McBride, 35, was injured in the defeat to Middlesbrough, suffering a dislocated kneecap.
Head physiotherapist Jason Palmer told the club's website: "Brian was reviewed in the United States by the US national team's knee orthopaedic specialist, who Brian has known for many years through his involvement with the national team.
"Investigations confirmed he suffered a complete rupture of his quadricep muscle in the areas where the quadricep inserts into the patella (kneecap bone).
"Consequently he underwent a surgical procedure to repair and reattach the muscle. The surgery went very well and he has returned to complete his rehab with the medical staff here at Fulham.
"His recovery will be a steady process in the early stages and we are hoping for a return some time around Christmas."