The news comes as another blow to Wales coach Mike Ruddock, who will have to plan for the RBS 6 Nations defence without both his British & Irish Lions loose forward and injured lock Brent Cockbain.

Jones aggravated the injury on his return to action for the Ospreys last month and requires surgery to remedy a core instability in the shoulder.

The 24-year-old will go under the knife over the next three weeks and his rehabilitation is expected to take at least six months.

Ospreys manager Derwyn Jones said: This is devastating news for Ryan, the Ospreys and Wales. 

''Ryan made a massive impact last season, with his progress culminating on the Lions tour where many observers commented that he was the stand-out player of the tour. 

''It is vital that this procedure is undertaken in order to protect his long-term career. We have taken the best possible medical guidance and they have advised that Ryan is best served by undergoing this surgery.

Cockbain detached his hamstring in Wales' 11-10 victory over Fiji last Friday and underwent surgery on Sunday that will also keep him out for the season.