punctured lung usually leads to a rib injury so it looks like he might be out for a while
True that... in order to puncture ones lung, something in the ribcage normally has to go snap first.
FWIW if it's punctured he could be back in as little as 1-2weeks, as you can't really do much to repair the puncture but let it heal itself (unless it's a huge tear, but then he wouldn't have walked off the field). Biggest problem is the collateral damage. If he's snapped/broken/cracked ribs he could be months out, if not season (depends highly on the damage).
Perhaps the biggest problem though is the mental issue this could create. Big bloke ends up like that from a smaller bloke. Just as Hickey is starting to hit hard and put his body on the line he suffers an injury. I'd like to think he'd shrug it off, but chances are he'll be hesitant to go for big hits in future (hope I'm wrong there).