5 ms·

"Conventional knee and hip implants have to be replaced after about 10 years due to wear and tear." this is really amazing to me! you put metallic, designed-to

"Conventional knee and hip implants have to be replaced after about 10 years due to wear and tear." this is really amazing to me! you put metallic, designed-to-last object inside an organic blend of tissue and bone and human activity and in 10 years its worn out. So much opportunity in the area! Along the same lines, interesting how delicate our bodies are in the short term but rather durable in the long term.

Aelinsaar 10y ago
Your own body basically goes through a skeleton every 7 years, although it's a gradual procedure of course. Your bones are constantly being eaten away, and replaced as part of their maintenance. It's truly amazing, but the secret is definitely, "We can rebuild it" not "Unbreakable".
- andyidsinga 10y ago
  Yes! .. i love thinking about things that way! Speaking about that mentality > the right to repair : https://news.ycombinator.com/item?id=12088631 https://news.ycombinator.com/item?id=12088631 ...raises the question about who can service and repair medical implants. I imagine pace makers would be an interesting case study.
  - tunap 10y ago
    I imagine any inorganic implamt is going to degrade, and have proprietery patents included. Your last question reminded me of the Jarvik Heart, in particular. Interesting read on evolution of the permanent to impermanent artificial heart: http://mobile.nytimes.com/2016/03/21/us/artificial-hearts-ticking-along-decades-after-jarvik-7-debate.html?referer= http://mobile.nytimes.com/2016/03/21/us/artificial-hearts-ti...
    - andyidsinga 10y ago
      that is a great read, thanks!
  - Aelinsaar 10y ago
    It really only avoids being an issue now because of the nature of surgery, the longevity of typical patients vs. implants, and so on. Hopefully, eventually, both of those factors will change and the law is going to be shown to be woefully behind.
- ohyes 10y ago
  So much for wolverine's longevity.
  - stephengillie 10y ago
    Would it be possible to coat a human bone with this new alloy?
    - jm547ster 10y ago
      Are you planning on becoming Wolverine?
      - stephengillie 10y ago
        No, I'm too tall.
        uep 10y ago
        Don't give up so easily. According to Marvel[1], Wolverine is only 5'3, but Hugh Jackman played him at 6'2. For me, the most surprising stat from that page is that he weighs 195 lbs without the metal skeleton, and 300lbs with. He must be insanely stocky for that height. 1. http://marvel.com/characters/66/wolverine http://marvel.com/characters/66/wolverine
        twic 10y ago
        He has at least 80 lbs of sideburns.
        Aelinsaar 10y ago
        Fun fact: Australians are naturally taller, as a result of being suspended upside-down on the bottom of the planet! unreliable narrator
      - oblio 10y ago
        I think that the defining characteristic for Wolverine is the regeneration rate, not the metallic skeleton (which has as a prerequisite the regeneration rate).
- bsenftner 10y ago
  Hopefully, somewhere, there's research to use the body's own maintenance and repair to maintain an artificial limb. That'd be the ideal.
  - Aelinsaar 10y ago
    Regenerative medicine is the goal, and hopefully the future, but it's not easy to get right without accidentally setting off cancers or immune responses you didn't expect or want.
- dghughes 10y ago
  I thought that's why coral was used for bone implants it's first shaped like the part needed then once implanted your own bone cells gradually take over. Maybe it was just a trial I saw to see if it worked or maybe it can only be used for small patches not entire sections of bone like a femur or hip joint.
  - Aelinsaar 10y ago
    No, you're absolutely right. Coral is porous, and pretty biocompatible. It's the same thing that happens with a graft from a cadaver!
    - andyidsinga 10y ago
      makes me wonder about 3d printing with powder-compound coral or cadaver bone - potentially even with very simple FDM 3d printers. I was astounded to learn about the composite materials being developed for cheap 3d printers - see http://colorfabb.com/ http://colorfabb.com/ and https://ninjatek.com/products/filaments/ninjaflex/ https://ninjatek.com/products/filaments/ninjaflex/
      - Aelinsaar 10y ago
        TIL something really cool, thanks.
- aluhut 10y ago
  We should adjust our justice systems to this cycle. You can sit in jail for max 7years. After that you are considered a different person. The justice apparatus needs to use that 7 years to form this new person in a way that it can behave according to the outside system.
  - hugh4 10y ago
    That makes no sense whatsoever. Yes, I know I'm banned. Hello, people with showdead on!
  - andyidsinga 10y ago
    There's something to what you're saying here! - the justice system, and the people involved with it need a real change in mindset. It isn't that you might be a different physical person after 7 years, but a different person based on the current context! There was a great invisibilia podcast on the subject : http://www.npr.org/programs/invisibilia/482836315/the-personality-myth?showDate=2016-06-24 http://www.npr.org/programs/invisibilia/482836315/the-person... See also (referenced in podcast) : http://www.columbia.edu/cu/psychology/indiv_pages/mischel/Walter_Mischel.html http://www.columbia.edu/cu/psychology/indiv_pages/mischel/Wa...
ridgeguy 10y ago
While lots of hip and knee prosthetics last longer than 10 years, too many don't. The implants use synthetic materials to replace both sides of the joint, so there isn't for example, a metal femoral ball running against the patient's original hip socket in a hip prosthetic. It's metal/metal or metal/plastic. I've done a little work in prosthetic materials. It's amazingly complicated. There are metals, plastics, and ceramics as basic options. There is every combination of one of those running against the other in hip implants. There's at least a half-dozen variants within each of the three materials classes. Typical materials are CoCr (metal), Al2O3 or ZrO2 (ceramics) and radiation cross-linked ultra high molecular weight polyethylene (UHMWPE plastic). Prosthetic lifetime gets more and more important as the population of recipients gets younger. They're more athletic, put more load on their implants and they're going to use them longer than the earlier, older recipient population. Yes, serious opportunity here. I hope implants are a once in a lifetime procedure if I ever need them.

Aelinsaar 10y ago

Your own body basically goes through a skeleton every 7 years, although it's a gradual procedure of course. Your bones are constantly being eaten away, and replaced as part of their maintenance. It's truly amazing, but the secret is definitely, "We can rebuild it" not "Unbreakable".

andyidsinga 10y ago
Yes! .. i love thinking about things that way! Speaking about that mentality > the right to repair : https://news.ycombinator.com/item?id=12088631 https://news.ycombinator.com/item?id=12088631 ...raises the question about who can service and repair medical implants. I imagine pace makers would be an interesting case study.
- tunap 10y ago
  I imagine any inorganic implamt is going to degrade, and have proprietery patents included. Your last question reminded me of the Jarvik Heart, in particular. Interesting read on evolution of the permanent to impermanent artificial heart: http://mobile.nytimes.com/2016/03/21/us/artificial-hearts-ticking-along-decades-after-jarvik-7-debate.html?referer= http://mobile.nytimes.com/2016/03/21/us/artificial-hearts-ti...
  - andyidsinga 10y ago
    that is a great read, thanks!
- Aelinsaar 10y ago
  It really only avoids being an issue now because of the nature of surgery, the longevity of typical patients vs. implants, and so on. Hopefully, eventually, both of those factors will change and the law is going to be shown to be woefully behind.
ohyes 10y ago
So much for wolverine's longevity.
- stephengillie 10y ago
  Would it be possible to coat a human bone with this new alloy?
  - jm547ster 10y ago
    Are you planning on becoming Wolverine?
    - stephengillie 10y ago
      No, I'm too tall.
      - uep 10y ago
        Don't give up so easily. According to Marvel[1], Wolverine is only 5'3, but Hugh Jackman played him at 6'2. For me, the most surprising stat from that page is that he weighs 195 lbs without the metal skeleton, and 300lbs with. He must be insanely stocky for that height. 1. http://marvel.com/characters/66/wolverine http://marvel.com/characters/66/wolverine
        twic 10y ago
        He has at least 80 lbs of sideburns.
        Aelinsaar 10y ago
        Fun fact: Australians are naturally taller, as a result of being suspended upside-down on the bottom of the planet! unreliable narrator
    - oblio 10y ago
      I think that the defining characteristic for Wolverine is the regeneration rate, not the metallic skeleton (which has as a prerequisite the regeneration rate).
bsenftner 10y ago
Hopefully, somewhere, there's research to use the body's own maintenance and repair to maintain an artificial limb. That'd be the ideal.
- Aelinsaar 10y ago
  Regenerative medicine is the goal, and hopefully the future, but it's not easy to get right without accidentally setting off cancers or immune responses you didn't expect or want.
dghughes 10y ago
I thought that's why coral was used for bone implants it's first shaped like the part needed then once implanted your own bone cells gradually take over. Maybe it was just a trial I saw to see if it worked or maybe it can only be used for small patches not entire sections of bone like a femur or hip joint.
- Aelinsaar 10y ago
  No, you're absolutely right. Coral is porous, and pretty biocompatible. It's the same thing that happens with a graft from a cadaver!
  - andyidsinga 10y ago
    makes me wonder about 3d printing with powder-compound coral or cadaver bone - potentially even with very simple FDM 3d printers. I was astounded to learn about the composite materials being developed for cheap 3d printers - see http://colorfabb.com/ http://colorfabb.com/ and https://ninjatek.com/products/filaments/ninjaflex/ https://ninjatek.com/products/filaments/ninjaflex/
    - Aelinsaar 10y ago
      TIL something really cool, thanks.
aluhut 10y ago
We should adjust our justice systems to this cycle. You can sit in jail for max 7years. After that you are considered a different person. The justice apparatus needs to use that 7 years to form this new person in a way that it can behave according to the outside system.
- hugh4 10y ago
  That makes no sense whatsoever. Yes, I know I'm banned. Hello, people with showdead on!
- andyidsinga 10y ago
  There's something to what you're saying here! - the justice system, and the people involved with it need a real change in mindset. It isn't that you might be a different physical person after 7 years, but a different person based on the current context! There was a great invisibilia podcast on the subject : http://www.npr.org/programs/invisibilia/482836315/the-personality-myth?showDate=2016-06-24 http://www.npr.org/programs/invisibilia/482836315/the-person... See also (referenced in podcast) : http://www.columbia.edu/cu/psychology/indiv_pages/mischel/Walter_Mischel.html http://www.columbia.edu/cu/psychology/indiv_pages/mischel/Wa...

ridgeguy 10y ago

While lots of hip and knee prosthetics last longer than 10 years, too many don't. The implants use synthetic materials to replace both sides of the joint, so there isn't for example, a metal femoral ball running against the patient's original hip socket in a hip prosthetic. It's metal/metal or metal/plastic. I've done a little work in prosthetic materials. It's amazingly complicated. There are metals, plastics, and ceramics as basic options. There is every combination of one of those running against the other in hip implants. There's at least a half-dozen variants within each of the three materials classes. Typical materials are CoCr (metal), Al2O3 or ZrO2 (ceramics) and radiation cross-linked ultra high molecular weight polyethylene (UHMWPE plastic). Prosthetic lifetime gets more and more important as the population of recipients gets younger. They're more athletic, put more load on their implants and they're going to use them longer than the earlier, older recipient population. Yes, serious opportunity here. I hope implants are a once in a lifetime procedure if I ever need them.