Are usually caused by a sudden impact to the joint.

Sudden impact to the joints (i.e. backward or forward force) can cause a dislocation which can either be a complete dislocation or a partial dislocation. A joint dislocation can damage adjacent structures usually by nerve and vessel impingement causing parethesias and paralysis. Manual correction of the dislocated joint is often favored.

The answer to your question is  it relieves stress and boredom.  the rest of the answer choices would be long term.