Harbaugh said the team will make an announcement regarding Lattimore's status, though he didn't say when.
Lattimore returned to practice this week for the first time since severely injuring his right knee while playing at South Carolina in 2012. He spent all of last season on the non-football injury list after the 49ers selected him in the fourth round of the 2013 draft.
While Lattimore practiced Wednesday and Thursday, he experienced soreness in his knee and missed practice Friday. The recurrence of the knee pain led Lattimore to question whether to continue his comeback, according to Maiocco.
Lattimore also tore a knee ligament in 2011, ending his sophomore season after seven games.
Considered a first-round-caliber prospect before his knee injury, Lattimore rushed for 2,677 yards and 38 touchdowns in three seasons for the Gamecocks.
Veteran Frank Gore leads the 49ers in rushing this season with 423 yards on 102 carries. Rookie Carlos Hyde, who San Francisco selected in the second round of this year's NFL draft, is second among running backs with 161 yards on 14 carries.
The 49ers lost to the Rams 13-10 on Sunday, dropping their record to 4-4.
- Ben Estes