The 24-year-old was withdrawn with just over 30 minutes remaining in Salvador on Friday as Les Blues took a big step towards the next round of the tournament.
However, Sakho is confident that he will be fit for France's final group game against Ecuador on Wednesday.
"I felt some pain after going in for a tackle, but I'm okay," he told FIFA.com. "I'm going to have a good rest and then tomorrow the medical staff will examine me to see exactly what the situation is."
Sakho has scored two goals in 21 appearances for France.