Often after an acute injury of the knee the quadriceps muscle will not contract, which is called âquad inhibition.â. Inability to straighten the leg. Athletes with acute patellar injuries may find that they cannot flex the knee joint fully or straighten the leg. This may be exacerbated by swelling of the knee.
The alkali metals are a group (column) in the periodic table consisting of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr).
The Periodic table can also be divided into several families of elements each having similar properties. For our purposes we will define the following ten families: Alkali metals. The alkali metals, found in group 1 of the periodic table, are highly reactive metals that do not occur freely in nature. These metals have only one electron in their outer shell. Therefore, they are ready to lose that one electron in ionic bonding with other elements. As with all metals, the alkali metals are malleable, ductile, and are good conductors of heat and electricity. The alkali metals are softer than most other metals.