons of force compared to the rib's 3,300 newtons, influenced by muscle support and bone tissue composition. Factors such as diet, exercise, and age also affect bone strength, with a decline in bone density post-age 30 potentially leading to osteoporosis.

Takeaways

• 🦴 Humans have 206 bones, varying in shape and size, which affects their susceptibility to breaking.
• 💪 The femur, being the largest bone, is harder to break compared to the more slender clavicle, which is commonly broken.
• 🏋️ Muscle support around a bone plays a role in absorbing impact and protecting it from fractures.
• 🔢 An estimated force of 3,300 newtons has a 25% chance of breaking a rib, while the femur requires around 4,000 newtons.
• 👊 The angle of impact is crucial; a perpendicular blow is more damaging than a parallel one due to bone structure.
• 🦴 Bones consist of two types of tissue: cancellous (spongy inner material) and cortical (dense outer layer).
• 🧬 Cortical bone, which makes up 80% of the skeleton's mass, is composed of collagen and calcium phosphate for strength and flexibility.
• 🤸‍♂️ Bones are dynamic, undergoing a constant process of resorption and rebuilding, influenced by diet, exercise, and age.
• 🥦 A diet low in calcium can lead to brittle bones, while exercise can strengthen them by stressing the bone structure.
• 👵 Bones reach peak density around age 30 and decline thereafter, increasing the risk of osteoporosis with age.
• 🧑‍🦳 In the US, 55% of people over 50 are estimated to have osteoporosis, which weakens bones and makes them prone to fractures.
• 🎥 The video also mentions a new Seeker VR channel for an immersive video experience using VR devices.

Q & A

What incident during the filming of a Star Wars movie prompted the discussion on bone strength?

A hydraulic door broke Harrison Ford's leg, which led to the discussion on how much force it takes to break a bone.

How many bones do adults typically have in their body?

Adults have 206 bones in their body, which come in various shapes and sizes.

Which is the largest bone in the human body and why is it harder to break?

The femur, or thigh bone, is the largest bone in the human body. It is harder to break due to the muscle mass surrounding it that helps absorb impact.

What is the role of muscle around a bone in terms of bone strength?

Muscles around a bone support the bone and absorb some of the impact from a hit, providing additional protection against fractures.

What is the estimated force required to have a 1 in 4 chance of cracking an average person's rib according to Dr. Cindy Bir?

Dr. Cindy Bir estimates that a force of 3,300 newtons has a 1 in 4 chance of cracking an average person's rib.

How does the angle of force application affect the likelihood of breaking a bone?

A blow perpendicular to the bone does more damage than the same force applied almost parallel because of the bone's structure.

What are the two types of bone tissue that make up human bones?

The two types of bone tissue are cancellous bone, which is the spongy inner material, and cortical bone, which is the dense, hard, and stiff outer layer.

Why are bones good at handling compressive forces but not shear forces?

Bones are good at handling compressive forces due to their columnar structure, but they are not as effective at dealing with shear forces because of the way the collagen and calcium phosphate are arranged.

How does diet, particularly calcium intake, affect the strength of bones?

A diet low in calcium can lead to more brittle bones because calcium is a major component of bones, and its deficiency can compromise bone strength.

What is the impact of exercise on bone strength and why is it important for astronauts?

Exercise puts stress on bones, which can make them stronger. Astronauts experience reduced bone density in space because the lack of gravity means their bones aren't getting the stress they would on Earth.

Why do bones become weaker with age and what condition can this lead to?

Bones reach peak density around age 30 and then begin to decline as the resorption of bone happens faster than formation, which can eventually lead to osteoporosis, a condition where bones are weaker and more prone to fractures.

What percentage of people over 50 in the US are estimated to have osteoporosis?

In the US, an estimated 55% of people over 50 have osteoporosis.

Outlines

00:00

🦴 The Complexity of Bone Fracture

This paragraph explores the intricacies of bone fractures, sparked by the incident where Harrison Ford's leg was broken by a hydraulic door during a Star Wars film shoot. It explains that the human body, comprising 206 bones of various shapes and sizes, has varying fracture thresholds. The femur, being the largest bone, is notably more resilient than the more slender clavicle, which is frequently broken. The paragraph delves into the role of muscle support in bone protection, the impact of force application direction on damage, and the structural composition of bones, including cancellous and cortical tissues. It also touches on factors influencing bone strength, such as diet, exercise, and age, and mentions the dynamic nature of bones and the risk of osteoporosis with aging.

Keywords

💡Bone

A bone is a rigid connective tissue that forms part of the endoskeleton of vertebrate animals, providing support, structure, and protection for the body. In the context of the video, bones are the central theme, as the script discusses the force required to break them and the various factors that influence their strength and susceptibility to fractures.

💡Femur

The femur, also known as the thigh bone, is the longest, strongest, and heaviest bone in the human skeleton. The video mentions the femur as an example of a bone that is harder to break due to its size and the amount of muscle surrounding it, which can absorb impact.

💡Clavicle

The clavicle, or collarbone, is a long bone that serves as a strut between the shoulder blades and the sternum. The script points out that the clavicle is one of the more commonly broken bones, likely due to its relative thinness and less muscle support compared to larger bones like the femur.

💡Muscle

Muscles are soft tissues that contract to produce movement. In the video, muscles are highlighted for their role in supporting bones and absorbing some of the impact from a hit, which can prevent or reduce the likelihood of bone fractures.

💡Force

Force is a push or pull upon an object resulting from its interaction with another object. The video script explores the concept of force in relation to bone fractures, providing specific measurements in newtons that can potentially break ribs and femurs.

💡Newtons

Newtons are a unit of measurement for force in the International System of Units (SI). The script uses newtons to quantify the force required to break bones, with 3,300 newtons being the force that has a 1 in 4 chance of cracking a rib, and around 4,000 newtons for the femur.

💡Cancellous Bone

Cancellous bone, also known as spongy bone, is the lighter, less dense bone found at the ends of long bones and in the inner layer of flat bones. The video explains that cancellous bone contains red bone marrow and contributes to the overall structure and function of bones.

💡Cortical Bone

Cortical bone, also referred to as compact bone, is the dense, hard, and stiff bone that forms the outer layer of bones. It accounts for 80% of the skeleton's mass and is composed of collagen and calcium phosphate, providing strength and rigidity to the bones.

💡Resorption

Resorption is the process by which bone tissue is broken down and removed, typically in the context of bone remodeling. The video mentions that bones are dynamic, with a balance between resorption and rebuilding, and a diet low in calcium can affect this process, leading to weaker bones.

💡Osteoporosis

Osteoporosis is a medical condition characterized by bones becoming brittle and fragile from loss of tissue, typically as a result of hormonal changes or deficiency of calcium. The video script notes that osteoporosis can increase the risk of fractures and is prevalent among older individuals in the US.

💡Bone Density

Bone density refers to the amount of bone mineral content, an indicator of bone strength and resistance to fracture. The video script mentions that bone density can be reduced due to lack of stress on the bones, as experienced by astronauts in space, leading to weaker bones.

Highlights

The force required to break a bone is more complex than it seems due to the variety of bone shapes and sizes.

The femur, being the largest bone, is harder to break compared to the more slender clavicle.

Muscles around a bone support it and absorb impact, making some bones more resilient to damage.

Dr. Cindy Bir estimates 3,300 newtons have a 25% chance of breaking a rib, while the femur requires around 4,000 newtons.

The way force is applied affects bone breakage, with perpendicular impacts being more damaging than parallel ones.

Bones consist of cancellous and cortical tissues, with the latter providing the majority of bone strength.

Cortical bone's structure of collagen and calcium phosphate columns provides strength along the bone's length.

Bones are adept at handling compressive forces but are less resistant to shear forces.

Individual bone strength can vary based on diet, age, and lifestyle factors.

Bones are dynamic, undergoing a constant process of resorption and rebuilding, influenced by calcium intake.

Exercise can strengthen bones by applying stress, in contrast to the bone density loss experienced by astronauts in space.

Bone density peaks around age 30 and declines thereafter, potentially leading to osteoporosis.

Osteoporosis affects an estimated 55% of people over 50 in the US, causing bones to fracture more easily.

Seeker has launched a new Seeker VR channel for an immersive video experience.

A humorous note on the misconception that men might have an additional bone.

A personal question inviting viewers to share their experiences with bone fractures.

Transcripts

What does it take to break a bone?

Like, really…

Could I do it with my bare hands?!

Hello there skeletal-based humans!

Amy here for DNews.

Recently it came out that during the filming of the latest Star Wars movie, a hydraulic

door broke Harrison Ford’s leg.

This got us wondering: how much force does it take to break a bone?

As it turns out that question is a lot more complicated than it sounds.

Adults have 206 bones that come in a lot of shapes and sizes, so some bones are going

to be a lot easier to break than others.

The largest bone in your body, your femur or thigh bone, is a lot harder to break than

the long slender clavicle, or collarbone, which one of the more commonly broken bones.

Part of this has to do with the of muscle around a bone that supports the bone and absorbs

some of the impact from a hit.

Your femur encased in all your leg meat, and that can take more of a hit than your rib.

Dr Cindy Bir of the University of Southern California estimates that a force of 3,300

newtons has a 1 in 4 chance of cracking the average person’s rib, while their femur

typically takes more force to break: around 4,000 newtons.

There isn’t a set number for what force will break a bone like a rib because how the

force is applied makes a difference.

A blow perpendicular to the bone is going to do more damage than when that same force

is applied almost parallel, and that’s because of how bones are built.

Your bones are actually made up of two types of bone tissue: cancellous bone and cortical

bone.

Cancellous bone is the spongy inner material and usually contains red bone marrow that

makes red blood cells.

Cortical bone, also called compact bone, makes up the outside.

It’s dense, hard, stiff, and accounts for 80% of your skeleton’s mass.

This outer layer is made up of columns of of collagen and calcium phosphate, like bundles

of twigs.

Collagen provides the soft framework in the bones and calcium phosphate adds the strength.

Because these columns run vertically, they give your bones strength down their length.

Bones are great at taking compressing forces like when you jump but can’t deal too well

with shear forces like when someone hits you with a car.

Certain people might also just have stronger bones, depending on their diet, age, and lifestyle.

Your bones are dynamic: they’re constantly being broken down in a process called resorption,

and rebuilt.

Because a big component of them is calcium, a diet low in calcium means your bones will

probably be a bit more brittle.

And just like with muscle, putting stress on your bones through exercise can make them

stronger.

That’s why astronauts come back from space with reduced bone density: floating around

up there means their bones aren’t getting the same stress they would on earth.

But even if your diet and exercise routines are great, there’s no fighting age.

Our bones reach a peak density around age 30 and then begin to decline when the resorption

of bone happens faster than formation.

Eventually this can lead to osteoporosis, a condition where bones are weaker and can

fracture more easily, sometimes even under normal use.

In the US, an estimated 55% of people over 50 have osteoporosis.

If you’re a fan of 360 and VR videos, Seeker has launched our brand new Seeker VR channel

perfect for watching your favorite videos using the YouTube app or VR device.

So put on your headphones and get ready to experience videos in a whole new way!

So, when I said the human body has 206 bones, I bet some of you said dudes can have 207.

Way to be immature, and no they can’t.

But other animals can!

Laci talks about penis bones here.

Have you ever broken a bone?