Garcon described the injury that's sidelined him for four of Washington's past six games as a "plantar plate tear" near his second toe. The plantar plate is a ligament that holds a toe in its joint.
Garcon said Thursday that "surgery is an option" that probably would end his season, adding: "But we don't really want to think about that at all."
He visited a foot specialist Wednesday.
Garcon only has eight catches for 153 yards this season, his first with the Redskins after signing a $42.5 million, five-year contract as a free agent.
Meanwhile, linebacker London Fletcher is being evaluated for a head injury and has missed practice for a second consecutive day, putting his consecutive-games streak in doubt.
Coach Mike Shanahan says Fletcher has spent about six hours being checked Thursday by a neurologist for a "balance issue." Shanahan listed Fletcher as not practicing because of head and hamstring problems.
Shanahan said he expects to be able to say more about Fletcher's status Friday.
The Redskins (3-4) play at the Pittsburgh Steelers (3-3) on Sunday.
The 37-year-old Fletcher has appeared in 231 consecutive games -- every one his teams played in since he entered the league as an undrafted rookie with the St. Louis Rams in 1998.
Information from The Associated Press was used in this report.