Mandanda cracked a vertebra in his neck while playing for Marseille against Guingamp on Saturday and was immediately stretchered off the field, before being sent to hospital.
Guingamp's Mustapha Yatabare collided with Mandanda in the 19th minute, with the striker's knee connecting with the neck and head of the 29-year-old goalkeeper, who had rushed off his line to smother a pass over Marseille's defence.
Marseille club doctor Christophe Baudot spoke to reporters after checking on Mandanda at La Timone Hospital and claimed the goalkeeper had avoided serious neurological damage.
"Steve has a stable crack of the first cervical vertebra. He went home with a neck brace and there will be further consultation on Monday at La Timone Hospital," Baudot said.
"He will find out about his participation in the World Cup once he sees a spinal specialist.
"There is no neurological disorder, do not worry about his health but there is a concern about the mobility of the spine to carry out his (goalkeeping) activities."
Mandanda, who was born in the Democratic Republic of Congo, was named in France's provisional 30-man squad for the World Cup in Brazil as one of three goalkeepers.
While Tottenham's Hugo Lloris will be first choice for France coach Didier Deschamps, Mandanda notched eight clean sheets for Marseille this season, with the south coast club finishing fifth in terms of defence in Ligue 1 and was expected to be the second-choice goalkeeper ahead of Bastia's Mickael Landreau.
But Mandanda may now miss out on the World Cup finals altogether, which would open the door for Saint-Etienne goalkeeper Stephane Ruffier to be called up from Deschamps' reserve list.
