"Wilf's had a ball at his feet for a while, training solo with the rehab people and physios. He joined in with the team today in a modified session," Hodgson told a news conference on Thursday.
"It's a remarkable recovery. It will be a case of discussing with him, the doctor and the physios regarding when he's ready to come back. It's a major positive," Hodgson added.
Palace have lost three league games in a row since the draw with Newcastle, a poor run that has further highlighted their dependence on Ivory Coast international Zaha to provide the creative spark and energy to their attack.
"All teams rely upon their decisive players, their MVPs. So when you have a player out for any length of time there's always a risk you'll push for him to come back earlier than he should. That's the balance I've got to get right," Hodgson added.
French defender Mamadou Sakho will train on Friday after shaking off a calf injury that has kept him out since February.
Relegation-threatened Palace are 18th in the table with 27 points while defending champions Chelsea are fifth and have lost four of their last five league games.
(Reporting by Shrivathsa Sridhar in Bengaluru, editing by Pritha Sarkar)
