They could just be tired.
It could be muscle soreness from being on them all day and from walking on hard surfaces without adequate cushioning.
It could also be a problem with the nerves or circulation.
It means nothing it just means that your knees are tired or are aching!
Of course. You can feel weakness in any body part. When you get excited or anxious, you often feel wobbly, especially in your legs and knees, as if they are about to collapse.
No. Actually, the elephant is the only animal with four knees.
legs'
They have 2 knees, each with one patella. So they have 2 patellas, not four. These are located on their hind legs. Their front legs have elbows, not knees.
They're not really called knees, but yes, they are on the front legs, they bend like our knees, and the back legs bend like our elbows. :) hope i helped
It's not an idiom - it's a description of what happens when you get nervous and excited. Your legs feel wobbly and you might even fall over because your knees get weak and collapse underneath you.
African American's knees are black to match the skin on their thighs and lower legs much like the knees of European American's, having white knees that also match the skin of their legs.
Because your legs will hurt and you'll feel tired
Penguins appear to have very short legs and no knees because only the lower leg is externally visible. Their knees and upper legs are feather covered.
I've only found one so far and its the hypural joint which can be found between the caudal fin of the fish and the last of its vertebrae.
The knee joint.