The cement sets hard (at ~10mins) with..
A highly irregular side that fits the bone perfectly, and
A perfectly smooth side that fits the implants perfectly.
Bone cement distributes load evenly
And cement likes to be loaded..
Cemented implants rarely loosen.
Brilliant!
A Human compatible grout that can be ..
Sterilised
Made in theatre
Inserted into bone
Pushed into voids + holes of various sizes and textures
..to hold stems and cups (made of very different materials), and
Get pounded by the human body over one million times a year.
And bone cement predictably sets within 10 minutes in the operating theatre,
While the patient is lying there anaesthetised.
PMMA bone cement is another remarkable innovation.
The Complete Hip Replacement
The cemented hip replacement combines several innovations into one design.
A number of new + innovative materials combine into one design.
One design that works when loaded millions and millions of times..
In a salty, unpredictable human body.
The Charnely hip set the blueprint of
A standardised stainless steel stem
A polyethylene cup fixed with
PMMA ‘Perspex’ bone cement.
All materials ‘discovered’, developed and refined over the 1st half of the 20th century.
As if ready to be combined together in the 2nd half of the 20th century.
Hip replacement happened as soon as it could
As soon as the progress that came before could let it happen..
Hats off to those early pioneers 👏👏