Previews: Inter counting cost of Maicon loss
He could be out for the season, leaving Jose Mourinho with a quandary for Sunday's game at Udinese and beyond.
"Maicon will play the last game of the championship to celebrate the scudetto," coach Mourinho told Italian television.
His side have a seven-point lead with nine games left but must visit second-placed Juventus on April 18, when Maicon would have come in very useful.
His towering frame and powerful runs have made the Brazilian stand out this term as possibly the world's best right back.
Zlatan Ibrahimovic may well have grabbed the headlines for his 19 league goals but Maicon has created many of the Swede's chances while also keeping out the opposition at the other end.
Teenaged left back Davide Santon, brought up from the youth ranks by Mourinho to great effect, may get his chance in his more natural position on the right unless midfielder Javier Zanetti drops back.
Inter's troubles pale in comparison with those of Udinese, who were leaders early on but are now bogged down in mid-table.
Antonio Di Natale is possibly out for the rest of the season after damaging knee ligaments in Italy's 2-0 win in Montenegro on Saturday while fellow Udinese forward Alexis Sanchez is suspended for Sunday along with defender Maurizio Domizzi.
Argentina's Diego Milito was also injured on international duty and will miss Genoa's clash at bottom side Reggina.
Fiorentina, hoping to snatch the fourth Champions League spot off Genoa, will probably be without striker Adrian Mutu for the trip to Atalanta after he hurt his knee with Romania.
The Atalanta game, along with third-placed AC Milan at home to relegation-threatened Lecce, had already been put back to Sunday from Saturday to give Brazil players extra time to jet back from their midweek World Cup qualifying win over Peru.
Juventus, who host improving Chievo on Sunday, will be glad their international players appear to have come through the week unscathed.