Jordan Larmour is set to miss the concluding games of Ireland's Six Nations campaign, as well as the new Autumn Nations Cup.
Second row Ryan Baird will also not meet up with the Ireland squad this Wednesday, instead remaining with Leinster to have an abductor injury assessed.
Larmour suffered a dislocated shoulder in Leinster's away win against Benetton in Treviso on Saturday and is due to undergo surgery this week.
Elsewhere, Max Deegan's injury against Dragons on 2 October has been confirmed as an ACL knee injury, which will keep him out for a minimum of six months.
While Rónan Kelleher, Andrew Porter, and Johnny Sexton will be looked at by the IRFU's medical team, Baird, who was also withdrawn from the game against Benetton, is to be further assessed this week by the Leinster Rugby medical team,
Leinster's next game is against Zebre in the Guinness Pro14 on 23 October.