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 or Group 1 Family of Elements. The highlighted elements of the periodic table belong to the alkali metal element family. Photo Credit: Todd Helmenstine. The alkali metals are recognized as a group and family of elements. These elements are metals.