It has been announced that Marquez crashed while riding on a dirt track.
Dr Xavier Mir, a well-known and respected MotoGP surgeon, carried out the surgery at Barcelona's Quiron Dexeus University hospital.
He explained that a titanium plate had been fitted, but added that Marquez might recover in time for the Spanish Grand Prix, which gets underway on May 3 in Jerez.
"The patient presented a deformity to the little finger of his left hand and a subsequent x-ray showed a fracture of the proximal phalanx, with displacement," Dr Mir told reporters. "Therefore, we decided to treat the injury – as we would in the case of any other patient – by fixing a titanium plate to his finger.
"This will allow us to initiate functional recovery after 24 hours and give him a chance of racing at Jerez."
Other than winning the Circuit of the Americas in Austin earlier this month, Marquez has not enjoyed much success as he came fifth in Qatar and crashed out in Argentina. As a result of this, he sits in fifth place on the MotoGP standings and trails leader Valentino Rossi by 30 points.