Slovakia international Michalik, who has not appeared for Leeds this season, will stay at Brunton Park until January 3.
Michalik originally joined Leeds on loan from Bolton in March 2007 before sealing a permanent £500,000 switch in January 2008.
The 27-year-old was first-choice centre-half during the first half of the 2008/9 season, but has failed to hold down a place in the starting line-up at Elland Road since the arrival of skipper Richard Naylor in January 2009.
Michalik was included in Slovakia's initial 29-man World Cup squad, but was omitted from the final 23-man party that competed in South Africa this summer.
Source: PA
Source: PA