The midfielder was forced from the field after 18 minutes of the Reds’ 5-2 victory in the Champions League semi-final first leg at Anfield after picking up the issue during an attempted challenge.
The extent of the injury means Oxlade-Chamberlain is set to miss the remainder of the campaign for Liverpool, as well as the World Cup finals in Russia with England.
The 24-year-old was assessed by the club’s medical team at Melwood on Wednesday morning and no specific timescale is being placed upon his return to action at this stage.
However, Oxlade-Chamberlain will now begin a rehabilitation programme to enable him to reach full fitness again as soon as possible, returning to action next season.