It is Possible for a Person’s Muscles and Other Connective Soft Tissues to Turn to Bone

Today I found out it is possible for your muscles and other connective soft tissues to turn to bone.

The condition is known as Fibrodysplasia Ossificans Progressiva (FOP) or “Stone Man Syndrome”. It affects an estimated 1 out of every 2 million people beginning when they are children, and to date there is no cure.

The telltale sign of someone with this condition is a small big toe that is abnormally formed, often pointing at an odd angle.  As the baby grows into a child, they typically will start developing very painful nodules around their back, head,  neck, and shoulders, generally triggered when the babies or children fall or otherwise bump into something.

These nodules will eventually turn to bone, but because this condition is so rare, the condition is misdiagnosed about 80% of the time.  Generally most doctor’s first think the nodules are cancerous and biopsies are usually performed, as well as radiation treatment and other surgeries, such as the case with Ashley Kurpiel, who was diagnosed with cancer and had her arm amputated at her shoulder when she was just three years old, even though she really just had FOP.

Besides potential amputations when they weren’t necessary, these surgeries will make the condition itself worse.  FOP flare-ups are triggered by trauma to muscles, even just tripping and falling as kids do all the time, is sufficient to trigger a flare-up that will result in the development of bone on their muscles and connective tissues. In addition to muscle trauma, things like getting the common cold or flu can also cause flare-ups.

Even if the condition is correctly diagnosed, there’s little that can be done to help alleviate the problem as surgery is not an option and there is no cure, as noted.

As the person with FOP ages, slowly their ability to move is taken away from them, “entombing a patient in a skeleton of heterotopic bone”. “Even seemingly minor things like preschool immunizations, injections for dental work, [or] minor bumps and bruises from falling off a bicycle, can cause these children to lock up their jaw, lock up their joints that never move again,” says Dr. Fred Kaplan, known as “Uncle Fred” within the FOP community, one of the few doctors who has dedicated his life to finding a cure for FOP.  As he states, “My lifelong goal since I’ve started working on FOP is not just to modify the symptoms but to change the course of the disease. And eventually stop it.”

In the extreme case, such as Fop sufferer Henry Eastlack, they lose the ability to move at all.  In his final days, shortly before his 40th birthday, Henry’s ability to “move” was limited to moving his lips slightly, eyes, and tongue.  But even before this happens, the condition can become extremely debilitating, even life threatening.  For instance, by the age of 17, Tiffany Linker from North Carolina, had to start wearing an oxygen mask as extra bone developed around her rib cage, constricting her ability to expand her lungs.

Tiffany was the first of now over 500 children and adults (of the known 700+ cases) Dr. Kaplan has treated for FOP.  Tiffany had previously undergone numerous surgeries and chemotherapy for what doctors suspected was a rare form of cancer.  Finally, when no treatment worked, Tiffany’s parents were told she’d be dead within two weeks. But, of course, she didn’t have cancer at all.  She had FOP.

Kaplan’s work with Tiffany and others helped inspire him to dedicate his life to the eradication of this condition.  As he said, “I was watching a metamorphosis before my eyes. I was seeing a normal child turn into a child who was imprisoned in a second skeleton — literally imprisoned in this cage of bone.”

Of her condition, Tiffany stated in an interview in 2006,

A flare-up can happen overnight while you’re sleeping. Like, you’ll be walking around one day, and you’ll go to bed and the next day you won’t be able to move. That’s how fast it works…

(As to how it feels to have FOP) I would say, let me tie your arms to your sides where you can’t move them and then put a neck brace and a back brace where you won’t be able to move and then stay in a wheelchair all the time, and then tell me how you feel.

Sadly, a few years after this interview, Tiffany lost the ability to walk, and on July 30, 2012 passed away at the age of just 23.

Many who suffer from FOP have to eventually make the decision as to whether to stay in a wheel chair at all times as their condition worsens, so that they don’t end up being locked in a straight bodied position.

There is finally some hope for people with FOP.  In 2006, Dr. Kaplan and his colleagues at the University of Pennsylvania School of Medicine discovered the gene that causes FOP, specifically a mutation in the ACVR1/ALK2 gene.   Among other things, this gene helps control the development of bones and muscles, as well as the gradual replacement of certain cartilage with bone as you age.  People with FOP have a mutation in one of the two copies of this gene in each cell (one normal copy, one mutated copy).  This results in the body “repairing” damaged fibrous tissue with bone.  For those interested in the ultra-technical version of the cause, it is as follows:

A mutation in the gene ACVR1 is responsible for the disease. ACVR1 encodes activin receptor type-1, a BMP type-1 receptor. The mutation changes codon 206 from arginine to histidine in the ACVR1 protein. This causes endothelial cells to transform to mesenchymal stem cells and then to bone.

This discovery is not only a big deal for the few who suffer from FOP, but also because research into curing FOP may well end up helping those who suffer from osteoporosis, bone fractures, and other such similar conditions.

While there is still no cure, this discovery has opened the door for possible cures or treatments of FOP, such as one developed very recently by Dr. Josef Kaplan, Dr. Eileen Shore, and Dr. Frederick Kaplan.  They engineered an RNA molecule such that it would “silence” the mutated ACVR1 gene, while leaving properly working one in the cell alone. When the treatment is complete, it would leave the non-mutated gene to work normally, thus stopping the advancement of FOP.  While still a long way from a cure, this method at least provides some hope for FOP patients. Further, clinical trials have very recently begun using the retinoic acid receptor gamma palovarotene to inhibit this type of abnormal bone development. In animal testing, at least, this latter treatment has shown some promise, with human trials now underway.

Now normally I wouldn’t try to solicit donations to something on Today I Found Out, but because the condition effects so few people, very little money is available for researching FOP and finding cures, with a large percentage of the funds available for finding a cure for FOP raised by family members of those with FOP (of which there are only about 700-ish people diagnosed world-wide). Further, there are only about 3 principle doctors + support staff like doctoral students and the like working on finding a cure.

So if you’d like to donate to help find a cure for this truly horrifying and debilitating condition, you can do so here: Donate to the International FOP Association

If you don’t have money to spare for a donation, you can also simply use GoodSearch (powered by Yahoo) when surfing the web and designate the International FOP Association as the charity you want money donated to.  GoodSearch will then donate 50% of the money they earn on your searches to the non-profit International FOP Association.

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Bonus Facts:

  • Fibrodysplasia Ossificans Progressiva literally means “Soft Connective Tissue That Progressively Turns to Bone”.  It was known until the 1970s as Myositis Ossificans Progressiva, which means “Muscle Turns Progressively to Bone”.
  • Besides the pain and difficulties with mobility people with FOP suffer, they also often develop malnourishment problems as it progressively becomes more difficult to eat with their jaws locking up.
  • The earliest known case of FOP is from 1692 in France, documented by Guy Patin who had a patient with FOP.
  • FOP is an inherited condition, though in most cases it results from a simple gene mutation, rather than being from someone who has a family history of the condition.  Only one copy of the mutated gene is needed to result in the disorder popping up.  As such, someone with FOP has a 50% chance of passing it on to their children, if they were able to have them.  Though, of course, people with FOP having children is extremely rare, particularly if the person with FOP is female.
  • One FOP female who’s trying to buck the trend is Rachel Winnard of Great Manchester, England, who was one of those misdiagnosed with cancer and twice subjected to chemotherapy when she didn’t need it, first when she was 18 months old, and once when she was nine.   She wasn’t correctly diagnosed until she was 12. In 2008, she asked her boyfriend, Paul, of just 6 months to marry her, apologizing when she did so for “not being able to get down on one knee.”  They were married and she was able to fulfill her dream of being able to walk down the aisle, rather than having to use a wheel chair.  She’s hoping to have children, despite doctors strongly advising against her doing so as this will most certainly make her condition worse and, as noted, there is a 50% chance her child will have the condition.  Her response was, “There’s a chance my child will have FOP, but I love my life and I don’t see why that should change anything… Obviously, it gets me down some days when I can’t do all the things I want to do – like just being able to wash my own hair, that drives me mad – but I just keep going… I’m really positive about my future with Paul. It’s the way I’ve always been and most of the time I try to forget I’ve even got FOP. I just try to live my life as normally as possible.”  So far the couple’s attempt to have a child has not been successful, resulting in one miscarriage.
  • Fascinatingly, cardiac muscles, diaphragm, tongues, muscles that control the eyes, and smooth muscles don’t turn to bone in people who have FOP.
  • One of the most famous cases of someone with FOP was the case of Harry Eastlack, who died in 1973.  Eastlack donated his body to be used in researching FOP, which has been invaluable to researchers.  You can see Eastlack’s skeleton on display at the Mutter Museum in Philadelphia.  One thing you’ll instantly note on Eastlack’s skeleton upon seeing it is that it has no artificial supporting structures to hold all the bones together, as they are all fused thanks to FOP.  Normally a human skeleton will just collapse into a pile of bones after the connective tissues are removed or degrade over time.  As Dr. Kaplan stated, “The gift that Harry has given to the FOP community is inestimable and his bequest has given additional meaning and depth to medical and scientific research well beyond the confines of his mortal existence. I never knew Harry in life… But I bless his memory every time I visit the museum where his legacy continues to educate and inspire.”
  • The non-profit International FOP Association was founded in 1988 by FOP sufferer Jeannie Peeper with the hope that it would help bring together the FOP sufferers in the world, who without this organization generally would never meet another person with FOP.  Today it has over 500 members across 50 nations and donations through this organization are responsible for about 75% of the research funds going to finding a cure for FOP.
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  • Oh God, that is truly horrifying… I’m constantly impressed by how frightening some gene mutations can be.

    • Daven Hiskey

      @Mushyrulez: That was a hard article to research, that’s for sure. The bonus is that now every time anything goes wrong in life, I can always say, “Well, at least I don’t have FOP.” 🙂

  • I heard about this years ago on 20/20 and then recently ran across it in a book I read. It’s a very scary disease.

  • “It effects and” –> “It affects an”

    (I just had to fix that after sharing it on my blog, FB, and G+!)

  • Well I was just googleing my name last night and clicked the link that brought me here .. I had no idea I was mentioned here until last night .. It is really great the awareness FOP is getting lately .. It’s insane to think I’m 1 of 700 known cases worldwide with FOP .. My life has been an amazing ride and I wouldn’t change it for anything!

    • Daven Hiskey

      @Ashley Kurpiel: Your great outlook and positive attitude is inspiring! Hopefully with researchers having nailed down the cause, a cure or effective treatment is just around the corner for you. 🙂

  • Thanks for this blog, Daven. My daughter is 7 years old and has FOP, and I’m always glad to see more accurate info about FOP out there.

    I chuckled when I read your comment about when things are bad, you can say, “At least I don’t have FOP”. I do that when I encounter some of the other rare diseases out there – “Yeah, FOP sucks, but at least Miranda doesn’t have (insert name of horrifying disease here).” Must be human nature to do that!

    Anyway, good job.

    Karen Munro

  • They do have the gene .. They are so close to nailing down a cure!! The 25 years I’ve been in the FOP family- we have come so far!! 🙂

  • Just to set the record straight, Tiffany lost her ability to walk a few years ago, but before this article was even published, she passed away. So I’m sure she’s up there dancing around. I have FOP, was diagnosed 15 years ago and she was a great friend and i looked up to her. I had great respect for what she went through. She persevered through many hardships.

  • Donate to the International FOP Association

    Link no longer works

  • My back feels like that picture.

  • Fascinating article, thanks for all the info and let us hope the genetic research yields the hoped-for results…

  • I am a 26-year-old girl. I have a disease. You can ask for information about my illness and help me.