The Pittsburgh Penguins’ Sidney Crosby announced on Monday that he would be sidelined indefinitely due to concussion-like symptoms.

According to the Associated Press, Crosby said he noticed a recurrence of the problems that sidelined him for more than 10 months earlier this year.

A concussion, which has affected the careers of other NHL stars including the recent incident of Philadelphia Flyer’s captain Chris Pronger, is the result of a brain injury or head trauma.

Signs and symptoms of a concussion may include:

    * Headache or a feeling of pressure in the head
    * Temporary loss of consciousness
    * Confusion or feeling as if in a fog
    * Amnesia surrounding the traumatic event
    * Dizziness or "seeing stars"
    * Ringing in the ears
    * Nausea or vomiting
    * Slurred speech
    * Fatigue

Some symptoms of concussions may be immediate or delayed in onset by hours or days after injury:

    * Concentration and memory complaints
    * Irritability and other personality changes
    * Sensitivity to light and noise
    * Sleep disturbances
    * Psychological adjustment problems and depression
    * Disorders of taste and smell

Source: Mayo Clinic

Meanwhile, fans have flooded Twitter with comments, most wishing Crosby a speedy recovery.