Why Don't We Have Elbowcaps?

Arms and legs are pretty similar, from the amount of bones they have to the way their joints bend, but your legs have one thing your arms don't: kneecaps. Ever wonder why?

Hosted by: Michael Aranda
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Sources:
Sophie Regnault and John R. Hutchinson, personal communication

[thepip]

Why aren't there any green mammals? There are green birds, and green reptiles, why aren't there green mammals? Wouldn't it be useful for blending in with grass, or leaves?

[RealMadrid-qemz]

I like the way this guy presents. He speaks like everything is common knowledge. Thumbs up 👍

[Master_Therion]

The outside of the elbow (where the elbowcap would be if we had them) is called the "wenis." I find that *humerus.*

[micky]

One day soon walking on your hands will go viral, and surgeons will start offering 3D printed bionic elbowcaps.
Remember, I thought of it first.

[Dr_V]

The bio-mechanical elbow equivalent of the patella is the olecranon, the prismatic dorsal protrusion of ulna that you can feel under the skin. Also a note on the sesamoid bones definition: they actually DO articulate to other bones (in case of patella with the femur), what makes them special is that they develop inside a tendon, not between other skeletal segments. The patella is embedded in the quadriceps tendon, the "patellar tendon" is just the distal part of it, not a separate structure.

[sensibleb]

I'm looking for my friends Elbo and Erknee. Could you tell me how to get to Sesamoid Street?

[Surajmn]

We don't have elbow caps because we don't knee them. 🤔

[Deltaangle]

They didnt mention this but the olecranon process (the bone tip of the elbow) shares the same mechanical function of the kneecap. It gives the triceps a mechanical advantage allowing it to move loads much more efficiently.

[Fernahnda]

"You don't need elbowcaps because you don't walk on your hands."

Me, the gymnast: Oh, but I do...

[ryanpalso]

0:23 Did you just assume my locomotion?

[vallauritz]

There's some information wrong or missing, the elbow joint doesn't only move by flexing and extending the arm but it also has pronation and supination given by the radius. We probably wouldn't be able to do that if we had elbow caps.

[JohnSmith-tdhd]

Why does the world seem to get all quiet while we're yawning?

[Evipicc]

bruh, so you're sayin' I can bench more if I have a sesame street bone implanted into my elbow?

[om]

'''Why are there people complaining about "around my anus" jokes '''around my anus?

[Iamseraphinamusic]

I'm in a wheelchair so I could use me some elbowcaps

[Infernoraptor]

so I can blame my inability to do push-ups on a missing bone? good to know?

[edi]

For all those that have no problem licking their elbow: Where do you store your tongue? Do you roll it up???

[MuchoBe]

- Do you even lift?
- Not without elbow caps I don't!

[CJthepixiegnome]

The one thing I love about the QQ series is that it ignites this burning curiosity within me. Not a normal everyday "oh, I also wonder why we don't have elbow caps". It's more of a "Hold the phone, somEONE TELL ME WHY WE DONT HAVE ELBOW CAPS I DIDN T KNOE I NEEDED TO KNOW THIS INFORMATION". I love it.

[connerforbis]

Does anyone else feel super fragile after watching videos like this?