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Medicine

Artificial Joints (Joint Replacement Prostheses)

Quick fact

The first modern hip replacement was performed in 1960 by Sir John Charnley, and his design—using a metal femoral head and a polyethylene socket—is still the basis for most hip implants today.

Why this is interesting

Your knee bends over a million times a year—what happens when the cushioning wears out? Artificial joints have helped millions walk again, but how do they actually work?