The subtalar joint contributes to 10% of dorsiflexion of the ankle. There are three articulating facets between the talus and the calcaneus, delineated as the anterior, middle and posterior facets. The sustentaculum tali forms the floor of middle facet, and the anterior facet articulates with the head of the talus, and sits lateral and congruent to the middle facet.
The most abundant element on Earth is oxygen, but the most abundant element in the entire universe is hydrogen. On Earth, oxygen makes up approximately 47 percent of the Earth's mass and is found both in Earth's atmosphere and crust. Continue Reading.
Hydrogen (chemical symbol H), named after the Greek word for water-forming, is the most abundant element in the Universe. In fact more than nine-tenths of all atoms are hydrogen atoms. It is the stuff of stars, of cold empty space and of the Earth. Hydrogen is found everywhere and in most compounds.ydrogen in water. Water is the most common chemical compound on the surface of the Earth, covering over two-thirds of the Earth's surface. People are also about two-thirds water. Water is a compound of hydrogen and oxygen.