Eagles coach Adam Simpson revealed after the match that Selwood had been carrying the injury since round three and that is was far more severe than first thought.
Surgery will be a last resort for Selwood as it would rule him out for 10-12 weeks, which would effectively end his season.
The Eagles coach told 6PR on Monday night that the club was still trying to work out if he could play again before taking that option.
"We're still making decisions on Scott," Simpson said.
"He's going to need a clean-up at some stage. We’re just trying to figure out when the best time is. We are quite depleted in some areas in our midfield so we're just still assessing that."
Selwood was one of five players in consideration to take over the Eagles captaincy following the retirement of Darren Glass. Simpson was adamant that Selwood's absence due to injury would not diminish his chances in any way.
Surgery is unavoidable for new recruit Elliot Yeo. The former Brisbane Lion broke his hand early in the second quarter during Saturday's three-point win over Gold Coast and has been ruled out for up-to seven weeks.
Yeo, who will go under the knife later this week, has already had dental surgery this season after losing two teeth during the Eagles loss to Collingwood in round 10.
Sam Butler dislocated his finger in Saturday's win after coming on as the substitute but he could still play this week.
Luke Shuey will return after missing last week. The midfielder was withdrawn from the selected side on game-day having failed a fitness test after rolling his ankle at training last Thursday. His coach confirmed on Monday night that he would be back to face St Kilda.
Dean Cox is also expected to return after being rested against Gold Coast.
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