England goalkeeper Fraser Forster does not know if he will still be at Celtic when they next play in Europe.
Norwich captain Sebastien Bassong has signed a new two-and-a-half-year contract.
De Bruyne was training with his Belgium team-mates ahead of Friday's World Cup qualifier against Croatia when the incident occurred.
And Belgium boss Marc Wilmots must now wait to discover the extent of any damage 24 hours after losing centre-half Vincent Kompany for his side's final two qualifiers.
Wilmots' side go into the games with a five-point lead in Group A, and a draw in Zagreb will guarantee a place in Brazil next summer.
De Bruyne started two of Chelsea's first three games this season but was left out of the squad for Sunday's trip to Norwich amid criticism from Jose Mourinho.