Combined innovation
Like a lot of our modern technology..
Hip replacement combines multiple innovations.
Patient on their side
On the operating table
Sterile operating theatre
Carefully controlled airflow
Anaesthetised, waist down.
Leg twisted inward
Foot pointing up
Hip dislocated
Head removed
Bone reamed
Bone rasped.
The cup and stem are implanted separately..
Guided, pushed and pressurised into the cement.
Millimetre positioning.
Trial to get the balance and function just right.
And the hip is reduced and closed up layer by layer..
For over two decades, the Charnley Low Friction Arthroplasty, and similar designs, were the most used systems in the world.
However, Charnley himself shared a word of caution.
Particularly about using hip replacement in young patients:
"In this age group we look for factors which offer a ‘built-in restraint’ which will continue after the operation..
"..such as defective knees or ankles, and impose some general physical limitations on the patient”.
A remarkable insight from one of the pioneers.
For me, it's a word of caution about pushing the technology too far.
Younger, more active patients showed higher rates of wear.
A difficult group of people to treat..
Perhaps many millions more cycles
With MUCH more load.
More load that asks more of the hip replacement: both the design and the materials.
Improving upon the Charnley design motivated subsequent changes.
Design changes that I’ll come back to..
For now..
My key take aways from this Hip History series..
Hip replacement is a story of remarkable human innovation
Combining several innovative materials into one design.
The Charnley hip setting the blueprint for hip replacement
Always with Charnley’s words of caution always at the back of my mind.
[HIP HISTORY ENDS]
For now..