compact bone

Regarding bionic limbs

I’ve been thinking about something recently - I think there’s an unsolved problem in bionics. Prosthetics are heavy, and people are going to want to lift superhuman loads with them. Anything heavy, when attached to the body will eventually wear the torso down unevenly, putting stress on muscles and bones that wouldn’t be there normally.

A potential solution is reinforcing the torso, starting with the skeleton. My first thought was to infuse titanium with bone, since it osseointegrates so well. 

It would also be necessary to look into alloys to increase the flexibility of the bionic bone, since complete rigidity is incompatible with the biomechanics of the body.

The idea is to take 3d scans of the subject’s axial skeleton, then run an algorithm on the output to generate replacement bones from this alloy that have channels in which to grow natural osseous tissue. This would ensure that the subject still generates blood through hematopoesis. The titanium alloy would basically act as a replacement for compact bone, but allowing the cancellous tissue to remain as it was.

Once the properties of the new biomaterial are known, several simulations would need to be run to test the new load-bearing capacity, adding supportive struts as needed. You could even fill in the voids between ribs with interlocking, reptile-scale like plates to make the torso resistant to stabbing or gunshot wounds. This would be a useful time to write a program that can take a single ‘part’ design and generate child designs that fit different skeletal physiques.

There are unresolved issues here, however. The musculature will need to be able to attach to this new bone, the tendons and the muscles themselves need to be strong enough to handle the increased loads as well. Interface points between bones will need to be handled. The natural body uses cartilage to do this, and if natural cartilage cannot bind to the augmented bone then a replacement would have to be made. Similarly, ligaments must be either made compatible or substituted.

There are many hurdles to be cleared, but I believe that this problem will need to be solved before the full potential of bionics can truly be realized. I’m sure there are hundreds of little problems I haven’t been made aware of. Can you think of any immediate pitfalls?

How would you go about augmenting the torso to support heavier loads?