However, he is not going to retire. He's got too much riding on remaining a technically active player even if he never puts on his Philadelphia Flyers jersey again until he skates in some kind of old timer's exhibition several years from now.
Pronger suffered a concussion last November and never made it back into the lineup last season. General manager Paul Holmgren announced that Pronger was not going to return (source: ESPN.com) in mid-December because of the health problems he had that were associated with the concussion.
While there was a report of "some improvement" after Pronger visited University of Pittsburgh neurologists (source: Philly.com), it was not the type of improvement that would have put the future Hall of Fame defenseman on a path to returning to the ice.
He seems about as likely to return to action as Marc Savard of the Boston Bruins. Savard suffered a brutal concussion after absorbing a head shot from Pittsburgh's Matt Cooke in 2010. While he made a couple returns after that injury, Savard has not played since early in 2011 and it's unlikely he will ever play again either.
Pronger, 37, is not likely to officially retire.
Pronger signed a seven-year, $34.45 million contract that kicked in when he turned 35. Frank Servalli of the Philadelphia Daily News says the Flyers are on the hook for the full amount.
If Pronger was to retire, the team would have to take a salary-cap hit for the remainder of the salary. However, if he does not retire, the Flyers can put him on the long-term injury list and get cushion from the annual salary hit of $4.91 million.
So, don't expect Pronger to retire.
If the salary-cap rules change regarding injured players changes when the NHL and the NHL Players' Association finally hammer out a Collective Bargaining Agreement, the situation regarding Pronger and Savard could change.
But under the current rules, Pronger is not going to retire any time soon.