Wasps lock Joe Launchbury will undergo neck surgery and will miss England's 2015 Six Nations campaign.
Launchbury, a regular in Stuart Lancaster's second row, missed the autumn internationals with a bulging disc and was initially expected to miss six to eight weeks.
But following further consultation with specialists, Wasps has confirmed the 23-year-old will undergo surgery on Friday 19 December and will face a three-to-four month spell on the sidelines.
"As you would expect, this is a frustrating time for Joe, but the most important thing in all this isn't rugby, it's Joe's long-term health," Wasps director of rugby Dai Young told the club's official website.
"We have consulted specialists in this field and they have recommended surgery as the best option to get him back to full fitness for the long-term.
"Joe is in good hands, being looked after by one of the world's leading surgeons and he will have the full support of the Wasps and England medical teams during his rehabilitation period."
England begin their Six Nations campaign in Cardiff against Wales on 6 February.