Why do people have knee caps but not elbow caps?

Question

I find this kind of intriguing. Something to do with the fact that we walk on our legs, not on our arms, maybe? And what about animals that walk on four legs?

Answer 1

Best Answer - Chosen by Voters

The kneecap is a small bone called patella, and it's a shared characteristic of most mammals, not only humans.

The patella is a sesamoid bone, which means that it does not form from a previous cartilaginous structure like much of our skeleton, but it grows within the tendons that attach muscles to certain joints. Mammals also have sesamoid bones in the palm of the hand, and other areas, and there's great individual variation in these bones.
When present, sesamoid bones reinforce the joints and muscular attachments. In the case of the kneecap or patella, it also protects the knee joint (which bends forward, unlike the elbow joint that doesn't "need" such protection).

Answer 2

LOL. I have absolutely no idea.

Answer 3

The patella (kneecap) is a small, flat round bone that articulates with the femur in FRONT of the knee joint. The underside of the kneecap has articular cartilage on it which allows it to glide smoothly over a femoral groove as the knee is flexed.

The quadiceps muscle (thigh) uses the patella as a fulcrum to increase its power when extending the knee. The patellar tendon connects the quadriceps to the tibia. The patellar tendon goes over the top of the kneecap.

So basically the patella provides leverage for the patellar tendon & acts as a fulcrum for your thigh muscle to properly extend your leg.

If you didn't have kneecaps, you would walk with straight, stiff legs.

The arm is a different structure bending in an opposite direction at the elbow. The biceps & triceps attach at the elbow joint. The biceps flexes your arm towards your body. Triceps extends arm away.

Answer 4

Very simple explanation, EVALUTION!!!