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Engineering

The Biomechanics of a Prosthetic Knee Joint

Quick fact

The most advanced prosthetic knees use microprocessors to adjust hydraulic resistance 50–100 times per second, allowing the knee to automatically adapt to walking speed and terrain, something even the best mechanical knees cannot do.

Why this is interesting

A modern prosthetic knee can let an amputee run, climb stairs, and even dance — but it isn't simply a joint on a stick. How does a piece of metal and plastic replicate the complex, dynamic behavior of your own knee?