YOUR KNOBBY KNEES

Can you remember getting out of bed this morning?

Do you realize you used an intricate heavy-duty engineering marvel?

Here’s some clues: most people own 2 of them, they have totally sealed bearings, and come with a lifetime guarantee of sorts; concrete pumping trucks and back-hoes use a similar principle.

So what was that intricate heavy-duty engineering marvel you used to get out of bed?

Lego shows how the cruciate ligaments cross
(side-on view)

Your knobby knees!

If you’re into football or athletics you would have heard of the anterior cruciate ligament (ACL), one of four ligaments that hold together the largest joint in the human body. 

Thanks to ‘irreducible complexity’, if any one of these ligaments is missing the knee will not function properly. The whole structure has to be in place to work: the ligaments, the patella (knee cap), patella tendon, quadriceps tendon, bursae, menisci, cartilage and of course the leg bones that are connected: the femur and the tibia. 

How could the knee possibly be functional while gradually evolving over time?

ACKNOWLEDGEMENTS:

Dr. Bertram Zarins, Mass General Hospital Sports Medicine, Boston, MA

Central Oregon Community College, Dr. Mark Eberle, Professor of Biological Sciences

Wikipedia

Image Credit:                innovationsgames.com