The 26-year-old will not play again this term, and also looks set to miss the start of the 2004/2005 campaign.
A challenge with Toulouse's Ludovic Clement resulted in Landrin sustaining a double fracture to his shin-bone, and he underwent an operation in Lille on Sunday.
It is a major blow to LOSC, who are struggling to avoid relegation from Ligue 1.
