The Mechanics Of Bone Strength - Part 2 - Save Our Bones

In Part 1 of our series about bone strength, you learned about mechanical load. Today we'll look at the other half of the equation: the mechanical behavior of bone. When we talk about bone strength, we refer not just to the structure of bone, but to how it behaves under stress and strain.

By understanding the material and structural properties of bone, we can learn what makes bones resilient and resistant to damage and fracture. This information also sheds light on the detrimental effects of osteoporosis drugs.

Despite what patients are told, bone density is not the only parameter for measuring bone strength.

The Composition Of Bone

Bone is a complex tissue. It is composed of both organic components and inorganic components. The balance of these materials plays a significant role in determining bone's mechanical behavior and strength.

Two important measures of a bone's composition are mineralization and porosity. Taken together, they describe the apparent density of bone.

Mineralization describes how much of a bone's mass is composed of mineral material. Porosity describes the presence of pores within the bone matrix– the amount of bone composed with the spaces between that mineral material. Those spaces contain the organic material of bone, primarily collagen.1

The distribution of mineral material and porosity plays a role on how a bone responds to load. It determines stiffness, elasticity, toughness, and ultimate strength. Here's a breakdown of what those four terms mean:

  • Stiffness is a bone's ability to resist deformation, preventing strain
  • Elasticity is a bone's ability to absorb stress, which allows for strain without damage
  • Toughness is a bone's ability to absorb energy
  • Ultimate strength is how much stress and strain a bone can withstand before it breaks

Like most systems in our body, these properties of bone work together to maximize ultimate strength. If a bone has too much elasticity and not enough stiffness, it will suffer damage too easily, leading to fracture. But conversely, if a bone has too much stiffness and not enough elasticity it will become brittle and unable to absorb any shock, also leading to fracture.

One of the primary failures of osteoporosis drugs is that they ignore this fact. Bisphosphonates make bones stiffer, while ignoring the other qualities that increase ultimate strength. Overly stiff bones grow brittle and more prone to fracture.

Synopsis

Bone is composed of organic and inorganic compounds. Mineralization describes the inorganic mineral part of bone, and as this increases a bone's stiffness increases. Porosity describes the porosity of bone– the spaces between mineral bone containing organic material. The proper balance of mineralization and porosity creates both stiffness and elasticity to increase the ultimate strength of bone. Bisphosphonates increase stiffness at the expense of elasticity. Overly stiff bones become brittle and more prone to fracture.

Cortical And Trabecular Bone

There are two different kinds of bone tissue that serve different functions in a bone. Cortical bone, also known as compact bone, has higher mineralization and density. Trabecular bone, sometimes called spongy or cancellous bone, has high porosity and thus is less dense.

Here are some facts about cortical and trabecular bone:2

  • Cortical bone, due to its high mineralization, is stronger than trabecular bone
  • Cortical bone makes up the outer layer of bones, giving them their structural strength
  • About 80% of bone mass is cortical
  • Only 20% of trabecular bone is composed of bone, the rest is marrow and fat
  • Trabecular bone hosts metabolic activities like the production of red blood cells and bone remodeling processes
  • Vertebrae are largely trabecular bone, having only a thin cortical shell
  • The hip is largely a site of cortical bone
  • The femur's strength comes from its combination of cortical and trabecular bone

Within that stiff outer layer of compact cortical bone tissue, spongy trabecular bone tissue harbors bone marrow and a variety of metabolic activities like the production of red blood cells and bone remodeling processes.

Bone degeneration caused by aging inactivity, or certain health conditions, leads to an increase in porosity of both trabecular and cortical bone. This change in the microarchitecture of bone drastically reduces stiffness, compromising mechanical integrity. This deterioration accounts for about 90% to 75% of the loss of bone strength commonly experienced during aging.1

Synopsis

Cortical bone is the compact bone tissue that makes up the outer layer of bones. It has high mineralization and density. Trabecular bone tissue is on the interior of bones. It is more porous and holds marrow and metabolic processes. Degeneration of bone microarchitecture increases the porosity of both cortical and trabecular bone, reducing mechanical integrity.

About Mineralization

Mineralization is the development of mineral content within bone. It happens in two phases, a primary and secondary biomineral phase.

Newly deposited bone begins to mineralize within about five to ten days, creating about 60% of its total mineral content. Secondary mineralization takes place over approximately 30 months, during which time, calcification completes. The extent to which new bone has completed this maturation process impacts the structural flexibility and stiffness of bone.

The degree of mineralization isn't the only factor influencing the mechanical behavior of bone. The quality of the mineral crystals within the bone matrix also plays a role. That measure is called crystallinity.

Increases in crystal size, number, and distribution change the properties of bone. A certain level of crystallinity is essential for bone strength, but just like with mineralization, if crystallinity is too high bone becomes excessively stiff and brittle.

Bisphosphonates have been found to cause the growth of abnormal, oversized crystals which contribute to bone brittleness. That's another way that osteoporosis drugs increase fracture risk.3

Synopsis

Mineralization occurs in two phases, a fast primary phase, and a much longer secondary phase. As this process takes place, the mechanical properties of bone change. Crystallinity describes the size, number, and distribution of the mineral crystals in bone. If crystallinity is too high bone becomes excessively stiff and brittle. Bisphosphonates have been found to cause high crystallinity.

Bone Mineral Density Doesn't Equate To Bone Strength

It is refreshing to see a medical journal publish a review article that so clearly articulates the failure of the Medical Establishment to devise and use accurate means of assessing bone quality and strength.

Read what the study authors have to say about the inadequate and misleading industry standard for assessing bone strength, bone mineral density:

“…all measures of bone mineral density inherently neglect structural properties of bone (architecture, morphology, geometry), which substantially influences mechanical behavior, and greatly contributes to bone strength and fatigue resistance. Although bone density provides valuable modifiable and measurable insights into bone quality; it is only one of several determinants of bone strength, and should therefore form part of a wider investigative framework which includes structural quantities.”

“Increases in bone mass are not the only way for bones to increase their stiffness and strength. Specifically, bone modifies its structure by adjusting its size (thickness and diameter), shape (contour and dimensions), and architecture (alignment and distribution) to increase cross-sectional area (CSA) and cross-sectional moment of inertia (CSMI) as mechanisms to improve load tolerability and fatigue resistance.”1

As the second half of that quotation states, when bone adapts to mechanical load, it can build strength in ways other than just increasing mineral density. These other qualities also determine bone strength. As described in Part 1 of this series, bone can sense strain. When it meets certain parameters, that strain results in adaptation and growth.

This has been the message of the Save Institute from the very beginning; that bone density is not the only way to assess bone health. Big Pharma and the Medical Establishment ignore the other parameters of bone strength to push osteoporosis drugs on unsuspecting patients.

Synopsis

Bone mineral density is not the only measure of bone strength. By only assessing BMD, the Medical Establishment is ignoring the other qualities that comprise bone strength. Fortunately, we know that mechanical load can apply strain to bone that triggers growth. That growth, even when it doesn't impact BMD, can improve the ultimate strength of bone.

The Role Of Muscle In Bone Strength

Muscle plays an active role in bone strength. Furthermore, bone growth and muscle growth are closely linked. Consider this data on the relationship between bone growth and muscle growth:

“Specifically, when immobilized; muscle cross-sectional area, volume, and strength significantly reduces after ~5 to 7 days; whereas bone thickness, volume and strength significantly reduce after ~14 to 21 days. Conversely, when mechanically loaded; muscle cross-sectional area, length, and strength significantly increase after ~20 days; whereas bone diameter, thickness and volume significantly increases after ~40 to 80 days.”1

We can see how the loss of muscle mass is shortly followed by the loss of bone size and strength. Conversely, this data shows that gains in muscle lead to an increase in bone mass.

This relationship is largely explainable by the mechanical relationship between muscle and bone. Our muscles apply the stress and strain to bones that trigger growth. This relationship is described by Wolff's Law of Bone Formation. So as muscles become larger and stronger, they apply more stress and strain. If muscles shrink, they cease to provide enough strain for bones to maintain their mass.

Muscle and bone also communicate with each other via endocrine-paracrine compounds called myokines. Myokines are small proteins produced by muscle cells in response to muscle contraction. This means that muscle and bone interact and communicate in ways beyond their mechanical relationship. Their interconnectedness highlights the importance of considering the strength of muscle and bone together.

Synopsis

Data tracking muscle mass and bone mass have shown that muscle loss leads to bone loss, and that muscle growth leads to bone growth. That's because per Wolff’s Law, muscle is responsible for the strain that bones require to maintain or gain mass. Muscle and bone also communicate via compounds called myokines.

What This Means To You

This deep analysis reveals how complex and multi-faceted bone strength is. That complexity stands in stark contrast to how Big Pharma and the Medical Establishment perceive and communicate about bone health. Their narrow focus on bone mineral density and prescription drugs blatantly ignores the mechanics of bone composition and behavior.

In stark contrast, the Osteoporosis Reversal Program applies an integrative approach to bone health. And it uses the interconnectedness of our bodily systems (such as the link between muscle and bone) to recommend actions that improve bone health.

Every new understanding and every healthy choice is another step on your journey to stronger bones and healthier living.

References

1 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5601257/pdf/JMNI-17-114.pdf

2 https://www.karger.com/Article/FullText/489672

3 http://pubs.acs.org/doi/full/10.1021/acs.nanolett.7b02888

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15 comments. Leave Yours Now →
  1. Jenny Walsh

    Just found your bone saviour and am intrigued to find a connection to kidney and liver function. I have kidney failure and liver problems plus gout and arthritis would this help me as I also have atrial fibrillation . Writing this down seems as though I am in dire straits but I have some pain but am on Panadol osteo which helps a lot. I am 78 . As you say the body is an amazing Thing I would like your advice as I have just had an injection for Osteoporosis. Thankyou for your article all the best. Jenny Walsh.

  2. Fiona

    Thank you for your great work that enlightens
    us all. I’ll always be in your debt.

    • Vivian Goldschmidt, MA

      It’s my pleasure, Fiona!

  3. Melinda

    Thank you so very much for all of your information that you share. I was diagnosed osteoporosis years ago. After being given several drugs to strengthen my bones , which didn’t help, I found your book. It has helped me in so many ways. I am 68 and no longer classified as having osteoporosis. So many women need to be educated on the truth about osteoporosis. I appreciate what you do to help us.

    • Vivian Goldschmidt, MA

      I congratulate you on your bone health success and thank you for sharing your story, Melinda! Keep up the good work and enjoy your worry-free life 🙂

  4. Alan T Mckinnon

    Thank You!
    For all the help and hope you have given me.
    In2015 I was was diagnosed with renal cancer. Part of my kidney was removed. In 2019 a tumor was discovered in me and I went through another surgery and diagnosed with carcinoid cancer. Then diagnosed with osteoporosis. In June of last year my oncologist gave me an infusion of Zometa. Then my endocrinologist gave me an infusion of reclast because she didn’t check with my oncologist for the greed of money. I didn’t know anything about this drug’s at that time. I do now and what it can do. Now5 to6 month’s later I am able to walk on my own. With7 very little help from my cancer doctors nurses which I seem to know more than them now and no help from endocrinologist at all. She denied that caused pain worst than ether surgery I had. It has been living hell. I did go to an OD to make sure my femur bone was not broke. Thank God it was not. My muscles were completely destroyed it felt like. Exercise is limited for now but I’m A true fighter. With God’s help, that being YOU GOD SENT!, and a drastic change in diet as much as I can and painfully stretching and working up to exercise walking every day I am getting better.
    From every part of me ❤
    Thank you Vivian
    You are truly a very special person
    And God sent
    THANK YOU!
    ALAN

    • Vivian Goldschmidt, MA

      You’re very welcome, Alan! I’m sorry that you’ve been dealing with these health issues and I thank you for your kind words. You should be proud of yourself for your great attitude and perseverance. As you wrote, you’re a “true fighter” and I wish you a full recovery and a bright future. Let us know of your progress 🙂

  5. Pepper

    My tests show bone loss from previous tests. I’ve been on your program for years. Got off meds but MD wants me back on. The article confirms NO injection. But why am I not improving? Two yrs ago fractured my femur while playing tennis. I’ve been active but afraid of falling again.

  6. Sue Beer

    Part 1 and Part 2 were so informative. Never knew all that went into bone formation. I knew about the clearing out of old bone and the rebuilding. That’s about all. Thank you. I look forward to your articles.

    • Vivian Goldschmidt, MA

      Our physiology is amazing! I’m glad you’ve enjoyed this article, Sue!

  7. Lillie O

    WE are given lunch/dinner like bounty meals 3 days a week salty
    kosher meats / which i do not eat also salty soups/she gives me fruit instead of sweet desserts but i still taste salt in cooked veggies she cooks for all but tries to help me but kosher meals are not for me ordering out is impossible

    my disability limits my cooking much for self i try to prepare healthy meals
    vitamins, psy therapy veggies with veggies with eggs in am

    started drinking soy milk — hope it helps— will talk to MD about low dose harmone therapy patch

    • Vivian Goldschmidt, MA

      Thanks for sharing your story, Lillie! Stay positive and keep watching your diet 🙂

  8. Ita

    Thank you, Ita.

    • Vivian Goldschmidt, MA

      You’re welcome, Ita!

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