Obviously there is a reason. Consult a medical practitioner.
It is sudden combustion caused without any apparent reason
Because people want jerks to people for no reason because they are mean,rude and have no lives!
due to lack of oxygen
the reason an engine "jerks" is because all of the fuel going into the cylinders are is not completely burning thus causing a loss of power...
Sudden cardiac death is usually caused by ventricular fibrillation (the lower chamber of the heart quivers instead of pumping in an organized rhythm).
A wave caused by a sudden shift in the ocean floor is called a tsunami.
A fall is a sudden movement caused primarily by gravity.
Yes all forms of opiates in high doses cause uncontrollable jerks. There is no research which contributes this effect to one cause. The jerks tend to be caused by multiple factors such as body jerking to wake itself up from deep sleep and give back focused and blood flow to mussels. Second reason might be dopamine level and free radicals built up as seen in people with turrets. One thing certain the jerks progress and can be permanent even after discontinuation of usage.
Sudden knee pain with no injury
An impulse move in dance is when the dancer "tweaks" his or her body suddenly. These movements look like sudden jerks or twitches.
It prevents the cup from toppling over in case of sudden jerks.
Joseph's sudden disappearance was caused by his abduction by unknown individuals.