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).
Alkali metals are in the first column of the periodic table, but do not include Hydrogen. The alkali metal family is composed of Lithium, Sodium, Potassium, Rubidium, Cesium and Francium. An example of an alkali metal is Sodium (Na).